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1. Descrihe the murmurs heard. and specifythe stethoscope location where they are bestheard, if the patient has aortic stenosis. If thepatient has aortic regurgitation.Aortic stenosis is recognized by its characte rist ic systolic murmur. bestheard in the second right intercostal space (over the aortic arch) withtransmission into the neck. Aortic regurgitation is recognized by its diastolicmurmur. best heard along the left sternal border. [Hines. Stoelting'sCo-existing. 5e. 2008 pp37, 39]2. 'Name the organs in the vessel rich group(VRG). What percent of cardiac output goesto each of these organs?The brain, kidney. liver, lungs , heart. diges tive tract. and endocrine tissuesare organs of the vessel rich group (VRG). These are the wel/perfl/sed organs. 25% of the ca rdiac output goes to the liver; 4-5% (225mLim in) to the heart; 15% to the brain; 20% to the kidneys; and 100% tothe lungs. IGuyton. TMP. li e. 2006 pp l96t; Stoelt ing, PPAP. 4e. 2006pp3 1; Morgan, et al.. C/ill. Allesth .. 4e. 2006 pp l5813. In words. descr ibe where isovolumelricrelaxation occurs on the left ventr icularpressure-volume loopIsovolumctric relaxa tion occurs from closure of the aortic valve to openingof the mitral valve on the left vent ricular pressure-volume loop. [Nagel·hout & Zaglan iczny. NA. 3e. 2005 pp43614. ln words. describe where isovolurnetriccontraction occurs on the left ven tricularpressure-volume loop.Isovolumetric co ntraction occurs from closure of the mitral va lve to openiugof the (lortic valve on the left ventricular pressure-volume loop. [Na·gelhout & Zaglaniczny. NA . 3e. 2005 pp43615. -What nerves carry the afferent and efferentsignals of the Bainbridge reflex? Whatdoes the Bainbridge reflex help prevent?When the great veins and right atrium are stretched by increased vascularvolume. stretch receptors send afferent signals to the medulla via thevagus nerve. The medulla then transmits efferent signals via the sympatheticnerves to increase heart rate (by as much as 75%) and myocardial co ntractility. The Bainbridge reflex helps prevent damming up of blood inveins, the atria, and the pulmonary circulat ion.IGuyton. TMP. lI e. 2006pp21216. @)What percentage of cardiac output isdelivered to the highly-perfused organs(heart, lungs, brain, kidneys, and liver)?Approximately 75% of resting cardiac output is delivered to the vesselrichorgans. although they constitute only 10% of total body mass. [Stoelting7. @)Describe myocardial preconditioning.Myocardial preconditioning is a short-term rapid adaptation to briefischemia such that during a subsequent, more severe ischemic insult.myocardial necrosis is delayed. The infarct-delaying properties of ischemicpreconditioning have been observed in all species studied. Five minutesof ischemia is sufficient to initiate preconditioning, and the protectiveperiod lasts for I to 2 hours. [Stoelting. PPAP. 4e. 2006 ppl71; Cote, 8. @)Describe the cellular mechanisms mediatingmyocardial preconditioningPharmacological activation of adenosine receptors (particularly al and a2subtypes) initiates preconditioning via intracellular signal transductionmechanisms involving protein kinase C and adenosine triphosphate (ATP)-dependent potassium channels (KATP). Other factors involvedinclude including the sodium: hydrogen exchanger, inhibitory G proteins,and tyrosine kinase. [Stoelting. PPAP. 4e. 2006 pp171; Cote. PAle. 4'h2009 pp343; Barash. Clin. Alles .. 6'h 2009 pp430]9. @)Whatanestheticagentscan trigger ormodulate the myocardial preconditioningresponse? What anesthetic agent can antagonize the effect?The vo lat ile anesthetics mimic ischemic preconditioning and trigger asimilar cascade of intracellular events resulting in myocardial protectionLIlat las ts beyond the elimination of the anesthetic. Adenosine or opioidagonists delivered into the coronary circulation may also mimic preconditioning.Ketamine antagonizes the protective effect of preconditioningand thus should be used with caution in the patient at risk for myocardialinfarction in the perioperative period. [Stoelting. PPAP. 4e. 2006 pp171;Cote. PAle. 4,h 2009 pp343; Barash. Clin. Anes .. 6'h 2009 pp430]10. What monitoring is indicated for managingthe patient with a history of congestiveheart failure secondary to diastolic dysfunction?The use of invasive monitoring such as central venous pressure (CVP) orpulmonary artery catheter (PAC) may be indicated in managing the patientwith a history of congestive heart failure secondary to diastolic dysfunction.[Miller & Stoelting. Basics. Se. 2007 ppS2611. List 4 compensatory responses in thepatient with cardiac failure.?Four major compensatory mechanisms participating in the response tocardiac failure are (1) increased left ventricular preload, (2) increasedsympathetic tone, (3) activation o/the renin-angiotensin-aldosteronesystem, (4) release of AVP (arginine vasopressin, antidiuretic hormone),and (5) ventricular hypertrophy. These mechanisms initially compensatefor cardiac failure, but with increasing severity of the disease, they mayactually contribute to the cardiac impairment. [Morgan, et al., Clin.Anesth .. 4e. 2006 pp433-434; Hines, Stoelting's Co-existing. Se. 200812. What is the principal hemodynamicalteration with cardiac tamponade? What isBecks triad?The principal hemodynamic feature of cardiac tamponade is a decrease incardiac output due to a reduced stroke volume, secondary to an increasedcentral venous pressure and thus reduced venous return to the heart. Thediagnosis of postoperative cardiac tamponade should be consideredwhenever hemodynamic deterioration is encountered, particularly whenreductions in CO or BP or both are not readily resolved by conventionalmanagement. Becks triad is the constellation of hypotension. jugularvenous distension, and distant, muffled heart sounds. [Morgan, Mikhail,and Murray, Clin. AnesthesioL, 41h ed., 2006, pS26; Yao & Artusio, Yao &Artusio's Anesthesiology: Problem-Oriented Patient Management, Sih ed.,13. What class of drugs may be given preoperativelyto the untreated. asymptomatic.mildly hypertensive patient to attenuatetachycardia with tracheal intubation and tachycardia and emergence?A small oral dose of a beta-adrenergic antagonist, such as labetalol (Normodyne,Trandate), atenolol (Tenormin), or oxprenolol (Trasicor) givenpreoperatively to the asymptomatic, mildly hypertensive patient mayeffectively attenuate tachycardia with tracheal intubation or upon emergence.[Yao & Arlusio, Yao & Artllsio's Allesthesiology: Problem-Oriented14. What muscle ac ts as a barrier to reg urgitationin the conscious subject?In the awake subject, the cricopharyngeus muscle is the primary muscularbarrier to regurgit at ion.INagelhout & Zaglaniczny, NA, 3rd ed., 200415. Laryngospasm is caused by stimulation of which nerve?Stimulation of the superior laryngeal nerves may cause laryngospasm16. Wesl's zones of the lung describe alveolarperfusion based on the relationship of threepressures: alveolar press ure (P,o\.). arterialpress ure (PP .... ) and venous pressure (Ppv).Which region shows the greatest increase inblood flow over the distance of the zone?West zone 2 shows the greatest increase in blood now over the distance ofthe lone; blood now is zero at the nondependent start of zone 2 and increaseswith dependency over the distance of zone 2. Reminder: zone 2 isthe "waterfall zone" of intermitte1lt blood flow. where PPA> P A> PPV. IWest,P"/",. Physiol .. 8e. 2008 pp43-44; Barash, Clinical Anes .. 5e. 2006 pp82 If;17. , IIWest's zones of the lung describe alveolarperfusion based on the relationship of three pressures: alveolar pressure (PA), arterial blood now, and venous pressure (Ppv). Which region has the maximal blood flow of any zone?West zone 3 possesses the maximal pulmonary blood now of any zone(region). Reminder: zone 3 is the "distension zone" with continuouspressures: alveolar pressure (PA), arterial blood now, where PPA> Pllv> P A.18. @)How does marked right-to-Ieft intrapulmonaryshunting manifest on radiographs?Marked right-to-left intrapulmonary shunting (shunt flow> 15%) is associatedwith radiographically discernable findings such as pulmonaryatelectasis, parenchymal inftltrates, or a large pneumothorax. [Morgan19. lWhat happens to pulmonary blood flow in zone 4 of the lung?Lung regions where PI'A>P1SF> Ppv> PA are termed zone 4 regions. Bloodflow in zone 4 is reduced by gravitational compression of the lung parenchymaor by illterstitial edema formatioll. [Stoelting, PPAP. 4e. 2006pp746; Hagberg, Bellllmofs Airway Mallagemellt. 2e. 2007 pp 116-117[20. What is the carbon dioxide content (invol %) in room air? What is the partial pressureof CO2 in room air (assume standard pressure)?The carbon dioxide content of room air is 0.03%. According to Daltonslaw, the part ial pressure 0(C02 in room air is 0.23 mm Hg. [AuthorsJ21. What are pulmonary J-receptors?Juxtapulmonary-capillary receptors U receptors) are located in the walls ofthe pulmonary capillaries or in the interstitium, hence the name. J receptorsappear to be stimulated by pulmonary vascular congestion or an increase in pulmonary interstitial fluid volume. leading to tachypnea. TheJ receptors may also be responsible for the dyspnea encountered duringpulmonary vascular congestion and edema secondary to left ventricularfailure. [Levitzky. Pulm. Physiol .. 7e. 2007 ppI99-200; Lomb & Nun22. lWhich nerve fiber type innervates pulmonary J receptors?C·fibers lie in close relationship to the pulmonary microcirculation andappear to in nervate the pulmonary J receptors. The afferent pathway from.vagalll"ves, [Levilzky. Pulm. Pilysio/.. 7e. 2007 ppI99-200; Lomb &23. KLung auscultation reveals basilar cracklesand chest radiographs exhibit "whited-out"areas; what is your diagnosis?The detection of basilar crackles on auscultation is the traditional hallmarkof early pulmonary edema. A "butterfly" appearance or "whitedoue'areas on chest radiographs support the diagnosis of pulmonary edema24. What airway event may lead to the developmentof negative pressure pulmonaryedema (NPPE)? Describe the mechanism of NPPE formationAcute airway obstruction such as laryngospasm can lead to negativepressurepulmonary edema. As the patient breathes against a closed glottisduring laryngospasm, a more negative (greater magnitude) intrathoracicpressure is created. The increased intrathoracic pressure is transmittedto interstitial tissue, creating a greater hydrostatic pressure gradientbetween the interstitial space and the pulmonary circulation. The increasedhydrostatic pressure gradient from blood to tissue will promotemovement of fluid from the blood to the tissue and into the alveoli. [Stoelting& Miller, Basics, 5th ed., 2007, p470; Nagelhout & Zaglaniczny, NA,25. ~How is negative-pressure pulmonaryedema (NPPE) treated?Negative-pressure pulm~nary edema (NPPE) is treated by positive endexpiratorypressure (PEEP) ventilation. Diuretics and fluid restrictions arenot required as the condition is self-correcting. [Yao & Artusio, Yao &Artusio's Anesthesiology: Problem-Oriented Patient Management, 5th e26. What is the primary mechanism ofhypoxemiain the patient with chronic obstructivepulmonary disease (COPDThe primary mechanism of hypoxemia in obstructive pulmonary diseaseis regional mismatch o/ventilation and perfusion (V/Q mismatch). [Dunn,et al., Clin. Anes. Procedures of the Massachusetts General Hospital, 71h27. @What membrane ion channels playa rolein cell repoiarizationThe necessary actor in causing both depolarization and repolarization ofthe nerve membrane during the action potential is the voltage-gatedsodium channel. A voltage-ga ted potassium channel also plays an importantrole itl increasing the rapidity of repoiarization of the membrane.Repolarization begins with the clos ing of the voltage-ga ted sodium channels,followed by opening of the voltage-gated potassium channels. Duringearly repolarization. the sodium channels are in the closed. inactiveco nformation causing the (eillO be absolutely refractory to stimulus.During the latter stages of repoiarization, the voltage-gated sodium channelshave returned to the closed. res ting conformation. and the cell isrelatively refractory to stimulus. [Guyton, TMP. li e. 2006 pp62; Nagelhout28. v'Which neurotransmitter is the mostcommon exci tatory neurotransmitter in thece ntral nervous system (eNS)?Glutamate is the most common exci tatory neurotransmitter in the centralnervous sys tem (CNS). Glutamate is an excitatory amino ac id neurotransmiller.[Stoelting, PPAP. 4e. 2006 pp674; Miller, Allestilesia. 6e.29. List three (3) common ionotrop ic glutamatereceptors in the central nervous sys tem(eNS). Which electrolytes (ions) passthrough these receptors upon activation?The three ligand-gated ionotropic glutamate receptors of the eNS are: (I)N-mcthyl-D-aspartate = NMDA, (2) AMPA, and (3) kaina te. When theligand glutamate binds to these iono tropic recepto rs, a transmembrane,cation-selective channel opens. pe rmitting influx of Nat and Cah andeffiux of K+. Sodium is the main ion permeating the channel, leading tomembrane depolarization. [Stoelting, PPAP. 4e. 2006 pp674; Guyton30. What enzyme catalyzes the synthesis ofacetylcholine (ACh)? Where does ACh synthesis occur?Synthesis of acetylcholine (ACh) occurs in the cytoplasm of nerve terminals.Choline acetyltransferase (ChAT) catalyzes the formation of AChfrom the precursors (substrates) choline and Acetyl-CoA (from mitochondria).[Stoelting, PPAP. 4e. 2006 pp701; Guyton, TMP. lie. 200631. K'The gamma amino butyric ac id type A(GABA,) recep tor has at least 7 ligand bindingsites. Identify the 7 ligand binding sitesthe GABA ... receptor possesThe 7 ligand binding si tes on the GABA, receptor are for: (1) GABA, (2)barbiturates, (3) benzodiazepines, (4) propofoJ, (5) steroids, (6) anesthetie/alcohol. and (7) picrotoxin. Notice that 5 of th e 7 sites involve anestheticagents!32. vWhat is the conus med ullaris? What is the filum terminale?The conus medullaris is the blunt, tapering tip of the spinal co rd. The piaalone continues from the conus medullaris and after piercing the duralsac, continues wi th a covering of dura to the coccyx, forming the filumterminalis. The fi lum terminalis is comprised of the pia and dura malere.[Ellis & Feldman, Allatomy for Allaestlretists. Be. 2004 pp 120; Authorsl33. N'Desc ribe the anatomy of the hypogastricplexus.The pelvic viscera in men and women-the urogenital organs. the colon.and the rectum-are supplied by afferent fibers from the lumbar sympatheticchain. The superior hypogastric plexus is a retroperitoneal structurethat is fo rmed by confluence of the bilateral lumbar sympathetic chaitls; itis siluated between the bodies of the Ls and S I vertebrae. The pelvic paincaused by either inflammatory diseases or cancer can be relieved by inter·ruption of bilateral sympathetic pathways. which can be achieved with asuperior hypogastric plexus block.34. Where do preganglionic parasympatheticnerves originate?Preganglionic parasympathetic nerves arise from nuclei of cranial nervesIII, VII, IX and X in the brainstem and also from sacral segments 2-4 (S2-S4) of the spinal cord. Owing to these origins, the parasympathetic systemis also known as the craniosacral division.35. @List the six (6) orbital muscles, their runction,and their motor innervationSuperior rectus: Supraduction or orbit ("look up"); innervation by eN III(oculomotor)Inrerior rectus: Inrrad uction or orbit ("Iook down"); innervation by eN III- oculomotorMedial rectus: Adduction or orbit ('look inward'); innervation by eN 111 -oculomotorLateral rectus: Abduction or orbit ('look outward"); innervation by eN VI- abducensSuperior oblique: Intorsion, depression or orbit ("look in and down");innervation by eN IV - trochlearInferior oblique: Extorsion, elevation or orbit ("look out and up"); inner·vat ion by eN III . oculomotor[Nagelhout, NA . 4''- 2009 pp943; AuthorsJ36. IWhich cranial nerve provides sensoryinnervation to the face? List the threebranches of this nerve,The trigeminal nerve (eN V) provides sensory innervation to the face. The trige minalnerve has three branches: the ophthalmic. the maxillary. and the mandibular.The ophthalmic and maxillary are pu rely sensory. whereas the mandibularnerve is a mixed (motor & sensory) nerve.IBarash.37. Describe the motor and sensory functionsof the mandibular branch of the trigeminalnerve (eN V).The anterior branch of the mandibular nerve provides motor innervation to themuscles of masticat ion (chewing, "moves the mandible"). The posterior branch ofthe mandibular nerve provides sensory innervation to the lower teeth and gums("feels the mandible, in side and out"). lila rash, Clin. Anes., Sib ed., 2006. pp72l -722; Morgan, Mikhail, and Murray, Clill. Anesthesia/., 41h ed., 2006, pp37S-376;38. Describe the sensory inn ervation of theracial nerve (eN VII).The racial nerve (eN VII) provides special sensory innervation to theanterior two-thirds of the tongue (taste) and general sensory innervationto the tympanic membrane. external auditory meatus, soft palate, andpart of the pharyn x. IMorgan. Mikhail39. N'ln addition to hyperplastic lymphoidtissue and a large tongue (~ difficult airway),what other finding may be coexistentwith sarcoidosis?Polyneuropathy is a frequent finding in the patient with sarcoidosis.Unilateral or bilateral facial nerve paralysis may occur due to sarcoidinvolvement of the facial nerve as it courses over the parotid gland. DiabetesinSipidus (DI, both neurogenic and nephrogenic forms) may alsooccur with sarcoidosis. [Stoelting & Dierdorf40. vIdentify the anesthetic agents that areabsolutely contraindicated in the patientwith a family history of malignant hyperthermiaAll volatile (potent) inhalational agents and succinylcholine are absolutelycontraindicated in patients with malignant hyperthermia41. What are the clinical mani festations ofmyotoniC dystrophy (Ste inert's disease)?Myotonia dys trophy (Steinert's disease. myotonic atrophica) is a multisystemdisease that usually manifests as facial weakness (expressionlessfacies). wasting and weakn ess of the sternocleidomastoid muscles. ptosis,dysarthria, dys phagia, and inability to relax the hand grip (myotonia).Frontal balding, catarac ts. and testicular atrophy in males form a frequentlyrecog nized triad of characteristics. INage1hout, N42. ?Identify tl~ e genetic pattern of inheritancefor myotonic dystrophy and describe thepathophysiology of this group of degenerative diseasesMyotoniC dystrophy (MD) is inherited as an au tosomal dominant traitand usually manifests in the second or third decade oflife. Myotonicdystrophies are charac terized by persistent contracture (myoton ia) aftervoluntary contracture of skeletal muscle or following electrical stimulation.Electromyographic fir/dings are diagnostic and are characterized byprolonged discharges or repetitive ac tion potentials. Skeletal muscleresting membrane potentials arc also lowered (less polarized) in patientswith MD. The inability of the skeletal muscle to relax after voluntarycontraction or stimulation res ults from abnormal calcium metabolismATP-driven pumps fail to return calcium to the sarcoplasmic reticulum(SR) thus the unsequestcred ca lcium remains available to produced sustainedskeletal muscle contraction. INagelhout, NA. 4''- 2009 pp795-79643. @lWhat four anesthet ic concerns should youhave for the patient with myotoniC dys tro phy?Preoperative evaluation and management of anes thesia in patients withmyotonic dystrophy must consider the likelihood of (I) cardiomyopa thy.(2) respiratory muscle weakness and sensitivity to res pirato ry depressants, (3) vulnerability to asp irat ion of gas tric contents, and (4) potentialfor abnormal responses to anesthetic drugs. INagelhout, NA . 4th. 2009pp796; Hines, Stoelting' Co-existing. 5e. 2008 pp449144. Should succinylcholine be used in theanesthetic management of the patient withmyotonic dystrophy?Succinylcholine should not be used in the patient with myotonic dystrophybecause succinylcholine can produce intense generalized myotoniccontracture that makes ventilation or intubation difficult or impossible.[Nagelhout, NA. 4th. 2009 pp796; Hines, Stoelting's Co-existing. Se. 200845. @)What is the medical management of thepatient with myotonic dystrophy?Treatment of myotonic dystrophy is symptomatic and may include theuse of phenytoin, quinine, and procainamide. These agents delay thereturn of membrane excitation by blocking rapid sodium (Na+) influx intomuscles. Quinine and procainamide should be used with caution as theymay worsen cardiac conduction abnormalities (prolonged P-R interval).[Nagelhout, NA. 4th. 2009 pp796; Hines, Stoelting's Co-existing46. ft'Myasthenia gravis is characterized bywhat symptoms? What is the cause of thesesymptoms?Myasthenia gravis is characterized by weakness and easy fatigability ofskeletal muscles. The weakness can be asymmetric, confined to one groupof muscles, or generalized. Easy fatigability of skeletal muscle in myastheniagravis is caused by autoimmune destruction of nicotinic acetylcholinereceptors at the neuromuscular junction47. ft'Onset of myasthenia gravis (MG) is slowand insidious and any skeletal muscle groupmay be involved. Onset is most common inwhich muscles?The most common onset of myasthenia gravis is ocular. Ptosis and diplopiaresult. If the disease remains localized to the eyes for 2 years, thelikelihood of progression to generalized48. Identify the anesthetic concerns for thepatient with scoliosis due to muscular dystrophy?The patient with scoliosis due to neuromuscular disorders, such as musculardystrophy, is predisposed to malignant hyperthermia, cardiac dysrhythmias,and untoward effects of succ inylcholine (hyperkalemia, myoglobinuria,sustained muscular contraction). [Morgan, et al., Clifl. Anesth..49 K'What organ produces proopiomelanocortin(POMC)? What substancesare derived from proopiomelanocortin(POMC)?Pro-opiomelanocortin (POMC) is a large preprohormone synthesizedprimarily in the anterior pituitary and hypothalamus. Processing of thepreprohormone POMC leads to the formation of a number of smaller,active peptide hormones, namely adrenocorticotropiC hormone (ACTH),melanocyte-stimulating hormone (MSH), beta-endorphin, metenkephalin,and beta-lipotropin. [Guyton & Hall, TMP, Illh ed., 2005,pp955-957; Nagelhout & Zaglaniczny, NA, 3rd50. What is the best initial test of thyroidfunction in ambulatory individuals?What is the best initial test of thyroidfunction in ambulatory individuals?51. Calcitonin is released from what organ? Iscalcitonin a weak or a strong regulator of calcium?Calcitonin is a polypeptide hormone secreted from the parafollicular cells(C cells) of the thyroid gland. Calcitonin has a quantitatively weak role incalcium homeostasis in the adult. [Stoelting, PPAP. 4e. 2006 pp808;52. What is the major physiologic action ofcalcitonin?Calcitonin tends to decrease plasma concentration of calcium ions, due toa decreased activity of os teoclas ts (bone breakdown) and an increasedactivity of osleoblas ts (bone deposition). In general, calcitonin has oppositeeffecls 10 those of para~lyroid hormone (PTli). [Stoelting, PPAP. 4e.2006 pp808; Guyton, TMP. lIe. 2006 pp988-98953. ....In what vessels would you find the highestconcentration of insulin?Insulin is produced in the beta cells of the pancreatic islets (of Lan ger~hans), as you know. Venous blood from the pancreatic islets drains intothe hepatic portal veil!, via the pancreatic vein, and then into the generalcirculation. ]Nagelhout & Zaglaniczny54. @Whichzonaoftheadrenalcortexis theonly one capable of synthesizing aldos terone?Why is this true?Aldosterone is synthes ized in the zona glomerulosa alone because thiszona is the only one to contain aldosterone synthase. IBoron, Med Physioi.2e. 2009 pp106655. @)Which two zonae of the adrenal cortexcan synthesize cortisol and corticosterone?Why?The zona fasciculata and zona reticularis can synthesize the corticosteroids,cortisol and corticosterone, because they contain the necessary enzyme,17-a-hydroxylase for synthesis56. @)How much daily cortisol is normallysecreted from the adrenal glands? Howmuch during stress?The normal adrenal gland can secrete 20 mglday of cortisol and maysecrete up to 200-500 mglday during stress. NB: Both the Barash 2009Handbook and textbook incorrectly state daily cortisol = 200 mg. [Guyton,TMP. 11 e. 2006 pp974t; Morgan, et aI., CUn. Anesth57. @)Perioperativesupplemental steroid coverageregimens are either low-dose (physiologic)or high-dose (supraphysiologic). Describe each regimenLow-dose (physiologic) supplemental steroid coverage: cortisol 25 mg IVbefore induction of anesthesia followed by continuous infusion, 100 mgIV over 24 hr. Supraphysiologic coverage: cortisol 200-300 mg IV individed doses on the day of surgery [Barash, Handbook. 6th? 2009 pp79058. K'What disease is caused by the destructionof the adrenal gland, resulting in a combinedmineralocorticoid and glucocorticoid deficiency?Addison's disease (primary adrenal insufficiency) is caused byautoimmunedestruction of the adrenal cortex, causing both glucocorticoid andmineralocorticoid deficiency. [Morgan, Mikhail, and Murray, Clin. AnesthesioL59. vDroperidol is to be avoided in the patientwith pheochromocytoma, as you know,because of the possibility of hypertensivecrisis from catecholamine release. Describehow droperidol may promote catecholaminerelease from the adrenal medulla. Droperidol (Inapsine) is a potent antidopaminergic (D2 antagonist), withsome histamine and serotonin receptor antagonist activity. The catecholaminerelease promoted by droperidol may be due to antagonism ofpresynpatic dopaminergic receptors that normally inhibit release of catecholamines(a normal negative feedback mechanism). [Stoelting & Dierdorf,Anesthesia and Coexisting60. Can the liver act as a reservoir for blood?What controls the rese rvoir functions of theliver?Yes, Ihe liver is a majo r reservoir for blood, Sloring up 10 500 mL of bloodat any time. The reservoir function of the liver is dependent upon vasculartone and vascular pressures. especially on the venous side. Therefore. theautonomic i'lnervation to the liver will playa crucial role in the reservoirfunction of the liver. Intense sympathetic nervous sys tem stimulationmay result in expulsion of up 10 400-500 mL of blood from Ihe liver in amallcr of seconds. [Barash, Clillical Alles.. 5e. 200661. What percenlage of ca rdiac outpul goes 10Ihe liver? Whal percenlage of hepalic bloodflow is provided by Ihe porlal vein? By the hepatic artery?Tolal hepatic blood flow is aboul 25% of ca rdiac OUlpUt. The hepaticportal vein supplies 70-75% of lola 1 hepalic blood flow; Ihe hepalic arteryprovided Ihe remaining 25-30% of lola 1 hepatic blood flolV.62. ,,",Whal percenlage ofhepalic oxygell mpplyis provided by Ihe portal vein? By Ihe portalartery?The hepatic portal vein provides about 50% of total oxygen to the liver(s ince il is venous blood) and the hepatic artery provides the remaining50% of lola 1 oxygen 10 Ihe liver. Summary: blood flolV is 75:25 (portal vein10 hepalic arlery) bUI oxygen supply is 50:50. [Morgan, el ai., Ciill.63. ,,?'What two vessels converge to form thehepatic portal vein?The hepa tic portal vein is fo rmed by the conHuence of the splenic andsuperior mesenteric veins. The portal vein therefore rece ives blood fromLhe enLi re digestive tract, spleen, pancreas, and gallbladder. [Barash, Clill.Alles., 5" ed., 2006, p1 073; Stoelting, Hall dbook, 2006, p984064. List 4 roles of the liver in protein meta·bolismThe liver has the following 4 roles in protein metabolism: (1) the liverproduces most proteins. wi th the exception of immunoglobins. (2) theliver synthesizes lipoprotein. (3) the li ver carries out the conversiotl ofamino acids by oxidative deamina tioll into carbohydrates and fatty acidsfor the producLion of A TP, and (4) the liver produces urea in order Loremove ammonia (from the hepatic deamination process and from bacLerial productio n in the gUL). INagelhout & Zaglaniczny, NA, 3rd65. It'What is the most common major complication of cirrhosis?Ascites is the most common major complication of cirrhosis66. It'There are at least three theories describingthe mechanism of ascites formation. Allthree theories have a basic event in common;what is the basic event in the formation of ascites?67. Consider the patient with cirrhotic liverdisease: would you give the same dose, agreater dose, or a lesser dose of nondepolarizingmuscle relaxant to this patient?Cirrhotic liver disease (and renal failure) often results in an increasedvolume of distribution and lower plasma concentrations for a given water-soluble drug, such as muscle relaxants. Furthermore, drugs that dependupon hepatic or renal excretion may have a prolonged clearance.Thus, depending on the drug of choice, a greater initial loading dose. butsmaller maintenance doses might be required in cirrhotic liver disease.Vecuronium, pancuronium, and rocuronium blockade are prolonged byliver disease. [Morgan, Mikhail, and Murray, Clin. Anesthesiol., 4th ed68. Identify the hallmarks of an acute porphyria attack?Hallmarks of acute porphyria attacks are abdominal pain, nausea & vomiting,autonomic disturbances with sweating, tachycardia, sustainedhypertension, and neurological manifestations including seizures andneuromuscular weakness. Attacks can be life-threatening and neurologicalmanifestations may be permanent. [69. Describe renal autoregulation. Whichrenal structure appea rs to mediate autoregulation?Rellal autoregulation is the mechanism by which the kidney maintainsrenal blood flow (RBF) and glomerular filtration rate (GFR) thus preservingsolute and water regulation independently of wide fluctuations inblood pressure. Renal autoregulation typically operates over mean arterialpressures ranging from 60 mm-Hg to 180 mm-Hg (some texts state 80-180 mm-Hg, and others 60- 160 mm-Hg). Renal vascular resistance appearsto be mediated by the va riable resistance of the preglomerular affe- JCrelit arteriole. [Guyton, TMP. lie. 2006 pp323-325; Stoelting, PPAP.70. State and briefly describe two proposedmechanism for renal autoregulation?The most plausible explanations for renal auto regulations are (I) a myogenic response in which the arterioles constrict in response to increasedarterial pressure and vice versa. and (2) tubuloglomerular feedback byway of the juxtaglomerular apparatus. The myogenic response theorysLates that increased wall tension in the afferent arterioles. due to anincrease in perfusion pressure, causes automatic contrac tion of thesmooth muscle fibers in the vessel wall, thereby increas ing res istance toflow, and keeping flow constant despite the increase in perfusion pressure.The tubuloglomerular feedback mechanism proposes that increasedperfusion pressure will increase filtration, increasing the tubular fluiddelivery to the macula densa. which then releases a factor or fac tors thatcause vasoconstriction of the afferent arteriole. [Guyton, TMP. li e. 200671.'Identify the 3 major renal processes.Which of these functions require(s) energy (ATP)?The three major renal tubular functions are filtration, reabsorption, andsecretion. Of these, reabsorption and secretion are active transportprocesses that require energy from ATP hydrolysis. The major energysource for reabsorption of sodium, the key link to most renal transportprocesses, is activity of the Na+ -K+ ATPase (pump). Remember that"pump" implies an active process, costing A TP-derived energy to move asubstance against its concentration gradient. [Guyton, TMP72. Which nephron tubular segment is responsiblefor approximately two-thirds of allreabsorption and secretory processes?Approximately two-thirds of all reabsorption and secretory processes inrenal tubules takes place in proximal tubules73. What is a countercurrent system? Identifytwo countercurrent systems in the human body.A countercurrent system is an arrangement where inflow runs parallel to,counter to, and in close proximity to the outflow for some distance. Thinkof a U-shaped tube to aid the visualization of this arrangement. In thehuman, there are three major countercurrent systems: the loop of Henlein the nephrons of the kidneys, the vasa recta of the kidneys (capillaries ofthe nephrons), and blood flow to the testes through the spermatic arteries and veins74. ft'Compare and contrast a countercurrentmultiplier system with a countercurrentexchange system. Which system(s) is used in the kidneys? The testes?A countercurrent multiplier system, such as the loop of Henle, creates agradient along the flow pathway. Specifically, the loop of Henle creates anincreasing osmotic gradient in the interstitium surrounding the loops,with the maximum osmolality occurring at the tip of the loop of Henle. Acountercurrent exchange system involves a transfer (exchange) of matteror energy between the inflow and outflow limbs. In the kidney, the vasarecta exchange solutes and water with the loop of Henle, maintaining theosmotic gradient in the interstitium. Summary: the kidneys contain bothcountercurrent multipliers (loop of Henle) and countercurrent exchangers(vasa recta). [Ganong, Review of Medical Physiology, 22nd ed., 2005,75. What is the function of the countercurrentsystems in the kidney?The countercurrent multipliers (loop of Henle) and exchangers (vasarecta) allow the kidneys to adjust the osmolality of the urine, that is, todilute or concentrate the urine. [Ganong, Review of Medical Physiology76. What class of drugs causes urinary retentionand thus may interfere with urinary bladder studies? Opioids cause urinary retention, mediated primarily by mu-1 recepto rs.Opioids cause a dyssynergia between the bladder detrusor muscle andurethral sphincter because of failure of sphincter relaxation77. @)State the specificity and sensitivity of thefraction excretion of sodium in distinguishingbetween peerenal azotemia and acutetubular necrosis (renal azotemiaThe sensitivity and specificity of fractional excretion of sodium of <1 % indifferentiating prerenal azotemia from acute tubular necrosis are 96% and 85%78. is the most important determinantof blood viscosity?The most important determinant of blood viscosity is the hematocrit. Adecrease in hematocrit decreases viscos ity and can improve blood flow.However. there is a concomitant decrease in oxygen-carrying capacitywith decreased hematocrit and eventually impaired oxygen delivery79. Fresh frozen plasma (FFP) co ntains allprocoagulant factors except platelets. as youknow. Which factors are most abundant in FFP?Fac tors V and VIII are most labile and are the most abundant factors infresh frozen plasma (FFP).IBarash, Handbook, 5'h ed., 2006, p103: Yao &Artllsio, Yaa & Artusio's Anesthesiology: Problem-Orieflt ed Pa tient Managelllellt,5'h ed., 2003, pp38180. Must fresh frozen plasma (FFP) be ABOcompatible for administration?Yes, fresh frozen plasma (FFP) must be ABO compatible. I Barash, Handbook81. Identify 4 general indications to administerfresh frozen plasma (FFP).Transfusions offresh frozen plasma (FFP) are indicated for: (I) isolatedcoagulation factor deficiencies; (2) reversal of warfarin therapy; (3) correctionof coagulopathies associated with liver disease; and, (4) aftermassive transfusions with continued bleeding even after platelet transfusions82. 'During the preoperative workup, thepatient states they take the herbal supplementgarlic. How long should garlic bediscontinued before elective surgery?The herbal "Gs" (garlic, ginseng, ginkgo, ginger, guarana, and goldenseal)should be discontinued 2 weeks before elective surgery in order to restoreno~al anticoagulation status. Note: Miller states discontinue garlic for 7days prior to elective surgery. [Nagelhout &83. @>What type of muscle is the pyloric sphinc- The pyloric sphinc ter is a short, relative poor barrier of smooth muscleter? between the stomach and the duodenum. IBoron, Med Physiol. 2e. 2009pp89084. lWhat type of muscle is found in the gaostrointestinal tract? Identify the arrangement of this muscle in the GI traclThe tunica muscularis of the gastrointestinal tract is comprised of two layers of smooth muscle: the inner layer is circular, the outer layer islongitudinal. Specialized circular muscles are called sphincters. [Boron,Med Pltysiol. 2e. 2009 pp890-891; Guyton, TMP. li e. 2006 pp77l. 773185. What is the gastric pH (range) in the fasted patient?Gast ric pH in the fasted patient ranges from 1.6-2.2. I Kirby. Clill. Alles.Practice, 2"d ed .? 2002, pl9186. ?List the electrolyte distu rbances asso ciated with anorexia nervosa.Anorex ia nervosa is characterized by hypokalemia, hyponatremia, hypochloremia,and metabolic alkalosis as a res ult of vomiting and laxative& diuret ic abuse. IHines.87. Identify the two types of acquired im munityAcquired immunity is the result of lymphocyte activity and is class ifiedinto humoral and ce/l-mediated immunities88. ",What specific lymphocyte class mediateshumoral immunity? Cell -mediated immunityHumoral immunity is mediated by B lymphocytes whereas T lymphocytesare responsible for cell -mediated immunity. B lymphocytes get theirname from the origin al discovery of these cells in the bursa of birds. Tlymphocytes are so-named due to their pre-processing and maturation inthe thymus gland. IGuyton. TMP. li e. 2006 pp440-443; Stoelting. PPAP.89. List two types of mature B lymphocytesand 4 types of mature T lymphocytesDifferentiated (mature) B lymphocytes may be either memory ceUs orplasma ce/ls. Mature T lymphocytes are either T-helper (CD4). Tsuppressor(CD8). T-cytotoxic/killer (CD8). or T-memory cells. [Guyton.TMP. li e. 2006 pp440-443; Stoelting. PPAP. 4e. 2006 pp856- 858190. Which lymphocytes are the so urce ofimmunoglobulins (lg)?Mature B lymphocyte plasma cells are the source of the gamma globulinsknown as immunoglobulins. [Guyton. TMP. li e. 2006 pp440- 443; Stoelting.PPAP. 4e. 2006 pp856-858191. Usllhe 5 types of immunoglobulins inthe serum. Approximately what perce ntageof total serum proteins are immunoglobulinsThe 5 classes of immunoglobulins are IgG. IgA. IgM. IgD. and IgE. coll ectivelyaccounting for approximately 20% of total serum proteins92. During an aorta-femoral bypass, thepatient becomes hypothermic; what cardiac arrhythmia is likely?Hypothermia prolongs the refractory period of excitable tissues. In the heart, aprolonged refractory period leads to sinus bradycardia and conduction defici ts,which may progress to at rioventricular block and eventually ventricular fibril lalion.INagclhout & Zaglaniczny, NA, 3rd cd., 2004, p 11 47193. Identify 6 physiologic disturbancescaused by hypothermia.Hypothermia causes the follOwing 6 physiologic disturbances: (1) theoxyhemoglobin curve is left-shifted-affinity for oxygen is increased andoxygen will not be as readily released to the tissues; (2) shivering increasesoxygen demand by 400-500%; (3) metabolically-dependent processes,such as drug biotransformation, are slowed; (4) glomerular filtration ratedecreases; (5) central nervous system depression may be profound; and.(6) cardiac rate and rhythm disturbances, specifically bradycardia andpremature ventricular contractions occur more frequently. [Nagelhout &94. What endocrine disorder is associatedwith small cell lung carcinoma (SCLC; Oatcell carcinoma)?Small cell lung carcinoma (SCLS; Oat cell carcinoma) accou nts for 15-25% oflung cancers and is associated with (1) syndrome of inappropriateADH seeretioll (SIAOH). (2) ectopic corticotropin secretion. and (3) Eaton-Lambert syndrome. [Stoelting & Oierdorf. Handbook of Anesthesia95. Describe tl,e pulmonary mec hanics alterationslhat occur in the patient with endstage scoliosis.The main alterations in lung mechanics of the patient with end-stage scoliosis arereduced lung volumes (Ve. TLC. FRC. and RV-aU restrictive process featu res)and reduced chest wall com·pliance. In the late stages of scoliosis. V/Q mismatchingwith hypoxia (due to alveolar hypovell tilation). increased PAP. hypercapnia.abnormal ventilatory COl response curve. increased work of breathing, and corpulmonale occur. c\'entually leading to card iorespiratory failure.INagelhout96. What is a dose-response curve?A dose-response curve depicts the relationship between the dose of a drugadministered (x-axis) and the resulting pharmacologic effect (y-axis97. List four (4) descriptive characteristics of a dose-response curve.Dose-response curves are characterized by differences in (1) potency, (2)slope. (3) efficacy. and (4) individual variability. (The graph in Stoelting isinvaluable). IStoelting. PPAP. 4e. 2006 pp 17; Miller98. Descrihe how potency of a drug is depictedby the dose-response curveThe potency of a drug is depicted by its location along the dose axis(usually the x-axis) of the dose-response curve. Increased affinity of adrug for its receptor shifts the curve to the left, whereas decreased affinityshifts the curve to the right. Drug potency and receptor affinity are directlyrelated-a more potent drug has a greater affinity for its receptor.Mnemonic: Left-shift = Less drug required = More potent. [Sto99. What does the slope of a dose-responsecurve reveal about the drug?The slope of the dose-response curve indicates the number of receptorsthat must be occupied (bound) before a drug effect occurs. A steep doseresponsecurve slope means that a majority of the receptors must bebound before a relevant effect occurs. Neuromuscular blocking drugs andinhaled anesthetics dose-resportse cu rves have steep slopes100. Deftne drug efficacy. Which feature of adose -response curve indicates the efficacy of a drug?Efficacy is a measure of the intrinsic ability of a drug to produce a givenphysiologic or clinical effecl. In other words, the maximal effect of a drugreflects its intrinsic activity, or efficacy. A drug's efficacy is depicted by theplateau of the dose-response curve. A higher plateau correlates with a greater efficacy101. Describe how the presence of a competi·tive antagonist would alter a dose-responsecurve of a drug.The presence of a competitive antagonist (inhibitor) would shift the doesresponsecurve to the right, with no change in the efficacy (plateau) orslope. The rightward shift is caused by competition for the same numberof receptors. IMiller. Anesthesia. 6e. 2005 pp96; Barash. Clinical Alles ..102. t"Describe how the presence of a noncompetitiveantagonist would alter the doseresponsecurve of a drug.The presence of a noncompetitive antagonist (inhibitor) would shift thecurve rightward and downward, with a decrease in the slope of the curve.The changes occur because a maximal effect cannot be achieved in thepresence of a noncompetitive block. In other words, a noncompetitiveblock cannot be reversed by excess agonist. [Miller, Anesthesia. 6e. 2005pp96; Barash. Clillical Alles .. se. 2006 pp96s0103. Which volatile agent is completely halogenatedwith fluorine?Desflurane, a methyl ethyl ether, is completely halogenated with fluorin e.Even though sevoflurane has only fluorine as the halogen substitutions.sevoflurane is not considered completely halogenated. [Barash, Clin.104. IIWhich volatile agents most depress thebaroreceptor reflex, and which least depress it?HaiotJratlc and sevojlurane most depress the baroreceptor reflex (there areno increases in heart rate despite decreases in blood pressure wi th theseagents). Depression of the baroreceptor response by sevoflurane is comparableto halothane. In co ntras l, isoJ1urane and des flurane least depressthe baroreceptor reflex (heart rate tends to increase reflex.1y with lhedecreases in blood pressure produced by these age nts). IStoelting105. You know that ketamine binds to NMDAtypeglutamate receptors ... which class ofanesthetic drugs also binds to ionotropicglutamate receptors and then inhibits glutamatergic neurotransmission?Barbiturates bind to ionotropic glutamate receptors and inhibit neurotransmissionof the excitatory neurotransmitter glutamate. [Miller106. Rank opioids from most La least lipid soluble.The order of opioid lipid -solubility ranked from most to least: sufentanil(1778) >> fentanyl (955) >>> alfen tan il (145) ?> meperidine (39) >remifentanil (17.9) > morphine (1.9). NB: The numbers in parenthesesare the octanol/H20 coefficients, a measure of lipid solubility107. Which opioid should not be given with aneuraxialtech nique? Why?Remifentanil should not be administered inlrathecally or epidurally, asthe safety of the buffering vehicle has not been determined. The bufferingvehicle is glycine. which is an inhibitory neurotransmitter. [Stoelt ing.108. "What additive is found in etomidate(Amidate)? What problem may this additivecause?Etomidate (Amidate) is provided as an aqueous solution of 0.2% etomidateand 35% propylene glycol. Propylene glycol may cause pain on injection.(See MemoryMaster IB3e:Q25 for other drugs formulated with propylene glycol109. Is there a new formulation of etomidatethat is propylene glycol-free? What is thenew formulation of etomidate?Etomidate-Lipuro is a new lipid emulsion formulation of etomidate. Thelipid emulsion formulation minimizes pain on injection. [Stoelting,Handbook,2006,p164}110. Which intravenous anesthetic agent isadministered as a single isomer?Etomidate (Amidate) is administered as a single isomer (the D-isomer,specifically). [Barash, Clin. Anes., 5th ed.,111. In addition to metabolism in the liver,propofol undergoes an ex trahepatic foute ofelimination. Identify the ext rahepatic route of elimination of preparo!.The lungs seem to play an important role in the ext rahepatic metabolismof propofol. The lungs are responsible for approximately 30% of the uptakeand first-pass elimination after a bolus dose of propofol. Note: for adrug that is eliminated by hepatic metabolism, if the clea rance rale exceedshepatic blood flow, an extrahepatic route of elimination also contri butesto the drugs clearance. IMiller, Anestiresia112. Is propofoI a weak acid or a weak base?Propofol is a weak acid113. lWhat is the maximal safe dose of cocainewhen applied nasally or topically?The maximum dose of cocaine is 200 mg for a 70 kg individual, or 3mglkg (Barash). Stoelting states 150 mg is the single maximum does ofcocaine. NO: be aware of the conflict with Omoigui's Anesthesia DrugHatldbook. which states 1.5 mg/kg is the "maximal safe dose of cocain e".{Barash, Clill. Alles .. 6". 2009 pp1 32B; Stoelt ing, PPAP. 4e. 2006 pp 195;Omoigui, Omoigui's Anestltesia Drugs. 3e. 1999 pp59J114. Which local anesthetics are chiral drugs(possess ing an asymmetric carbon center)?The pipecoloxylid ide local anesthetics (mepivacaine, bupivacaine. ropivacaine.levobupivacaine) are chiral drugs because their molecules possessan asymmetric carbon atom. As such. these drugs may have a left (S) orright (R) handed configuration. Molecules that are stereospecific superimposable mirror images of each other and called enQlItiomers. Enantiomersare optically act ive-they rotate plane polarized light.IStoelti115. Which two local anes thelics are ad ministeredas racemic mixtures (50:50 mixture of enantiomers)?Mepivacaille and bllpivacaine are available for clinical use as racemicmixtu res (50:50 mixture) of the enantiomers. The enantiomers of a chiraldrug may vary in their pharmacokinetics, pharmacodynamics. and toxicity.Administering a racemic drug mixture is. in reality, the administration of two difTerent drugs116.ldentify tl,e two local anesthetics that arepure S ellantiomers. What is the advantage of these local anesthetics?Ropivacaine and levobupivacaine have been developed as pure S enanHomers(they are not racemic mixtu res). These S enantiomers produceless neurotoxicity and cardiotoxicity than racemic mixt ures or the Renantiomers of local anesthetics. perhaps reflec ting decreased potency at sodium ion channels117. K'Narne the two active metabolites producedby lidocaine metabolismMonoethylglycinexylidide (MEGX) and glycine xylidide (GX) are theactive products ofl idocaine metabolism by liver microsomal P450 sys tem.118. Is there an active metabolite of succinylcholine?Yes. Succinylmonocholine is a much weaker metabolite of succinylcholine,but succinylmonocholine is metabolized much more slowly to succinicacid and choline. (Revises MemoryMaster IBSa:Q9.) [Miller, Anesthesia119. All nondepolarizing muscle relaxants areclassified as either benzylisoquinoliniwns orsteroid derivatives. Which nondepolarizingmuscle relaxants are benzylisoquinoliniumsand which are steroid derivatives?All nondepolarizing muscle relaxants with "curium" in their name arebenzylisoquinoliniums. Thus, mivacurium, atracurium, cisatracuriwn,doxacuriwn, as well as d-tubocurarine and metocurine are benzylisoquinoliniums.The nondepolarizing muscle relaxants with "curonium" intheir name are all steroid derivatives. Vecuronium, rocuronium, pancuronium,and pipecuroniwn are steroid derivatives120. vWhich two nondepolarizing neuromuscularrelaxants have active metabolites? Comparethe activity of the metabolites to the parent compound.Vecuronium and pancuronium have active metabolites. specifically the 3-hydroxy (3-0H) metabolites (3-desacetylvecuronium and 3-desacetylpancuronium). The 3-desacetlyvecuronium metabolite is about50-70% as potent as vecuronium. whereas 3-desacetylpancuronium hasabout 50% potency of pancuronium at the neuromuscular junction. [Barash.Clill. Alles .. 5,h ed .. 2006. p436; Miller. Anesthesia. 6" ed .? 2005.121. Carbamazepine (Tegretol) is an antiseizuremedication that works by stabilizingsodium channels in the inactive conformation(closed and inactive = no action potentials).What effects may carbamazepine haveon nondepolarizing muscle relaxantsNondepolarizing muscle relaxants may have a shorter duration thanexpected in the patient receiving chronic carbamazepine therapy. Specifically,vecuronium clearance is increased 2-fold in the patient receivingchronic carbamazepine therapy. Anticipate increased dosing and shorterduration for nondepolarizing muscle relaxants. [Miller, Anesthesia, 6thed., 2005, p517; Waugaman, Principles and Pra122. ,Postoperative muscle pain due to skeletalmuscle fasciculations is a common problemafter succinylcholine administration. Howmay you minimize the postoperative skeletalmuscle pain following succinylcholine administration?In order to minimize fasciculations associated with succinylcholine andsubsequent postoperative skeletal muscle pain, a defasciculating dose(10% to 15% of intubating dose) of nondepolarizing muscle blocker maybe administered 5 minutes prior to the succinylcholine administration.Tubocurarine and rocuronium appear to be particularly effective at minimizingSUCcinylcholine-induced fasciculations, but tubocurarine is nolonger available for use in the U.S. Therefore, rocuronium 0.03-0.04mglkg (10% ED95) administered 5 minutes prior to succinylcholine administrationis particularly effective at preventing fasciculations. Atracurium0.02 mglkg is also effective for this application. NB: "Self-taming,"the administration of a small dose (10 mg) of succinylcholine 1 minutebefore intubation does not appear to be effective in preventing fasciculations123. What is the appropriate premedicationdose of atropine for the adult with severe bradycardia?As a premedication, atropine is administered intravenously or intramuscularlyin a range of 0.01-0.02 mg/kg up to the usual adult dose of 0.4-0.6mglkg. Larger intravenous doses up to 2 mg may be required to completelyblock the cardiac vagal nerves in treating severe bradycardia Omoiguistates: "0.5-1.0 mg IV/IM/SC, repeat every 3 to 5 minutes as indicated."[Morgan, Mikhail, and Murray, Clin. Anesthesiol., 4th ed., 2006, p239124. Identify the incidence of heterozygousatypical plasma cholinesterase (EuEa) in thegeneral population. Identify the incidence ofhomozygous atypical plasma cholinesterase(EaEa) in the general populationThe incidence of heterozygous atypical plasma cholinesterase (EuEa) inthe general population is about 1 :25, or 4%. The incidence of homozygousatypical plasma cholinesterase (EaEa) in the general population is about1:2800, or 0.04%. Two comments: (1) the incidence varies by text reference-496 and 0.04% represent reasonable averages; (2) review of table20-9, page 324 in Barash Handbook is highly recommended125. l'Which of the 4 common anticholinesteraseagents is not a quaternary ammonium?Physostigmine is a tertiary amine. Edrophoniurn, neostigmine, and pyridostigrnineare all quaternary amines. Remember: physostigmine is notused to reverse neuromuscular blockade because the dose required toachieve this effect is excessive. Nonetheless. physostigmine is an anticholinesterase126. 'Rank order the anticholinesterase andanticholinergic agents based on onset (inminutes), from fastest to slowestThe order of onset (in minutes) for anticholinergic and anticholinesteraseagents, from fastest to slowest is: atropine (1-2 min), glycopyrrolate (2min), edrophonium (5-10 min), neostigmine (5-15), and pyridostigmine(10-20).127. Rank order anticholinesterase and anticholinergicagents based on duration (inminutes), from shortest to longest.The order of duration (in minutes) for anticholinergic and anticholinesteraseagents. from shortest to longest, is: edrophonium (30-60 min) <neostigmine (45-90 min) < atropine (60-120 min) = pyridostigmine (60-120) < glycopyrrolate (120-240128. Give 6 contraindications/cautions toesmolol administration.Esmolol is contraindicated-or should be used with caution (textbookvariations)-in the follOwing 6 patients: (1) with sinus bradycardia; (2)with AV heart blocks, especially greater than first degree; (3) with chronicobstructive pulmonary disease; (4) hypotensive; (5) with cardiogenicshock; and, (6) with cardiac failure. [Morgan, et al., Clin. Anesth .. 4e. 2006129. The alpha-2 adrenergic receptor agonist.c1onidine, acts where centrally to producewhat therapeutic effect?Stimulation of alpha-2A reccptors of inhibitory neurons in the vasomotorcenter of the medulla in the brain stem inhibits sympathetic nervoussystem outflow. This action dec reases blood pressu re.130. Alpha-2 adrenergic receptor agonistsantagonize the sympathetic nervous sys tempe ripherally. How?Alpha-2 receptors are found peripherally in the surface membrane of thenorepinephrine-containing presynap tic nerve terminals of sympatheticpostganglionic neurons. Stimulation of t~ese receptors decreases therelease of norepinephrinc from the presynaptic nerve terminal. Thisdecreased release of norepinephrine contributes modestly Lo the clonidine-induced decrease in blood pressu re.131. Sodium nitroprusside contains 5 cyanideions (CN-) and may cause cyanide toxicity,as you know. What three reactions maycyanide ions (CN-) undergo?Cyanide ions (CN-) may react in three ways: (1) binding to methemoglobinto form cyanomethemoglobin, (2) reaction with thiosulfate in theliver to produce thiocyanide, catalyzed by rhodanese, and (3) binding totissue cytochrome oxidase, which interferes with normal oxygen utilizationby the tissues. [Morgan, Mikhail, and Murray132. How do cyanide ions interfere with oxygenutilization at tissue cytochrome oxidase?Binding of cyanide ions to tissue cytochrome oxidase uncouples oxidativephosphorylation, preventing the formation of ATP133. List the four hallmark signs and symptomsof cyanide toxicityAcute cyanide toxicity is characterized by (1) metabolic acidosis (basedeficit), (2) cardiac arrhythmias, (3) increased venous oxygen content dueto inhibition of cytochrome oxidase and consequent inability of cells toutilize oxygen, and (4) tachyphylaxis.134. The patient administered sodium nitroprussidecontinuously (by drip) presentswith the following arterial blood gases(ABGs): pH = 7.21, P.C02 = 32 mm Hg, P.02= 104 mm Hg, base excess = -10 mEqIL.What is your next action? Explain the arterial blood gases.Turn off the nitroprusside drip. These ABGs suggest cyanide toxicity. Thebase excess of -10 mEq/L (base deficit of 10 mEq/L) demonstrates thatthe acidosis is metabolic. The low PaC02 of32 mm Hg demonstratespartial respiratory compensation of the metabolic acidosis135. What is your concern with giving phenytoin(Dilantin) to the hyperglycemic patient?Phenytoin (Dilantin) partially inhibits (blunts) insulin release and maylead to increased blood glucose levels in patients who are hyperglycemic136. Describe the metabolism and eliminationof adenosine (Adenocard).Adenosine is rapidly eliminated by enzymatic clearance (less than oneminute). Specifically, adenosine is deaminated in the plasma forminginosine, or is taken up in erythrocytes (RBCs) and vascular endothelialcells where it is metabolized to inosine (by deamination) or adenosinemonophosphate (by phosphorylation). 137. D escribe the mechanism of action ofinamrinone (Inocor) and milrinoneInamrinone (Inocor) and milrinone (Primacor) are phosphodiesterase(PDE) inhibitors. specifically, selective POEm inhibitors. POEm is cAMPspecific,thus inamrinone and milrinone will result in increased cAMP incells. As you know, the golden rule of signal transduclion is "secondmessengersare tissue specific." The two major effects of inamrinone andmilrinone occur in the hea rt and in the vasculature. In the heart. in creasedcAMP produced increased inotropy (cAMP is a chemical; chemicalsalter contractility) whereas in the smooth muscle of the vasculaturein creased cAMP promotes smooth muscle relaxalion, vasodilation andthus decreased systemiC vascular resistance (SVR). Both inamrinone andmilrinone may be called "inodilators" and are not dependent upon adrenergicreceptors ror th eir actions. [Stoelting, PPAP, 4'h ed., 2006, pp236138. What potential side effect occurs withinamrinone, but not with milrinoneInamrinone (Inoco r) can produce thrombocytopenia with long-termtherapy. Milrinone (Primacor) does not produce any apparent effec ts onplate1ets.[Nagelhout & Zaglaniczn139. During, what time frame should warfarin be discontinued prior to surgery?Warfarin should be discontinued 3-5 days prior to surgery140. In preparation for surgery, when shouldthe last dose of low molecular weight heparin (LMWH) be given?The last does oflow-molecular-weight heparin (LMWH) should be given12 hours before the procedure. [Stoelting & Miller, Basics, Slh ed., 2007,p343]141. After the surgical procedure, when shouldheparin be restarted?Heparin should be res tarted 12 hours after the surgical procedure, even inhigh-risk patients, because the risk for severe hemorrhage is substantial142. Following a dose oflow-molecular-weightheparin, when can a neuraxial intervention be performed?Neuraxial interventions should be delayed 10-12 hours after a dose oflow-molecular-weight heparin. [Stoelting143. Iff a neuraxial catheter is in place and adose of heparin is given, how long shouldyou wait before removing the catheter? Howlong should you wait before administering the next dose of heparin?Ncuraxial catheter removal is acceptable 2 to 4 hours after heparin dosingAND with normal PTf' or ACT. Wait 1 hour after catheter removal toadminister a repeat dose of heparin. [Stoelting144. Jf a neuraxial catheter is in place and adose of low-molecular-weight heparin(LMWH) is given, how long should you waitbefore removing the catheter? How longshould you wait before administering the next dose of LMWH?Neuraxial catheter removal is acceptable 10 to 12 hours after the last doseoflow-molecular-weight heparin. Wait 2 hours after catheter removal toadminister the next dose ofLMWH145. @List eight (8) deleterious effects of methyleneblue administration.Methylene blue may cause (I) destruction of RBCs with prolonged use,(2) hypertension, (3) urinary bladder irritation, (4) nausea, and (5) diaphoresis.Methylene blue (6) may inhibit nitrate-induced coronary arteryrelaxation, (7) interferes with pulse oximetry for 1-2 minutes, and (8) cancause hemolysis in patients with glucose-6-phosphate dehydrogenasedeficiency. [Dunn, et aI., Mass. Gell .. 7e. 2007 pp740146. List one advantage and one disadvantagethat antacids have over H2-receptor antagonistsfor premedication of patients with a potential full stomachAntacids have an immediate effect, compared to the delayed onset ofeffects of Hrreceptor antagonists. Unfortunately, antacids increase gastricvolume, unlike H2-receptor antagonists. [Morgan147. Give two advantages and one disadvantagethat nonparticulate antacids posses,compared to particulate antacidsNonparticulate antacids (sodium citrate or sodium bicarbonate) are muchless damaging to lung alveoli if aspirated, compared to particulate antacids.Nonparticulate antacids also mix with gastric contents better thanparticulate antacids. Nonparticulate antacids, however, lose their effectiveness30-60 minutes after ingestion, so timing of administration iscritical. Nonparticulate antacids should be given immediately prior to induction.148. What diuretic can cause ototoxicity (deafness),especially in patient with renal insufficiencyLoop diuretics, especially furosemide, may cause ototoxicity particularlyin patients with renal insufficiency. This transient or permanent sideeffect is most likely to occur with prolonged increases in the plasma concentrationof these drugs in the presence of other ototoxic drugs. [Barash,Clin. Anes .. 61h? 2009 pp1359; Stoelting, PPAP. 4e.149. Bleomycin is Loxic to what body organ?Why does bleomycin accumulate in this organ?Bleomyci n, an antibiotic/chemotherapeutic, is toxic to the pulmonarysys tem. Bleomycin is concentrated preferentially in the lung because theenzyme that inactivates bleomycin (hydrolase) is relatively deficienl inlung tissue. [Barash, Ciin. Alles., 1997, ppI219- 1223; Stoelting, PPAP,150. ? Describe phospholipase A, (PLA,).Phospholipase A2 (PLA2) is the rate-limiting enzyme that catalyzes thelibera tion of arachidonic acid from membrane phospholipids. The liberationof arachido nic acid is the first step in the production of prostaglandins.leukotrienes. and thromboxanes (and other substances. too}.151. @)HowdocorticosteroidsalterphospholipaseA2 (PLA2), ultimately leading to reduced inflammation?Steroids decrease inflammation by inducing the biosynthesis of aPLA2inhibitor and preventing subsequent prostaglandin generation.[Cousins, Neural Blockade152. Statins {atorvastatin (Lipitor), fluvastatin(Lescol), lovastatin (Mevacor), pravastatin(Pravachol), and simvastatin (Zocor)} aresome of the most commonly-prescribeddrugs in the general population. How do statins work?Statins are drugs that act as inhibitors ofHMG-CoA reductase, the ratelimitingenzyme in cholesterol biosynthesis. HMG-CoA reductase catalyzesthe conversion of the substrate HMG-CoA to mevalonate. The resultinginhibition of cholesterol synthesis is accompanied by decreases (up to60%) in LDL ("bad") cholesterol. (HMG-CoA is hydroxymethylglutarylcoenzyme A). [Stoelting, PPAP. 4e. 2006 pp587153. What are the two most-feared side effectsof statin administration? What laboratorytests should be requested for the patient taking statins?The two most-feared side effects of statin therapy are (1) liver dysfunctionwith elevated haptic enzymes, and (2) severe myopathy with the possibilityof rhabdomyolysis, myoglobinuria, and acute renal failure. Liver functiontests should be performed, up through the morning of the surgery154. Propofol, a weak acid, has a pKa of 11.0. Ispropofol mostly ionized or mostly unionizedat normal physiologic pH 7.4? Will the dominantform readily cross membranes or or notSince the normal physiologic pH 7.4 is less than the pKa 11.0 of propofol,the body environment is an acidic environmentfor the weak acid propofol.Remember, the pKa of a given substance is "dividing mark" for acidicand basic environments. The mnemonic is "acids + acids ~ moreunionized", therefore propofol will be mostly nonionized at physiologicpH 7.4. The unionized form of a substance is lipid-soluble and thus readily crosses the membrane155. Where is glycogen stored in the humanbody? How long will glycogen stores supply glucose during starvation?Glycogen is stored in skeletal muscles (400 g) and in the liver (100 g). Theglycogen sto res will supply about 24 hours of glucose during starvationco nditions (G uyton says 12 hours). After glycogen stores are depleted,gluconeogenesis in the liver becomes an increaSingly important source ofglucose. IGanong. Review of Medical Physiology. 22" ed .. 2005. p291. 298156. N'Which cell membrane receptor involvedin carbohydrate metabolism is a receptortyrosine kinase? Describe the function of a receptor tyrosine kinase.The insulin receptor is a receptor tyrosine kinase (RTK), a specific type ofenzyme-linked receptor. Insulin-mediated stimulation of the tyrosinekinase activity, which is necessary for normal function of insulin receptors,is impaired in non-insulin-dependent diabetes mellitus (NIDDM).The insulin receptor is a tetramer of 2 alpha and 2 beta subunits (a2~2);the cytoplasmic tails of the membrane-spanning beta subunits possess the tyrosine kinase activity. Insulin binding stimulates autophosphorylationof the bela subunits (kinases add phosphates to substra tes). which thenpromotes phosphorylation of downst ream targets. See Guyton figure 7S-3for a good visual aid. IGuyton & Hall. TMP. II 'h cd .? 2005. pp962-963;Ganong. Review of Medical157. What effect does hypothermia have on gas solubility'?As a liquid is cooled. more gas dissolves in the liquid; therefore hypothermia will cause an increase in gas solubility. IParb rook, p8 I; Miller,Anesthesia. 1994. pp1370158. What is Dalton's law?Dalton's law of partial pressures states that the total pressure (TP) of agroup of gases is equal to the sum of their individual partial pressures.Mathematically, Pleta! = PI + Pz + Pl. [159. @)What is heat of vaporization? What is thelatent heat of vaporization?The phase change from the liquid state to the gaseous state is called vaporization.It takes energy for the molecules in a liquid phase to break awayand enter the gaseous phase. A liquid's heat of vaporization is the numberof calories (a measure of energy) necessary to convert 1 mL liquid into avapor. The latent heat of vaporization is more precisely defined as thenumber of calories required to change 1 g of liquid into vapor without a temperature change160. If atmospheric pressure is 710 mmHg,and the Oz:NzO delivery is 2L:4L (6L totalflow), what partial pressure of Oz and whatpartial pressure ofNzO are delivered to thepatient? Whose law permits these calculations ?One-third (2/6 = 33.3%) of the delivered gas is Oz, and two-thirds (4/6 =66.7%) is N10. POz = 0.333 x 710 mmHg = 236 mmHg; PN20 = 0.667 x710 mmHg = 474 mmHg. Dalton's law of partial pressures permits thesecalculations to be made. [West, Respiratory PhYSiology, 1990, p164]161. @What happens to the temperature of aliquid as vaporization occurs?Since vaporization requires energy, the temperature of a liquid decreasesas vaporization proceeds. As the liquid temperature falls, a gradient isestablished between the liquid and the surrounding environment. Energyflows from the warmer area (surroundings) to the cooler area (liquid)thisflow of thermal energy is called heat. At some point, an equilibrium isreached at which the energy lost (heat) to vaporization is matched by theenergy supplied from the surroundings (heat). [Dorsch, UAE.162. @Describe what may happen to vapor pressureif a carrier gas flows through the vaporizer containerAs a flow of gas (carrier gas) passes through the vaporizer container,molecules of vapor are carried away. This causes the equilibrium to shiftso that more molecules enter the vapor phase. Unless some means of supplyingheat is available. the liqUid will cool. As the temperature drops, sodoes the vapor pressure of the liquid, and the carrier gas will pick upfewer molecules so that there is a decrease in concentration in the gas flowing out of the container163. A full E-cylinder at 800 psi is connected toa delivery system set to provide 2 L/min.How long will the E-cylinder supply provide this flow rate?A full E-cylinder contains 625 liters at 2200 psi. As a first approximation,there is about 113 the Original volume remaining, since 800 psi is about113 of 2200 psi. Since the volume-pressure relationship is essentiallylinear, there should be about 1/3 the original volume as well, or approximately208 liters of gas remains in the cylinder. A volume of208 L runningat 2 L/min will provide approximately 104 minutes of gas at this flowrate. Specifically, there are 225 L of gas in the cylinder at a gauge pressureof800 psi: . At a flow rate of2 Umin, the cylinder with 225 L of gas will provide flow for 112.5 minutes164. @ldentify thefour(4)componentsoftheanes thesia gas machine that are exposed tohigh pressures (cylinder pressure).The four components of the anesthesia gas machine that are exposed tohigh-pressure (cylinder pressure) are: ( I) hanger yoke, (2) yoke blockwith check valves, (3) cylinder pressure gauge, and (4) cylinder pressureregulators. INagelhout, NA. 4'h 2009 pp268; Dorsch, UAE. 5e. 2008 pp86165. @ldentifytheeight(8)componentsoftheanesthesia gas machine that are exposed tojtltermediate pressures (pipeline pressure, 50 psi)The eight components of the anesthesia gas machine that are exposed tointermediate pressures (pipeline press ure, SO psi) are; (I) pipeline inlets,(2) check valves, (3) pressure gauges, (4) ve ntilator power inlet, (5) oxygenpressu re-failure device, (6) flowmeter valve, (7) oxygen second-stageregul ato r, and (8) flush valve.INagelhout, NA. 4,h 2009 pp268; Dorsch,166. @ldentifythefour (4) components of theanesthesia gas machine that are exposed tolow pressures (d istal to flowmeter needle valve)The four components of the anes thesia gas machine that are exposed tolow pressures are all distal to the flowmeter needle valve. The componentsare: (I ) flowmeter tubes, (2) vapo rizers, (3) check valves, and (4) commongas outlet. INagelhout, NA. 4,h 2009 pp208167. Why do some modern gas machines have2 flowmeter tubes whereas other machines have one flowmeter tube?The flowmeter arrangement on modern gas machines must account forboth low and high flow rates. A machine with 2 flowmeter tubes in series-one for low flow rates and one for high flow rates-allows a singleflowmeter to indicate both high and low flow rates. A machine with asingle flowmeter tube actually has dual tapers in the tube-one to accuratelyreflect low flow rates and the other for high flow rates. (Recall thatthe Thorpe tube flowmeter is a tapered tube.) Memory phrase: Singletaper7dual tubes or dual taper7single tube. [Morgan, Mikhail, andMurray, CUn. Anesthesiol .? 41h ed., 2006. pS8; Dorsch & Dorsch. UAE168. @)What is the function of an auxiliary flowmeteron the gas machine? What is theadvantage of an auxiliary nowmeter?Auxiliary flowmeters are useful for attaching supplemental oxygen deliverydevices, such as a nasal can nula, to the gas machine. The auxiliaryflowmeter is adva ntageous because the breathing circuit and gas deliveryhose remain intact while supplemental oxygen is delivered to a spontaneouslybreathing patient. Another advantage is that an oxygen source isreadily available for the Ambu bag if the patient needs to be ventilatedmanually for any reason during the case. [Nagelhout. NA. 4,h 2009169. ?What is the primary disadvantage of anauxiliary nowmeter?If pipeline supply has lost pressure or has been contaminated, the auxiliaryflowmeter becomes unavailable. Another disadvantage is that thefraction of inspired inspiration cannot be varied with the auxiliary flow·meter170. Calibration of flowmeters is based uponwhat physical property of gases: density or viscosity?Flowmeters are calibrated for specific gases based upon the gas viscosity('/) at 10 IV flolVs and the gas density (p) at high flolVs. Recall that with lowflow rates, laminar flow is typically favored and the fluid viscos ity is a keydeterminan t oflaminar flow. At high flow rates turbulent flow is morelikely and the fluid density effects the flow. [Morgan. et aI .? Clill. Allesth ..4e. 2006 ppS8; Barash. Clillical Alles .. se. 2006 ppS66-S67)171. 'What is the transport ("T") dial setting ona Drager Vapor 20.n gas machine? What isthe equivalent of this on other gas machines?The Drager Vapor 20.11 gas machine has a transport ("T") dial setting thehelps prevent tippillg·related problems. This [unction is provided by thevaporizer cassette systems of other modern gas machines172. 'What sys tem preven ts filling a vaporizer with the incorrect agent?The keyed filling port sys tem on modern vaporizers prevents filling withthe incor rect agent. [Morgan173. @)Which vaporizer is a "dual-circuit" gasvaporblender? To what feature does the"dual-circuit" apply?The Tec 6 vaporizer is an electrically heated, thermostatically controlled,constant-temperature, pressurized, electromechanically coupled dualcircuit, gas-vapor blender. The pressure in the vapor circuit is electronicallyregulated to equal the pressure in the fresh gas circuit. At a constantfresh gas flow rate, the operator regulates vapor flow using a conventionalconcentration control dial. When the fresh gas flow rate increases, theworking pressure increases proportionally. For a given concentrationsetting even when varying the fresh gas flow rate, the vaporizer output isconstant because the amount of flow through each circuit remains proportional.174. 'The Tec 6 desflurane vaporizer is a dualgasblender, as you know. What are theimplications of this type of vaporizer when a change in altitude is encountered?Because the Tec 6 vaporizer is a dual-gas blender, the Tee 6 will maintaina constant concentration of vapor output (% v/v), not a constant partialpressure, regardless of ambient pressure. This means that at high altitudes,the partial pressure of desflurane (P des) will be decreased in proportionto the atmospheric pressure. The Tec 6 vaporizer requires manualadjustment of the concentration control dial at altitudes other than sealevel to maintain a constant Petes. [Barash, Clin. Anes .. (jib. 2009 pp667-175. What is ti,e main function of the checkvalve(s) in a gas machine?Check valves, also called unidirectional or one-way valves. prevent retrogradeflow (back flow) during pOSi tive pressure ventilation, thereforeminimizing the effects of downstream intermittent pressure fluctuationson inhaled anesthetic concentration. [Dorsch, UA?. 5e. 2008 ppllO176. Describe the purpose of the fail-safe valveon the anesthes ia machineThe fail -safe valve prevents the delivery of hypoxic gas mixtures from themachine in the event offailure of the oxygen supply. The fail -safe valvegoes by Illany other names- the oxygen failure safety valve, oxygen failuresafety device, low-pressure guard ian sys tem, oxygen failure protection device. pressure sensor shutoff system or valve, pressure sensor system,and nitrous oxide shutoff valve. [Miller &177. What are your actions when the oxygenlow-pressure alarm sounds?When the oxygen low-pressure alarm sounds-indicating profound lossof O2 pipeline pressure-fully open the E cylinder, disconnect the pipeline,and consider use oflow fresh gas flows. [Nagelhout178. What is the proportioning system on the anesthesia workstation?A proportioning system on the anesthesia workstation is a hypoxia preventionsafety device. Manufacturers equip anesthesia workstations withproportioning systems in an attempt to prevent creation and delivery of ahypoxic mixture. Nitrous oxide and oxygen are mechanically and/orpneumatically linked so that the minimum oxygen concentration at thecommon gas outlet is between 23 to 25% depending on manufacturer179. @Howdoes the Link-25 proportioning system work?The Link-25 system is found on conventional Datex-Ohmeda machines.The heart of the system is the mechanical integration of the nitrous oxideand oxygen flow control valves. It allows independent adjustment of eithervalve. yet automatically intercedes to maintain a minimum 25% oxygenconcentration with a maximum nitrous oxide-oxygen flow ratio of 3:1.The Link-25 automatically increases oxygen flow to prevent delivery of ahypoxic mixture. A 14-tooth sprocket is attached to the nitrous oxide flowcontrol valve and a 28-tooth sprocket is attached to the oxygen flow controlvalve. A chain physically links the sprockets. When the nitrous oxideflow control valve is turned through two revolutions. or 28 teeth, theoxygen flow control valve will revolve once because of the 2: 1 gear ratio.The final 3:1 flow ratio results because the nitrous oxide flow controlvalve is supplied by approximately 26 psig, whereas the oxygen flow controlvalve is supplied by 14 psig. Thus, the combination of the mechanicaland pneumatic aspects of the system yields the final oxygen concentration.The Link-25 proportioning system can be thought of as a system thatincreases oxygen flow when necessary to prevent delivery of a fresh gasmixture with oxygen concentration ofless than 25%. [Barash, CUn. Anes ..180. @List five (5) conditions that can "fool" the proportion -limiting systemsThe following five situations can lead to delivery of hypoxic gas mixtureson workstations equipped with proportioning systems: (I) wrong supplygas, (2) defective pneumatics or mechanics. (3) leaks downstream, (4)inert gas administration, and (5) dilution of inspired oxygen concentrationby volatile inhaled anesthetics. [Barash, CUn. Anes .. 6th? 2009 pp659181. @What type of gas can lead to delivery of ahypoxic mixture on a workstation equippedwith a proportioning system? What is mandatorywhen such a gas is present?An inert. third gas, such as He. N2 or C02, can cause delivery of a hypoxic mixturebecause contemporary proportioning systems link only nitrous oxide and oxygen.Use of an oxygen analyzer is mandatory (or preferentially a multigas analyzer) ifthe operator uses a third gas. [Barash. Clin. Anes .. 6th? 2009 pp659182. ?What oxygen sources and delivery pressuresare acceptable for transtracheaJ jetventilation? What sources and pressures arelIot adequate [or transtracheal jet ventilation?There are several options for the oxygen source and delivery pressuresused with transtracheal ventilation. If a high·pressure system is availa·ble-for example. a metered and adjustable oxygen source with a hand·controlled valve and a Luer-Iock connector-1S to 30 psi of oxygen (centralhospital supply or regulated cylinder) can be delivered directlythrough the catheter. with insumations of 1 to 1.S seconds at a rate of 12insufflations per minute. If a 16-gauge catheter has been placed, thissystem will deliver a tidal volume of 400 to 700 mL. At a delivered pressureof 50 psi. a 16·guage delivers 500 mL of oxygen per second. III mostinstances, 25 psi is a sufficietlt inspiratory pressure (Nagelhout). Low·pressure systems cannot provide enough flow to expand the chest adequate·ly for oxygenation and ventilation (e.g., Ambu bag, 6 psi; common gasotlt/et, 20 psi). {Barash, Clin. Anes .. 6'h 2009 pp788; Nagelhout, NA. 4,183. ?Consider a ventilator in pressure co ntrolmode: what parameter fluctuates with eachcycle? What patient parameters determine this flucation?In pressure control mode, the ventilator is set so that the inspiratorypressure is greater than the positive end· expiratory pressure. In thismode, tidal volume fluctuates (varies) with alterations in patient pulmonarycompliance, pulmonary res istance, and with patient-ventilator asynchrony184. @>Identifyfour(4) reasons why positivepressure ventilation of 25 cm H20 would notbe sufficient to ventilate an individual.Positive pressure ventilation at 25 cm H20 would not be enough pressureto ventilate if: (1) the upper airway is obstructed, (2) the patient has sufficientmuscle tone to prevent chest expansion, (3) the individual has decreasedpulmonary compliance, or (4) the individual has increased pulmonaryresistance. [Hagberg, Benumofs Airway Management. 2e. 2007185. ,..'What is the suggested protocol to wean apatient from synchronized intermittentmandatory ventilation (SIMV)?To wean a patient from synchronized intermittent mandatory ventilation(SIMV), progressively decrease the number of breaths (by 1-2breaths/minute) as long as the arterial CO2 tension and respiratory rateremain acceptable (generally < 45-50 mm Hg and less than 30 breaths perminute). {Morgan, Mikhail, and Murray. CUn. Anesthesiol.. 4th ed., 2006186. What is the most common site for breathingcircuit disconnection?Although disconnections can occur anywhere in the breathing system, themost common site is between the breathing system and tracheal tubeconnector or heat-moisture exchanger (HME). [Dorsch187. Rank the relative efficiency of Maplesonsystems with respect to prevention of rebreathingduring spontaneous ventilationWith respect to prevention of rebreathing during spontaneous ventilation,the relative efficiency of Mapleson systems is A > DPE > CB. [Miller,Anesthesia. 6e. 2005 pp293; Barash, Clinical Anes .. Se. 2006 pp578-579;188. Rank the relative efficiency of Maplesonsystems with respect to prevention of rebreathingduring controlled ventilation.With respect to prevention of rebreathing during controlled ventilation,the relative efficiency of Mapleson systems is DPE > BC> A. [Miller,Anesthesia. 6e. 2005 pp293; Barash, Clinical189. KYou arc scheduled to provide anesthesiato a patient with a known susceptibility tomalignant hyperlhermia. How wili youprepare the gas machine in anlicipation of this case?The concern in this situation is the presence of trace amounts of volatileagents in Ihe rubber and plastic components of the gas machine and inthe ventilator and CO2 absorber. The following 3 actions should be takento prepare the gas machine for the patient with a known susceptibility tomalignant hyperthermia. (1) The gas machine should be thoroughlyflushed with 100% oxygen for at least IO minutes (0 reIllove residualtraces of volalile agents from rubber and plastic components in the ma chine. (2) The breathing circuits and CO, canister should be replaced. (3)Vaporizers should be drained, inactivated, or removed190. ?When is a nasopharyngeal airway preferableto an oropharyngeal airway?A nasopharyngeal airway (nasal airway, nasal trumpet) is better toleratedthan an oral airway if the patient has intact airway reflexes. A nasal airwayis preferable if the patient's teeth are loose or in poor condition, if there istrauma or pathology of the oral cavity and can be used when the mouth cannot be opened. [191. @)List four (4) contraindications to using anasopharyngeal airway.Contraindications to a nasopharyngeal airway include (1) anticoagulation,(2) basilar skull fracture, (3) pathology, sepsis, or deformity of thenasal cavity or nasopharynx, and (4) a history of nosebleeds requiringmedical treatment. [Dorsch, UAE. Se. 2008 pp4S4]192. @)Howdoyouestimatethecorrectlengthfor a nasopharyngeal airway?The length of a nasal airway can be estimated as the distance from thenares to the meatus (opening) o/the ear. The length should ne 2-4 cmlonger than a corresponding oral airway193. ?What is the purpose of an oral airway?List five (S) uses for an oral airway.Any airway creates an artificial, patent passage to the hypopharynx. Oralairways are used to (1) prevent the patient from biting an oral trachealtube, (2) protect the patient from biting the tongue, (3) facilitate oropharyngealsuctioning, (4) obtain a better mask fit, and (S) provide a pathwayfor inserting devices into the esophagus or pharynx194. @When is an oral airway indicated? Contraindicated?An oral airway is indicated for an obstructed upper airway in an unconsciouspatient and when there is need for a bite block in an unconsciouspatient. An oral airway is contraindicated in the awake or lightly anesthetizedpatient-the patient may cough or develop laryngospasm duringairway insertion iflaryngeal reflexes are intact.195. @)What is the purpose of the laryngoscopeflange?The flange projects off the left side of the laryngoscope and serves tosweep the tongue out of the way and to guide instrumentations along thelaryngoscope blade. [Dorsch, UAE. Se. 2008 ppS24J196. @)What is a lighted intubation stylet andwhen is it useful?A lighted intubation stylet (lightwand, [flexible] lighted stylet, Trachlight",illuminating or lighted intubating or intubation stylet) uses transilluminationof the soft tissues in the anterior neck to guide the tip of thetracheal tube into the trachea or to determine the position of the trachealtube or other airway device. During direct laryngoscopy, the lighted styletcan be used to improve the view in the hypopharynx. The lighted stylet isespecially useful in situations where a fiberscope is unavailable or endoscopyis difficult to perform (e.g .? when an airway is obscured by blood orsecretions or when a patient's head cannot be flexed or extended197. @Into what shape should a lighted intubationstylet ("lightwand") be molded? Whatapproximate angle is the bend of this shape?For oral intubation. a "r or "hockey stick" bend of approximately 75- to 120-degrees just proximal to the cuff is recommended. Care should be taken not tobend the stylet at the point at which the bulb meets the shaft. [Dorsch. UAE. Se.2008 pp609; Barash. Clin. Anes .. 61h? 2009 pp1187; Miller & Stoelting. Basics198. List potential uses for an airway exchange catheter.An airway exchange catheter (guiding catheter, director, stylet catheter.catheter guide. elastic stylet. tracheal tube replacement obturator, tubechanger or exchanger, ventilation or exchange bougie, jet-style catheter.jet stylet, intubation catheter. intubating introducer) can be used for anumber of purposes including: tracheal tube or supraglottic device exchange,replacing and existing tube, changing a tracheal tube from oral tonasal, intubation. extubation. to provide ventilation during microlaryngealsurgery. to provide a useful guide to the trachea during flexible endoscopy.and facilitating passage of a tracheal tube over a fiberscope.199. @Whatfeaturesareadvantageous for anairway exchange catheter? What do thesefeatures afford during extubation?Airway exchange catheters have a central lumen. and rounded. atraumaticends. The catheters are graduated from the distal end. The proximalend is fitted with either a IS-mm or a Luer-Iock Rapi-Fit adapter, whichcan be quickly removed and replaced for ETT removal or exchange. Withthese adapters an oxygen source can be used to provide insumated or jetventilatedoxygen if the patient fails extubation and/or if reintubationover the catheter fails. [Barash. Clin. Anes .. 6th? 2009 pp771]200. What is an Eschmann introducer?The Eschmann introducer is a 60-cm. stylet-like device that has a S-mmexternal diameter and a 3S-degree bend 2.5 cm from the end that is insertedinto the trachea. Its structure is designed to provide a combinationof stiffness and flexibility. It is more commonly known as the gum elasticbougie. (although it is not gum. elastic. or a bougie. according to Miller!).It is an extremely useful instrument when laryngoscopic view is poor orthe tube cannot be otherwise guided into the glottis. It is also useful inlimiting the degree of necessary neck movement during intubation withpotential cervical spine injuries and to lesse~ the risk of dental damage.The introducer can be manipulated under the epiglottiS. its angled segmentdirected anteriorly toward the larynx. Once it has entered the larynxand trachea. a distinctive" clicking" feel is elicited as the tip passes overthe cartilaginous structures. [Miller. Anesthesia. 6e. 2005 pp1632; B201. @Inspiratory pressure should be limited towhat value when providing positivepressureventilation by a manual resuscitator(bag-valve mask, for example)?When providing positive-pressure ventilation with a manual resuscitator.such as a bag-valve mask. it is imperative to limit the pos~tive pressure to25 cm H20 to avoid inflating the stomach. which increases the risk ofregurgitation. [Hagberg. Benumofs Airway Management. 2e. 2007 pp36S202. What is the most common complicationto a patient being jet ventilated?Tracheal mucosal damage and thickened secretions blocking the airways,which result from inadequate humidification of the delivered gas, remainsa major problem during high frequency jet ventilation203. @Ust four (4) indications for electroencephalographicmonitoring during anesthesia.Four ind ications for EEG monitoring during anesthes ia are: (1) ca rotidendarterectomy (perfusion jeopardized during cross-clamping of thecaro tid artery), (2) cardiopulmonary bypass procedures, (3) cerebrovasclilarsurgery, for example, temporary clipping during aneurysm surgeryor vascular bypass procedures, and (4) when burst suppression is des ir irablefor ce rebral protec tion204. @)List two (2) ind ications for electroencephalographicmonitoring in the intensive care unit.In the intensive care unit, EEG monitoring is indicated (I) for barbituratecoma for patients with traumatic brain injury, and (2) when subclinicalse izu res are suspected. IBarash, Ciill. Alles .. 6'" 2009 pp I 0091205. ?Electroencephalogram (EEG) waves arecategorized as alpha, beta, delta, and theta,based upon frequency and amplitude. Givethe frequency range (in Hz) of each of theseEEG waveforms and the brain region{s)from which each is recorded.Delta waves are the lowest frequency (0-4 Hz), greatest amplitude wavesin the electroencephalogram (EEG). Theta waves range from 4 to 7 Hzand exhibit a slightly lower amplitude than delta waves. Alpha waves aretypically recorded over the posterior aspect of the head during awake,alert, but relaxed activities. Alpha waves have an intermediate amplitude-less than delta and theta, but greater than beta waves-and a frequencyrange of8-12 Hz. Finally, beta waves are the highest frequency (>12 Hz), lowest amplitude waveforms and are recorded predominantlyover the frontal areas of the head, but can be seen from all brain regions206. ?Briefly describe the typical brain activitiesassociated with each electroencephalogram(EEG) waveform. Reminder: the waveformsare delta, theta, alpha, and beta.Delta waves (0-4 Hz) are seen in the sleeping adult, but are consideredabnormal in the awake adult. Delta waves are also seen in encephalopathy,deep coma, and deep anesthesia. Theta waves (4-7 Hz) are seen insleep and in deep anesthesia. Prominent alpha wave activity is characteristicof awake, alert, but relaxed activities. An "eyes closed" resting alphapattern is the baseline awake pattern used when anesthetic effects on theEEG are described. Beta waves (> 12 Hz) are characteristic of aroused,attentive, active thinking. [Nagelhout, NA. 41h. 2009 pp350; Barash207. ?What happens to the electroencephalography(EEG) waveforms as anesthetic depth increases?Increasing depth of anesthesia from the awake state is characterized byincreased amplitude and synchrony in the EEG waveforms208. ? As anesthetic depth increases, periods ofelectrical silence occupy greater proportionsof the electroencephalogram (EEG). Give asynonym for "electric silence" in the EEG.A period of electrical silence in an EEG is called an isoelectric EEG pattern.208. ?What MAC correlates with an isoelectric EEG pattern?An isoelectric pattern dominates the EEG in the range of 1.5 to 2.0 MAC209. ?During certain surgical procedures, maximalsuppression of cerebral metabolic rateis desirable to protect the brain during anischemic insult. Under such circumstances,the anesthetic agent can be titrated againstthe EEG until the desired effect is achieved.Typically, instead of an isoelectric EEG, thegoal is a state called burst suppression. Characterize"burst suppression" on the electroencephalogram (EEG)Electroencephalogram (EEG) burst suppression is characterized by periodsof isoelectric EEG punctuated by "bursts" of EEG activity. The"burst" is high-frequency activity and the "suppression" is 0.5- to severalsecondperiods ofisoelectric activity210. @>The electroencephalogram (EEG) is occasionallyused during cerebrovascular surgeryto confirm adequate cerebral oxygenation.Identify four conditions or agents that canproduce EEG changes mimicking cerebral ischemiaThe electroencephalogram (EEG) changes that accompany cerebralischemia can be mimicked by (I) hypothermia, (2) electrolyte disturbances,(3) marked hypocapnia, and (4) anesthetic agents211. @)Which intravenous anesthetic agents haveminimal effect on evoked potentials and arethus compatible with effective monitoring of evoked potentials?Barbiturates. propofol. and fentanyl/or remifentanil have less of an effecton cortical evoked potentials and are thus compatible with effective monitoringof somatosensory evoked potentials (SSEP) and brainstem auditoryevoked potentials (BAEP). [Dunn.212. What agents will not alter bispectral index(BIS) monitoring?Since the bispectral index (B1S) is based upon the hypnotic action ofagents. the BIS is flot affected by opioicls or analgesics. Nitrous oxidealone will have no effect on SIS. Ketaminc has minimal effect on BIS, andmay slightly increase BIS transiently.IDunn, ct al., Clin. Anes. Proceduresof the Massachusetts General Hospital213 You are considering in sertion of a centralvenous line via the left internal jugular vei n;what are three risks of using the left jugular vein for cent ral line insertion?Left-sided ca theterization via the left jugular vein increases the risk of (I)vascular erosion, (2) pleural effusions, and (3) pUlleture of the thoracicdllct.leading to chylothorax. [Morgan. Mi214. Think about a central venous pressure(CVP) waveform: you know what the a, cand v waves represent. What do the x descentand y-descent indicate?On the central venous pressure (CVP) waveform. the x-descent occursduring ventricular systole and represents atrial relaxation with downwarddisplacement of the tricuspid valve. The y-descent occurs during diastoleand represent early ventricular filling through the open tricuspid valve.215. ?Give three (3) contraindications to use ofa pulmonary artery catheterRelative contraindications to pulmonary artery catheterization are (1)complete left bundle branch block, (2) Wolff-Parkinson-White syndrome,and (3) Ebstein's malformation.216. ?Where could a central venous or pulmonaryartery catheter be inserted in the patientwith superior vena cava syndrome?The edema due to superior vena cava syndrome often times necess itatesvenous access through the lower extremity. A central venous or pulmonaryartery catheter can be inserted through the femoral vein in suchcases. [Hines. Stoeltillg's Co-existillg. 5e. 2008 pp 184}217. What three (3) valuable ca rdiovascularparameters are obtained from an arterialline?Invasive arterial blood pressure monitoring provides information regarding(I) left ventricu lar volume. (2) left ventricular function. and (3) systemicvascular resistan ce. [Nagelhout & Zaglaniczny, NA. 3rd ed., 2004,p321218. What condition or situations result in anabnormal arterial waveform with a falseelevation of systolic pressure?A decreased arterial compliance or a decreased transducer system frequency(ringing or overshoot) produce distortion of the arterial waveform.This particular distortion produces extra waveforms and results inoverestimation of systolic blood pressure219. What factors may cause damping of thearterial pressure transducer system? Whateffect does system damping have on arterial blood pressure readings?Damping refers to how quickly a system comes to rest after being set inmotion. The presence of air bubbles in the tubing, thrombus formation inthe catheter, or inadvertent kinking of the catheter may overly damp thesystem. Losses of the dicrotic notch and fine details in the waveformindicate an overly damped system. Overdamping results in an underestimationof systolic blood pressure and an overestimation of diastolic pressure;MAP remains fairly accurate. [Nagelhout220. Your patient requires arterial cannulation:list 6 arterial cannulation sites, in order of preference.Multiple arteries can be used for direct measurement of blood pressure;the top 6 sites for arterial cannulation are: (1) radial artery, (2) ulnarartery, (3) brachial artery, (4) axillary artery, (5) femoral artery, and (6)dorsalis pedis artery. (Note: Morgan, et al. place221. For each of the 6 arteries listed in theprevious question, list a clinical point ofrelevance or interest.(1) Radial artery: the most commonly selected site for arterial cannulation;non-tapered catheters are preferred for cannulation of the radialartery. (2) Ulnar artery: more difficult to cannulate owing to its deeperand more tortuous course; the ulnar artery is the primary arterial supplyof hand blood flow. (3) Brachial artery: large'and easily identifiable in theantecubital fossa; insertion site is medial to biceps tendon; can accommodatean IS gauge needle; median nerve damage is possible. (4) Axillaryartery: the insertion site is at the junction of the pectoral and deltoidmuscles-special kits are now available; nerve damage can result fromhematoma or traumatic cannulation. (5) Femoral artery: provides easyaccess in low flow state; the femoral artery is prone to pseudoaneurysmand formation of atheroma, and there is potential for retroperitonealhemorrhage. (6) Dorsalis pedis artery: being the farthest distance fromthe aorta, arterial waveforms are most distorted, leading to higher systolicpressure estimates. [Barash, Clin. Anes., 5th ed., 2006, p675t; Morgan,Mikhail, and Murray, Clin. Anesthesiol., 4th ed., 2006, ppI23-125; Stoelting& Miller, Basics, 5th ed., 2007, p30St]222. What two hemoglobin alterations willyield falsely high pulse oximeter readings?Carboxyhemoglobin (carbon monoxide poisoning) will cause falsely highpulse oximeter readings. Carboxyhemoglobin and oxyhemoglobin absorblight at 660 nm identically, thus the falsely high reading. Methemoglobinhas the same absorption coefficient at both red and infrared wavelengths;the resulting 1:1 ratio corresponds to a saturation reading of85% -thepulse oximeter is essentially "locked" at 85% by the presence of methemoglobin.Thus, ijS.02 is actually less than 85%, the reading will be falselyhigh. [Morgan, Mikhail, and Murray223. What is the best monitor to detect a disconnection?According to Stoelting and Miller, capnography and spirometry have thehighest value in detecting disconnection. The next best monitors fordetecting disconnection are pulse oximetry and the stethoscope224. ?Ust seven characteristics of nondepolarizingneuromuscular blockadeSeven characterist ics of nondepolarizing NM blockade are: (I) Decreasedlwilch heighl, (2) fade during letany, (3) fade during lrain-of-four (Tl:T4ral io >0.7), (4) posl-lelanic pOlenlialion, (5) absence of fasciculalions, (6)antago nism of block by acetylcholineste rase inhibitors, and (7) augmentalionof block by olher non depolarizing agents. IBarash225. Describe the basic operation of a forced air warmerA forced-air warmer (such as the Bair Hugger-, Arizant Healthcare) entrainsambient air through a microbial filter. The air is warmed using anthermostat-controlled electric heater, and then blown through a hose thatis connected to an inflatable patient cover. Forced-air warmers are alsoknown as convec tion warming devices and warm air blowers. IDorsch226. List 2 standard for forced-air warmingdevices.The u.s. standards ror forced -air warming devices (2002) are (I) themaximum contact surface temperature shall not exceed 48°C, and (2) theaverage contact surface temperature shall not exceed 46°C during normal conditions227. State advantages afforded by forced-airForced-air warming is safe, simple effec tive. and inexpensive. There are avariety of ava ilable covers, both disposable and reusable, as well as pediatricstyles. Forced·air warm ing provides more calories-to-cost than otherwarming modalities. Fibcropt ic laryngoscopes can be warmed before usewi th a forced-air device. The forced-a ir warmer can be used to warm theoperating table before the patient is transferred to the table. It can also beused for cooling. Finally, fo rced-air wa rmers have been used to relieve claustrophia228. List some disadvantages of forced-air warmers.Electric power requirements of forced-air warmers make them unsuitable for fielduse. They arc cumbersome 10 transfer or set up in a CT scanner. The forced-airwarmer must occaSionally be removed from the pat ient to expose covered areas.Finally. many systems do not permit the concurrent use of multiple blankets (Le.,upper and lower body) without using two separate fo rced-air units_ [Dorsch, UAE229. Define perioperative blood salvage.Perioperative blood salvage refers to the recovery of shed blood from thesurgical field or wound drains and readministration to the patient. Inmost instances, the process involves "washing" of the salvaged materialwith return of only the RBC component of blood. [Barash230. List seven situations in which intraoperativeblood salvage (IBS) may be employed.Seven situations in which intraoperative blood salvage (IBS) is commonlyemployed are: (l) cardiovascular surgical procedures, (2) aortic reconstruction,(3) spinal instrumentation, (4) joint arthroplasty, (S) livertransplantation, (6) resection of arteriovenous malformations, and (7)occasionally in the management of trauma patient231. Briefly describe the operation of contemporary"cell saver" (blood salvage) devices.What is the hematocrit range of the salvagedblood aliquots returned to the patient? Howefficient is the modern cell saver?Contemporary "cell saver" devices anticoagulate the salvaged blood as itleaves the surgical field, separate the RBCs from other liquid and cellularelements by centrifugation, and then wash the salvaged RBCs extensivelywith saline. The RBCs are typically returned to the patient suspended insaline in aliquots of 12S or 22S mL with a hematocrit of 4S to 6S%. ApproximatelySO% of RBCs are salvaged, therefore anticipate administration of allogenic blood232. What are the contraindications to intraoperativeblood salvage?Contraindications to intraoperative blood salvage are the presence ofinfection, malignant cells, urine, bowel contents, or amniotic fluid in theoperative field. [Barash, Clinical Anes .. Se. 2006 pp21S233. ~[dentify expected complications of intraoperativeblood salvage.The potential complications of intraoperative blood salvage (IBS) are afunction of the reinfusion of materials that might remain after the washingprocess. Such materials that escape from the washing process includefat, microaggregates such as platelets and leukocytes, air, red cell stroma,free hemoglobin, heparin, bacteria, and debris from the surgical field.Most of these are in fact removed quite efficiently by contemporary cellsalvage equipment. Bacteria are the exception and contamination of cellsaver return with skin organisms is relatively common234. What coagulopathy is expected afterintraoperative blood salvage? How wouldyou manage this coagulopathy?DHutional coagulopatby is to be expected after intraoperative bloodsalvage because the washing process removes essentially all clotting factorsand most platelets. Management is the same as for a dilutional coagulopathyoccurring with administration of homologous or preoperativeautologous donation (PAD) blood. [Barash, Clin235. Briefly describe the basic operation of aheat and moisture exchanger (HME).A heat and moisture exchanger (HME) conserves some exhaled water andheat and returns them to the patient in the inspired gas. Many HMEs alsoperform bacterial/viral fIltration to prevent inhalation of small particles.The HME is also known as a condenser humidifier, Swedish nose (I),artificial nose, nose humidifier, passive humidifier, regenerative humidifier,moisture exchanger, and vapor condenser. [236. What are the indications for heat andmoisture exchanger (HME) use?An heat and moisture exchanger (HME) can be used to increase inspiredheat and humidity during both shorL- and long-term ventilation. HMEsare indicated if the patient is hypothermic and for use in the neonatalcircuit. HMEs may be especially useful in transporting the intubatedpatients. IDorsch, UAE. 5e. 2008 pp299237. List two contraindications to heat andmoisture exchanger (HME) usc. Heat and moisture exchangers are contraindicated in (1) patients withthick and copious, or bloody secretions, and (2) patients with a leak thalprevents exhaled gas from pass ing through the HME (e.g., bronchopleuralfistula, or leaking tracheal tube cuff). 238. fList 5 adull patients who are inappropriatecandidates for ambulatory (ou tpatient)surgery.The following 5 adult patients are inappropriate candidates for ambulatory(ou tpa tient) surgery: (I ) patients expected to have major blood loss orundergoing major surgery; (2) ASA III and IV patie nts who require complexor ex tended monitoring or pos topera tive treatment; (3) morbidlyobese pa tients with significant respiratory disease. including sleep apnea;(4) patien ts with a need for complex pain management; and, (5) patientswith significant fever, wheezing, nasal congestion, cough, or other symptomsof a recent upper resp ira tory inrection. IDunn, et aI., Clin. Atles.Procedures of the Massachusetts General Hospital, 7" ed., 2007, p5631239. List 6 other adull patients who are inappropriatecandidates for ambulatory (ou lpa· tient) surgery.The following 6 addi tional patients are not appropriate candidates forambulatory (ou tpatient) surgery: (I) patients susceptible to malignanthyperthermia; (2) patients with uncontrolled se izure activity; (3) patientswith acute subs tance abuse; (4) patients wi th active in fection; (5) uncooperativeor unreliable patients; and, (6) pat ients who have no responsibleadult at home duri ng convalescence240. Which two crystalloid solutions contain potass ium (K')? The two crys talloid solutions that con tain potassium (K') are isotoniclactated Ringers (LR) and hype rtonic D5LR241. Banked blood may go through manychanges before it is infused into the patient.What factors are absent in banked blood?Blanked blood is devoid of platelets, factors V and VIII, and 2,3-DPG.[Nagelhout & Zaglaniczny, NA, 3rd ed., 2004242. @Wh.t blood product "should" be ABOcompatible, but is not strictly mandatory?Platelets bear both ABO and HLA (human leukocyte antigen) and thereforeABO compatibility is ideal because incompatibil ity shortens theli fespan of the plateiet. However, plateiet ABO compatibil ity is not re quired.243. Describe the current treatment of dilutiona!coagulopathy.Dilution.1 coagulopathy usually becomes a problem during massivetransfusions. Both platelets and coagulation factors are markedly decreasedand must be replaced. They should be administered after laboratory documentation of tire deficiency. It is no longer accepted practice togive fresh rrozen plasma (FFP) routinely after 5 units of packed red bloodcell (PRBC), and it is not proper to give platelets after 10 units ofPRBC.At present, dilutional coagulopathies appear to be rare, even with thetransfusion or one blood volume. [Yao244. @Ifan acute hemolytic reaction is suspected,the blood bank should be notified.Blood and urine samples should be sent tothe laboratory for examination. What twoimmediate tests will be performed on thespecimens?Immediate tests on the posttransfusion specimen will include (1) a visualcheck for hemoglobinemia and (2) a direct antiglobulin (Coombs) test.The direct antiglobulin test examines recipient RBCs for the presence ofsurface immunoglobulins and complemenllf positive, an acute hemolyticreaction may have occurred and additional testing is indicated to ascertainthe cause, including repeat ABO/Rh type, antibody screen, crossmatching,and other tests as indicated. The blood bank will determinewhether the unit of blood had been correctly released to the patient. [Barash,Clin. Anes .. 6th? 2009 pp373; Miller, Miller's Anesthesia, 7th?245. @)Consider the patient in the lateral decubitusposition with no axillary roll and a pulseoximeter on the dependent hand. What isthe most likely cause for an apparently low S&02 from the pulse oximeter?The axillary neurovascular bundle is compressed, compromising bloodflow to the extremity. A small support placed just caudad of the downsideaxilla can be used to lift the thorax enough to relieve pressure on theaxillary neurovascular bundle and prevent disturbed blood flow to thearm and hand. This chest support (inappropriately called an axillary rollby some) should support only the chest wall and it should be periodicallyobserved to ensure that it does not impinge on the neurovascular structuresof the axilla. [Barash, Clin. Anes .. 6th? 2009 pp802]246. KWhat nerves may be damaged during face mask ventilation?The buccal branch of the facial neTve (CN VII) and the supraorbital branch of the ITigemillalll erve (CN V)247. In the lateral position, injuries to whatnerves are most likely? Why?The common peroneal (fibular) nerve is the most commonly injurednerve of the lower extremity when the patient is in the lateral position.The injury results from compression of the common peroneal (fibular)nerve between the OR table and the head of the fibula. To prevent com·mon peroneal nerve injury in the lateral position, padding extending fromthe knee to the heel should be placed along the lateral aspect of the de·pendent leg. Injury to brachial plexus because of improper padding of thechest and head is possible. [Nagelhout & Zaglaniczny, NA. 3e. 2005pp401; Barash, Clinical Anes .. Se. 2006 pp6S4248. "'-Describe the use and operation of the fracture tableThe orthopedic fracture table consists of a body section to support thehead and thorax, a sacral plate for the pelvis with a perineal post, andadjustable footplates. The most important features of the table are theability to maintain traction on a lower extremity and to obtain surgicaland fluoroscopic access. Because the patients requiring this table are oftenin pain, anesthesia is usually induced before the patient is moved to thetable. The supine patient who is placed on a fracture table for repair of afractured femur usually has the pelvis retained in place by a vertical poleat the perineum, with the foot of the injured extremity fIXed to a mobilerest. A worm gear on the rest lengthens the distance between the foot andthe pelvis so that the bone fragments can be distracted and realigned.[Miller, Anesthesia. 6e. 2005 pp1163; Barash, Clinical Anes .. Se. 2006249. ,..-The patient is positioned on a fracturetable; what nerve injuries are possible?Unless the pole is well padded, severe pressure can be exerted on thepelvis, and damage can occur to the genitalia and the pudendal plete loss of penile sensation has been reported after use of the fracturetable. The correct position for the pole is against the pelvis betweenthe genitalia and the uninjured limb. Other possible nerve injuries on thefracture table include brachial plexus damage (due to extended arm orarm placed directly across the chest) or lower extremity compartmentsyndrome. [Barash, Clinical Anes .. Se. 2006 pp6S2, 1119-1120; Miller250. @)What is compartment syndrome? Whatfeatures characterize compartment syndrome?Compartment syndrome is a potentially life-threatening position-relatedcomplication that causes damage to neural and vascular structures fromswelling of tissues within a muscular compartment, especially those of theleg. If perfusion to an extremity is inadequate, a compartment syndromemay develop. Compartment syndrome is characterized by ischemia,hypoxic edema, elevated tissue pressure within fascial compartments, andextensive rhabdomyolysis. [Nagelhout, NA. 4th. 2009 pp427251. @)How can compartment syndrome in theleg be precipitated?Compartment syndrome can be precipitated by intraoperative hypotensionin conjunction with leg elevation that causes low-flow states. Pneumaticcompression boots and fluid extravasation into tissues have beenlinked to compartment syndromes. Vascular obstruction of major legvessels by intrapelvic retractors, by excessive flexion of knees or hips, orby undue popliteal pressure from a knee crutch may cause compartmentsyndrome. External compression of the elevated extremity by straps or legwrappings that are too tight, by the inadvertent pressure of the arm of asurgical assistant, or by the weight of the extremity against a poorly supportiveleg holder may also precipitate compartment syndrome252. ?What is the definitive treatment for compartmentsyndrome? What sequelae willensue if compartment syndrome is not treatedThe definitive treatment for compartment syndrome is fasciotomy. Ifuntreated, compartment syndrome will progress to tissue necrosis withmyoglobinuria and acute renal failure (crush syndrome). Amputation and even death may occur253. @State five (5) risk factor for difficult maskventilation, from greatest risk to leas l.Five risk factors for difficult mask ventilation, from greatest to least riskare: (I) presence of a beard. (2) body mass index >26 kg/m'. (3) lack ofteetll (edentulous). (4) age > 55 years. and (5) history of snoring254. What is the pressure limit for positivepressureface mask ventilation?Positive-pressure ventilat ion via a face mask should nomlally be limitedto 20 em !-hO to avoid stomach inflation255. List the guidelines to be followed in orderto use a laryngeal mask airway (LMA) duringa laparoscopic procedure.The follOWing guidelines are recommended for use of the laryngeal maskairway (LMA) during laparoscopy: (1) the clinician should be an experiencedLMA user; (2) careful patient selection is required (e.g., fasted,not obese); (3) use correct size LMA; (4) tell the surgeon you are using anLMA; (5) use a total IV anesthetic technique or volatile agent; (6) adhereto the "IS" rule: <15 degrees tilt, <15 em H20 intra-abdominal pressure, < 15 minutes duration; (7) avoid inadequate anesthesia during su rgery;and, (8) avoid disturbing the patien t during emergence.INagelhout &Zaglaniczny, NA. 3e. 2005256. @Youdecidealaryngeal mask ai rway(LMA) is app ropriate for the ainvay managementof the 9-kg patient, but a 1.5 LMAis not available; will you use a size I or a size 2 LMALMA size selection is critical to its successful use, and to the avoidance ofminor as well as more significant complications. The manufacturer recommendsthal the clinician choose the lurgest size that will fit com/ortablyin the oral cavity, and then inflate to the minimum pressure that allowsventilation to 20 em H20 without an air leak. Accordingly. a size 2LMA classic is appropriate for the 9-kg patient (Morgan, et al. 6.5-20kg .. size 2 LMA).IBarash, c/in. Alles .. 6,h 200257. @What is the Murphy eye on a trachealtube? What is the purpose of the Murphyeye?A Murphy eye is a hole through tl,e tracheal tube wall opposite to thebevel. The purpose of the Murphy eye is to provide an alternate pathwayfor gas flow if the bevel becomes occluded. IDorsch258. @What is the name for tracheal tubes that lack a murphy eye?Tracheal tubes that lack a Murphy eye are called Magill-type tubes. Anadvantage of the Magill-type tube is that the cuff can be placed closer to the tip of the tube259. ?What does the ASTM require of trachealtubes?The ASTM requires that a radio-opaque marker is placed at the patientend of the tube or along the entire length of the tube to determine theposition of the tube after intubation. [Dorsch, UAE. Se. 2008 ppS64260. How will the PaC02 change during thefirst minute of low-flow apneic ventilation(apneic insufflation)? During each minute after the first minute?During low-flow apneic ventilation (apneic insuffiation), the PaC02 risesapproximately 6 mm·Hg during the first minute, and approximately 3-4mm-Hg each minute thereafter. By extension, during apnea-from anycause-PaC02 wi ll rise by 6 mm-Hg during the first minute, and 3-4mOl-rig each minute thereafter.IMiller, Allesthesia. 6e. 2005 pp1901261. @>What is Klippel-Fell syndrome? Whatother problems are associated with KlippelFell syndrome?Klippel-Feil syndrome is a musculoskeletal disorder characterized by ashort neck owing to a reduced number of cervical vertebrae, or fusion ofseveral vertebrae. Movement of the neck is severely limited. Spinal stenosisand kyphoscoliosis are associated with Klippel-Fell and mandibularmalformations andlor micrognathia may be present. Taken together, thepatient with Klippel-Fell presents as a difficult airway. [Hines, Stoeltin262. vWhat is Ludwig's angina? What are thesigns and symptoms of Ludwig's angina?Ludwig's angina is an overwhelming generalized septic cellulitis of thesubmandibular region. Ludwig's angina generally occurs after dentalextraction; early signs and symptoms include chills, fever, drooling ofsaliva, inability to open the mouth, and difficulty in speaking, as well asedema of the tongue, neck, and submandibular region. The cause is oftenhemolytic streptococci, but may be a mixture of aerobic and anaerobicorganisms. [Barash, Clin. Anes., Slh ed., 2006, P 1009; Stoelting & Dierdorf,Anesthesia and Coexisting Diseases263. vDescribe airway management for thepatient with Ludwig's angina.Airway management in the patient with Ludwig's angina may be extremelydifficult. Preliminary tracheostomy using local anesthesia in the awakepatient is the safest course. Other options-depending upon the patient'scondition and ability to cooperate-include an awake fiberoptic intubationwith an armored tube, or an inhalation induction, preserving spontaneousrespiration, followed by intubation with direct laryngoscopy orfiberoptic assistance. [Barash, Clin. Anes., Slh ed., 2006264. ?What two amide local anesthetics and one anestheesterlocal anesthetic are most often used for infiltration anesthesia?The two amide local anesthetics most often used for infiltration anesthe sia are lidocaine (0.5% to 1.0%) and bupivacaine (0.125% and 0.25%)., ester is procaine 0.5%-1%265. ,?'The mechanism(s) of differential block ofsensory and motor nerve fibers by localanesthetics is a controversial topic, at best.State the clinical progression of fiber blockand list 6 mechanisms that contribute to thedifferential block produced by local anestheticsThe clinical progression of differential nerve block by local anesthetics,from first blocked to last blocked, is autonomic fibers, sensory fibers andmotor fibers. At least 6 factors contribute to differential nerve block bylocal anesthetics: (I) the anatomic and geometric arrangement of theindividual fibers in a nerve bundle; (2) the size (diameter) of the individualnerve fibers; (3) the inherent impulse activity (firing rate, frequency) ofthe individual nerve fibers; (4) the variability in longitudinal spread ofagent along the nerve fibers; (5) the effects on ion channels other than thesodium channel, and (6) the choice oflocal anesthetic. Sensory nervefibers fire more often than motor fiber and this may explain to a largeextent why sensory fibers are blocked before motor nerve fibers (Nagelhout).[Stoelting & Miller, Basics, 5th ed., 2007266. vWhat two nerves are derived from theposterior cord of the brachial plexus?The posterior cord of the brachial plexus gives rise La the axillary andradial nerves. [Cousins & Bridenbaugh267. vWhat two nerves are derived from thelateral cord of the brachial plexus?The lateral cord of the brachial plexus gives rise to the musculocutaneousand med ian nerves.267. N'What two nerves are de rived from themedial cord of the brachial plexus?The medial cord of the brachial plexus gives rise to the median and ulnarnerves. [Cousins & Bridenbaugh, Nellral268. v'Describe the landmarks and relativeneedle location in order to perform a mediannerve block at the wrist.In order to perform a median nerve block at the wrist, a 22-gauge needleis directed just medial to the ulnar artery pulse, or, if the ulnar pulse is notpalpable, just medial to the flexor carpi radialis. A total volume of 3 to 5mL of anesthetic is injected to block the median nerve269. N'Which segment of the brachial plexus istargeted in the interscalene approach to abrachial plexus block? (Hint: branches,roots, cords, trunks, divisions ... )The interscalene approach to a brachial plexus block targets the trunks ofthe brachial plexus. After the roots emerge from cervical and thoracicvertebrae (C5-TI), the trunks are sandwiched between the anterior andmiddle scalene muscles. Two sheathes of fibrous tissue enclose the trunksbetween the scalene muscles, forming the space into which local anestheticscan be injected to produce brachial plexus block. Mnemonic: RobertTaylor Drinks Cold Beer (Roots, Trunks, Division, Cords, Branches, inorder from vertebral origins to upper extremity terminations). [Ellis &Feldman, Anatomy for Anaesthetists. 8e. 2004270. 'Your patient requires hand surgery:which upper extremity block would not be appropriate?The interscalene block is suitable for shoulder and arm surgery, but notfor hand surgery. A supraclavicular, infraclavicular, axillary, or Bier blockmay be used for hand surgery. [Morgan, Mikhail, and Murray, Clin. Anesthesiol271. @>What nerve can be blocked in a popliteal fossa block?The sciatic nerve can be localized in the upper area of the popliteal fossa.The goal is to block the sciatic nerve can be blocked before it branchesinto the tibial and peroneal nerves. [Cousins, Neural272. @>List the indications for a popliteal fossablock.A popliteal fossa block is used for foot and ankle surgery, short saphenousvein stripping, and in the pediatric population. The popliteal block providesimproved calf tourniquet tolerance and an immobile foot, comparedto an ankle block. [Cousins, Neural Blockade. 4th. 2009 pp361; Barash,273. Of the 5 sensory nerves to the ankle andfoot, which 3 lie most superficial?The most superficial sensory nerves that supply sensation to the foot arethe superficial peroneal, saphenous, and sural nerves. Mnemonic: allsuperficial sensory nerves to the foot start with "S." [Morgan274. With one exception, all sensory nerves tothe foot arise from the sciatic system-namethe sensory nerve to the foot that does notarise from the sciatic nerve.The saphenous nerve is a terminal branch of the femoral nerve and theonly innervation of the foot not a part of the sciatic system275. 'List two indications for a facial nerve (CNVII) block.Two indications for a facial nerve (CN VII) block are to relieve spasticcontraction of facial muscles, and to treat herpes zoster involvement ofthe facial nerve. [Morgan. Mikhail. and Murray. Clin. Anesthesiol., 4th276. N'What is the occurrence rate of headachesfollowing unintentional dural puncture withan IS-gauge epidural needle while attemptingan epidural anesthetic in the pregnant patient?When a 17- or IS-gauge epidural needle results in unintentional duralpuncture in the obstetric patient, the subsequent incidence of postduralpuncture headache is as great as 70% to SO%. [277. You perform a successful epidural bloodpatch according to standard policy. Howlong should the patient rest and in which position before ambulating?Following a successful epidural blood patch, the patient should rest in thesupine position for 30-60 minutes (up to 2 hours, according to Yao).[Nagelhout & Zaglaniczny, NA, 3rd ed., 2004, pl000; Yao & Artusio, Yao& Artusio's Anesthesiology: Problem-Oriented Patient Management, 5th278. Describe the onset and patient's descriptionof tourniquet pain. Which nerve fiber(s) mediate(s) tourniquet pain?Approximately 45 minutes after the pneumatic tourniquet is inflated, thepatient may complain of dull, aching pain or become restless, even thoughadequate analgesia exists for the operation itself. Tourniquet pain usuallybecomes more intense with time. The current explanation for tourniquetpain genesis involves pain transmission through both A delta and C fibers,and its modulation in the dorsal horn synapses. The C fibers recoverfaster as the block wanes, therefore the C fibers may be dominate. Thedefinitive treatment for tourniquet pain is release of the tourniquet. [Barash279. ?What agent is the most reliable to elicitdeliberate hypotension?According to Nagelhout, sodium nitroprusside is the most reliable, potentagent producing rapid onset of hypotension. [280. List 3 general types of problems that maydelay awakening during post anesthes ia recoveryThe most common causes of delayed awakening in postanesthesia recoveryare: (I) prolonged action of anesthetic drugs (most common). (2)metabolic causes. and (3) neurologic injury (ra re). INagelhout & Zaglaniczny.NA. 3rd ed .. 2004. p1149; Stoelting & Miller281.List 3 metabolic disturbances that maydelay awakening during pos tanesthesiarecovery.Metabolic causes of delayed awakening include hypoglycemia. hyperglycernia,and electrolyte disturbances. spec ifically disturbances of sodium.potassium. and calcium. homeos tasis.282. @l Identifythe two most common causes ofhypoxem ia in the PACU. Which is the mostcommon cause of hypoxem ia in the PACU?Hypoxemia in the PACU is usually caused by hypoventilation. increasedright -to-left in trapulmonary shunting, or both. Increased intrapu lmonaryshunting from a decreased functional res idual capaci ty (FRC) relat ive toclosing capacity is the most commOll cause of hypoxemia following generalanesthesia. The loss of lung volume is often attributed to microatelectasis.A semiupright pos ition helps mainta in FRC283. @What are the two most common reasonsfor delayed discharge from the ambulatory or office-based surgery facility?Excessive postoperative pain and emetic symptoms are the most commoncauses of delayed discharge from ambulatory surgical facilities and canlead to unexpected hospital admissions284. @>List eleven complications of mediastinoscopy.(1) Hemorrhage. (2) pneumothorax, (3) recurrent laryngeal nerve injury.(4) airway obstruction, (5) compression of the innominate artery. (6)chylothorax. (7) air embolism. (8) tension pneumomediastinum, (9)hemithorax. (IO) phrenic nerve injury. and (II) esophageal injury. [Miller.Miller's Anesthesia. 7th? 2009 pp1855; Barash285. @>List the three most frequently encounteredcomplications of mediastinoscopy, onorder of greatest to least incidenceThe most common complication of mediastinoscopy is hemorrhage becauseof the proximity of the vessels and the vascularity of certain tumors.The second most common complication of mediastinoscopy is pneumothorax.usually right-sided. The third most common complication isrecurrent laryngeal nerve injury. and is permanent in up to 50% of cases286. @)Identifythesignsofsuperiorvenacava syndromeSuperior vena cava syndrome is due to increased venous pressure, leadingto (1) dilation of collateral veins in the thorax and neck, (2) edema andcyanosis of the face, neck, and upper chest, (3) edema of the conjunctiva,and (4) evidence ofincreased intracranial pressure including headacheand altered mental status. [Hines, Stoelting's Co-existing. 5e. 2008 pp183287. Identify the 2 greatest risk factors predictiveof morbidity in the patient undergoing acarotid endarterectomy.The two greatest risk factors for morbidity in the patient undergoingcarotid endarterectomy are cigarette smoking and hypertension-bothrisk. factors occur at a 62% incidence rate. [Nagelhout & Zaglaniczny. NA288. In preparation for aortic or carotid crossdamping,how much heparin should begiven? When should the heparin be given?A few minutes prior to aortic or carotid cross-clamping. give 5000 U IV ofheparin. [Dunn, et al., Clin.289. The patient's abdominal aorta has justbeen cross-clamped: what cardiovascularchanges may you see above the clamp?Following abdominal aortic cross-clamp. the following cardiovascularparameters are increased above the cross-damp: end-diastolic volume.end-systolic volume. end-systolic wall stress (tension), systemic vascularresistance (SVR) and mean arterial pressure (MAP). Taken together, theseincreases cause an overall reduction in left-ventricular ejection fractionand cardiac output. [Nagelhout & Zaglaniczny, NA290. 'The patient's abdominal aorta has justbeen cross-clamped: what cardiovascularand metabolic changes may you see below the clamp?Following abdominal aortic cross-clamp. the following cardiovascular and metabolicchanges are seen below the cross-clamp: decreased systemic vascular resistance(SVR) and mean arterial pressure (MAP). decreased tissue perfusion. hypoxialeading to anaerobic metabolism. and lactate accumulation from theanaerobic metabolism. [Nagelhout & Zaglaniczny. NA. 3e. 2005 pp488-490;Miller. Anesthesia. 6e. 2005 pp2073;291. Describe the cardiovascular effects andissues upon release of an abdominal aortic cross-clampFollowing unclamping of the abdominal aortic cross-clamp, there is a"washout" oflocal tissue mediators (e.g., prostaglandins) and metabolicproducts (especially lactate), a decrease in systemic vascular resistance(SVR), and volume shifts leading to a central hypovolemia and ultimatelydecreased venous return to the heart. Decreased venous return leads todecreased cardiac output and potentially significant hypotension. [Nagelhout& Zaglaniczny, NA. 3e. 2005 pp488-490; Miller, Anesthesia292. Describe your plan to manage the potentiallysignificant hypotension followingrelease of an abdominal aortic cross-clamp.The avoidance of significant hypotension with unclamping of an abdominalaortic cross-clamp requires communication with the surgical team,awareness of the technical aspect of the surgical procedure, and appropriateadministration of fluids and vasoactive agents. It is essential thatpreoperative fluid deficits, intraoperative maintenance requirements, andreplacement of blood loss be accomplished before unclamping. Vasodilators,if used, should be gradually reduced or discontinued before unclamping.Potent inhalational agents should be decreased. Moderateintravascular volume loading (approximately 500 mL) during the immediateprerelease period is indicated for infrarenal unclamping. Volumeloading in an attempt to maintain an elevated central venous or pulmonarycapillary wedge pressure during the cross-clamp period is not indicatedand may result in significant overtransfusion of fluids and bloodproducts. Gradual release of the aortic clamp and reapplication or digitalcompression if significant hypotension results are important measures inmaintaining hemodynamic stability during unclamping. [Miller, Anesthesia293. A patient is undergoing surgery thatinvolves clamping of the thoracic aorta.What is a major complication of clamping the thoracic aorta?A major complication of clamping the thoracic aorta is spinal cord ischemiaand paraplegia. The incidence of transient postoperative deficits andpostoperative paraplegia are 11% and 6%, respectively. Higher rates areassociated with cross-clamping periods longer than 30 minutes, extensivesurgical dissections, and emergency procedures. The classic deficit is ananterior spinal artery syndrome with loss of motor function and pinpricksensation but preservation of proprioception and vibration. [Morgan,294. What are the anesthetic goals for intracranialaneurysm surgery?The anesthetic goals for intracranial aneurysm surgery are to avoid aneurysmrupture, maintain cerebral perfusion pressure, and to provide a slack brain295. State 4 steps to take (hint: 3 drugs, 1action) for anesthetic induction and intubationfor the patient undergoing cerebralaneurysm repair.Anesthetic induction for the patient undergoing cerebral aneurysm repairshould be slow and deliberate. (1) Anesthesia may be induced with eitherthiopental (3-5 mg/kg), propofol (1.5-2.5 mglkg) or etomidate (0.5-1.0mglkg). (2) After loss of consciousness and apnea, care must be taken tomaintain a normal PIC02 and to avoid extreme hyperventilation. Vigoroushyperventilation will lower P IC02 decreasing CBF. This may lowerICP to such a degree that if mean arterial pressure (MAP) is maintainedor increased, transmural pressure may be increased, leading to rupture ofthe aneurysm. (3) Fentanyl (3 to 5 mcglkg), sufentanil (0.5 to 1.0 mcglkg),or remifentanil (0.25 to 1.0 mcg/kg) can be added 3-5 minutes beforelaryngoscopy to blunt the hemodynamiC response. Isoflurane/desflurane/sevoflurane is added to deepen the anesthetic. (4) Approximately90 seconds before laryngoscopy, lidocaine (1.5 to 2.0 mg/kg)or esmolol (0.5 mglkg) can be added to further blunt the hemodynamicresponse to intubation. [Yao, Yao 6- Artusio's POPM. 6e. 2008 pp626296. @>Describe the Whipple procedure for pancreatectomyindicated by pancreatic carcinomaA Whipple resection consists of a pancreaticoduodenectomy, followed bya pancreaticojejunostomy, a hepaticojejunostomy, and a gastrojejunostomy297. @>Whatelectrolytedisturbancesareexpectedduring a Whipple procedure?Potential electrolyte disorders in the perioperative period of a Whippleprocedure include: hypocalcemia, hypomagnesemia, hypokalemia, andpossible hypochloremic metabolic alkalosis.298. K'The patient is schedule for a laparoscopiccholecystectomy. During which phase of theprocedure is the patient at the highest risk for serious complications?The patient undergoing Iaparoscopic surgery is at highest risk for seriouscomplications during the initial establishment of pneumoperitoneum.During this period of "access and insufflation" the likelihood ofe02 embolismand hemorrhage, the 2 most dreaded complications oflaparoscopy,is highest. [Nagelhout & Zaglaniczny,299. K'During a laparoscopic procedure thepatient develops a gas embolus. In whatposition should the patient be placed?If a gas embolus develops during a laparoscopic procedure, place thepatient in the left lateral decubitus position. [Nagelhout300. JV'Explain how a carbon dioxide embolusduring laparoscopic surgery may produce a decreased ETCO2In the case of a carbon dioxide embolism. cardiac output decreases and the physiologicdead space increases. Taken together. these changes cause ETC02 to decrease.Carbon dioxide embolization may cause a biphasic change in ETC02.Initially. ETC02 may increase from pulmonary excretion of absorbed carbondioxide. as expected during a C02 embolus. The initial increase in ETC02 is thenfollowed by a decrease in ETC02 as described above.301. A patient is undergoing laparoscopicsurgery and develops a gas embolism. What is your course of action?The treatment of gas embolism is to discontinue gas insufflation, discontinuenitrous oxide, administer 100% oxygen, release the pneumoperitoneum,position the patient in the left lateral decubitus position, and attemptto aspirate gas via a central venous catheter.302. IlList 5 pulmonary function changes associatedwith a pneumoperitoneumInsufflation of the peritoneal cavity causes (I) increased peak inspiratorypressure (PIP), (2) decreased vital capacity (VC), (3) decreased functionalresidual capacity (FRC), (4) increased intrapleural pressure (Ppl), and (5)decreased respiratory system compliance. [Barash, Clin. Anes303. ldentify 7 cardiopulmonary signs andsymptoms ofTURP syndrome.Seven cardiopulmonary signs and symptoms ofTURP syndrome are: (1)respiratory distress (2) cyanosis. (3) hypertension. (4) hypotension. (5)widened QRS or increased ST segment. (6) dysrhythmias. and (7) bradycardia304. ldentify 7 hematologic and renal signsand symptoms o?TURP syndrome Seven hematologic and renal signs and symptoms or TURP syndrome are:(I) Itemolysis. (2) acute renal failure. (3) hyponatremia. (4) hypoosmolarity.(5) hyperglycinemia. (6) hyperammonemia. and (7) coma.IKirby. Clin. Anes. Practice. 2"'305. 'Identify 7 central nervous system signsand symptoms ofTURI' syndromeSeven CNS signs and symptoms ofTURP syndrome are: (I) nausea &vomiting. (2) confusion. (3) twitches. (4) visual disturbances (5) seizures.(6) paralys is. and (7) shock. IKirby306. Coagu1opathies are a possible complicationduring transurethral resection of theprostate (TURP). What are the causes ofcoagulopathies during TURP?Dilutional thrombocytopenia from the large volume ofirrigating solutionsused during TURP is not uncommon. Primary fibrinolysis due toplasmin activation or secondary fibrinolysis due to disseminated intravascularcoagulation may be present Disseminated intravascular coagulation(DIC)-occurring in less than 1% of TURP, especially in patientswith prostate cancer-is caused by release of tissue thromboplastin andurokinase type plasminogen activator (uPA) from the prostate. [Morgan,Mikhail, and Murray, Clin. AnesthesioL, 4th ed., 2006,307. The 65-year-old male patient is undergoingawake surgical resection of the prostategland. The patient suddenly developsnausea and vomiting and abdominal pain.What is the likely cause of these signs and syptoms?Sudden nausea and vomiting and abdominal pain in the awake patientundergoing surgical resection of the prostate gland is most likely due tourinary bladder perforation. The incidence of bladder perforation duringprostate surgery is 1%. Signs and symptoms of bladder perforation areeither extra- or intraperitoneal. Extraperitoneal signs and symptoms ofbladder perforation include: periumbilical, inguinal, or suprapubic pain;lower abdominal distension, and pain in general. Intraperitoneal signs ofbladder perforation are: abdominal rigidity, distension, and pain; referredshoulder pain; hiccups, shortness of breath; tachycardia; hypotension orhypertension; diaphoresis; and, vomiting. Most signs are extraperitoneal and the awake patient complains of nausea, diaphores is. and retropubicor lower abdominal pain. [Morgan308. Idenlify th ree situations thai may prec ip itatecentral pontine myelinolysis. What dothese situat ions have in common?Central pontine myelin olys is is potential complication from TURP syndrome.orthoptic liver transplantation, and head injury. In each of thesesituations, hyponatremia may occur and it is the rapid treatment a/hyponatremiawith hypertonic saline that may lead to central pontine myelinolysis. Correction of'JypotJatremill mllst begradJlal309. What is central pontine myelinolysis(CPM)? Whal are the signs and symploms orce ntral pontine myelinolysis?Central pontine myelinolys is (CPM, aka osmotic demyelination syn·drome) is a neurologic condition characteri zed by symmetric non in·flammatory demyelinating lesions in the basis pontis (anterior portion ofthe pons). Clin ical signs in clude altered level of consciousness progress ingto inability lo speak or swallow (pseudobulbar palsy) and then the class ic"locked· in" syndrome with quad riplegia. CPM is a very serious co nditionthat causes permanent structu ral changes in the brain and often is asso·cialed with dea lh.]Yao. Yao & Artusio 's310. lWhat is strabismus?Strab ismus is misal ignment of the visual axes and is the most frequentophthalmic condition requiring surgical repair. Esophoric strabismusoccurs when one eye is turned inward (nasall y). Exophoric strabismusoccurs when one eye is turned outward (temporally). Ifboth eyes areturned nasally (inward), the proper term is esotropic strabismus311. lldentify 4 anes thet ic concerns for thepatien t undergoing surgical repair of stra·bismus.The four main anes thetic concerns for the pat ient undergo ing surgicalrepair of strabismus are: (I) ca rdiovascular effects of ocular medications;(2) the oculoca rdiac renex; (3) malignallt hyperthermia; and (4) postoperativenausea and vomiting (PONV, occurs in 50-80% of patients pastope·ra liveiy). Strabismus is thought 10 refl eci an underlying myopathy, thusmalignant hyperthermia may be more li kely to develop. Avoid succinyl·choline during strabismus repair surgery. A void opiaids during the pro·ced ure lo dec rease the incidence or PONV312. 'State the desired effects of a retrobulbarblock?The desired effects of a retrobulbar block are 3 <CAs": (1) Akinesia of theeye; (2) Anesthesia of the eye (specifically, the conjunctiva, cornea, anduvea), and (3) Abolishment of the oculocardiac reflex.313. What is the first action to take if thepatient with a double-lumen tube for onelungventilation starts to desaturate?, Ifhypoxia occurs during one-lung ventilation, the position of the doublelumentube should be rechecked using a fiberoptic bronchoscope. After tubepOSition is confirmed, CPAPIO should be administered to the nondependentlung following a tidal volume that expands the lung. According toBarash: "the Single-most effective means to increase PIOZ during one-lungventilation is the application ofCPAP (5-10 em H20) to the nondependentlung." [Barash, Clin. Anes., 5th ed., 2006, pp825-828, 833-834]314. What are the monitoring concerns for thehyperthyroid patient?In the hyperthyroid patient cardiovascular function and body temperaturemust be closely monitored. The goal is early detection of increasedactivity of the thyroid gland, suggestive of thyroid storm onset. Consequently,monitor the ECG for tachycardia and/or dysrhythmias and closelyfollow body temperature.315. List 6 concerns for the patient undergoingradical neck dissection.(1) Weight loss, malnutrition, anemia, dehydration and electrolyte imbalancecan be significant. (2) These patients are often heavy users of alcoholand tobacco and have bronchitis, pulmonary emphysema, and cardiovasculardisease. (3) These patients may present difficult tracheal intubationand airway management problems. (4) Manipulation of the carotid sinusmay elicit vagal reflex that causes bradycardia, hypotension, or evencardiac arrest. (5) Trauma to the right stellate ganglion and cervical autonomicnervous system during right radical neck dissection can (6) Open neck veins create the possibility of air emboli during head andneck surgery. [Miller, Anesthesia. 6th ed., 2005, p2539; Nagelhout316 @During neck dissection, traction or pressureon the carotid sinus can cause arrhythmiaslike bradycardia or asystole, as youknow. What is the definitive treatment forthe arrhythmia? What agents may be given if the arrhythmia persists?The treatment for arrhythmias due to traction or pressure on the carotidsinus during neck dissection is immediate cessation of the stimulus. If thearrhythmia persists, atropine (0.01-0.02 mglkg) or glycopyrrolate (0.01mglkg) can be given. [Dunn, et al., Mass. Gen317. A female patient diagnosed with invasivebreast cancer is having a sentinel node biopsy.What is a sentinel node? Why do youexpect decreased arterial oxygen saturationreadings from the pulse oximeter?A sentinel node is the first lymphatic node to drain a specified region. A sentinelnode biopsy is often done in the patient with small, invasive breast cancer whodoes not have clinically pathologic lymph nodes. The sentinel node is visualizedby injection of either isosulfan blue vital dye (Lymphazurin) or 99m-technitiumlabeledsulfur colloid (TSC). The surgeon should inform anesthesia when injectingthe isosulfan blue dye because a transient drop in pulse oximeter readings of 2-5% is seen frequently. (Jaffe & Samuels, Anesthesiologist's318. @Describethetransverse rectus abdominusmuscle (TRAM) flap procedure for autologousbreast reconstructionThe transverse rectus abdominus muscle (TRAM) procedure replaces thebreast with an ellipse of abdominal skin and subcutaneous tissue based onthe rectus abdominus muscle. The procedure creates a natural appearingbreast from the patient's own tissue. The abdominal donor site is closed asthough the patient had undergone abdominoplasty ("tummy tuck").319. @What drugs should be avoided in thetransverse rectus abdominus mUscle(TRAM) breast reconstruction procedure?In flap reconstructions, the harvested tissue receives its blood supplythrough a single artery and vein. Vasopressors are to be avoided. Manysurgeons prefer that N20 be avoided during the abdominal closure. (Jaffe& Samuels, Surgical Procedures320. Identify the major postoperative concernfor the patient who just underwent an anteriorcervical discectomy.Significant postoperative edema of the larynx and upper trachea should beexpected following an anterior cervical discectomy. The combination oftracheal retraction with the administration of large amounts of fluids maycause severe edema of the larynx and upper trachea321. lThe patient with advanced renal carcinomais scheduled for a radical nephrectomy.List 4 anesthetic concerns for this caseFour anesthetic concerns for the patient undergoing a radical nephrectomyare: (1) acute blood loss, (2) maintain adequate hydration, (3) watchfor signs and symptoms of pneumothorax if the chest is inadvertentlyentered, and (4) venous air embolism is possible. Because the kidney liesin the posterior upper abdomen adjacent to the posterior diaphragmaticattachment, the possibility of an intraoperative pneumothorax exists. Ifthere is unexplained hypotension on closure of the abdomen, suspect apneumothorax. [Barash, CUn322. lWhat is the optimal position for the tip ofa single orifice catheter for aspirating entrainedair from the right atrium?To aspirate entrained air from the right atrium, it is suggested that theoptimal position for the tip of a single orifice catheter is 3.0 cm above thejunction of the superior vena cava and the right atrium323. lWhat is the optimal position for the tip ofa multi-orifice catheter for aspirating entrainedair from the right atrium?To aspirate entrained air from the right atrium, the tip of a multi-orificecatheter should be placed high in the right atrium, at the junction of thesuperior vena cava and the right atrium. [Morgan, Mikhail, and Murray,324. Identify 3 actions for intraoperative ruptureof a cerebral aneurysm.Intraoperative aneurysmal rupture necessitates (1) maintenance of MAPbetween 40 and 50 mmHg or lower to facilitate surgical control of theneck of the aneurysm or of the parent vessel. Alternatively, (2) one orboth carotid arteries may be compressed for up to 3 minutes to produce abloodless field. (3) Blood that is lost should be continuously replaced withwhole blood, blood products, or colloid solution so that intravascularvolume is maintained. [Nagelhout325. What population of patients has thehighest risk for perioperalive recurrence of venous thrombos is?The highest risk for perioperative recurrence of venous thrombosis exis tsfor patients who have experienced thromboemboli during the previousmonth. Elective surgery in these patients should be deferred until a 3-month co urse of warfarin is completed326. In addition to the superior laryngeal andrecurrent laryngeal nerves, what nerve maybe injured during endotracheal intubation?In addi tion to the recurrent and superior laryngeal branches of the vagusnerve (CN X), the hypoglossal nerve (CN XIl) may be injured duringendotracheal intubation. [Nagelhout & Zaglaniczny327. What neuroendocrine changes may occur during laparoscopy?During laparoscopy, excessive intraabdominal pressure and hypercarbiamay activate the sympathoadrenal axis, resulting in increased plasmalevels of epinephrine and norepinephrine. Renin, cortisol, aldosterone,antidiuretic hormone (ADH), and atrial natriuretic peptide levels are alsoincreased. [Yao, fao 6- Artusio's POPM. 6e. 2008328. 'What is rhabdomyolysis?Rhabdomyolysis (literal: "skeletal muscle breakdown") is skeletal musclenecrosis due to muscle tissue injury329. 'List 8 common causes of rhabdomyolysisThe most common causes of rhabdomyolysis are (1) major crush injury,(2) thermal or electrical injury, (3) acute muscle ischemia due to arterialocclusion, (4) acute muscle injury induced by prolonged immobilization,and (5) compartment syndromes, such as occur in hemorrhage or whenvascular insufficiency coexists with edema, (6) malignant hyperthermia,(7) extreme lithotomy position, and (8) hyperlordotic position. [Miller,Anesthesia. 6e. 2005 pp804-S05; Barash,330. v'Which oxygen transport protein releasedduring rhabdomyolysis may precipitate ARF?Myoglobin, the oxygen-carrying pigment of skeletal muscle, and hemoglobinare both capable of causing acute renal failure (ARP). Myoglobinseems to be a more potent nephrotoxin because it is more readily filteredat the glomerulus and can be reabsorbed by the renal tubules, where itinhibits nitric oxide (NO) and induces medullary vasoconstriction andischemia. [Barash, Clinical Anes .. 5e331. Your patient is in hypovolemic shocksecondary to trauma. What anesthetic drugsshould be avoided andlor used cautiously?The following drugs should be avoided in the trauma patient with shock:histamine-releasing muscle relaxants (atracurium and mivacurium) andnarcot ics (morphine and codeine). Induction agents should be used cautiouslyand in small. incremenlal doses332. IIYour patient has a traumatic head injury:which anesthetic drugs are contraindicated and why?Any agent that causes an increase in intracranial pressure (ICP) is contraindicatedin traumatic head injury. Ketamine, succinylcholine, andN20 cause increases in ICP and are contraindicated. All inhalation agentstend to increase ICP-this effect may be attenuated by hyperventilation toPaC02levels of 28-35 mm Hg. [Nagelhout333. During the initial assessment of a traumapatient, you suspect a cervical spine injury.What five criteria increase the risk for potentialinstability of the cervical spine?Five criteria that increase the risk for potential instability of the cervicalspine are: (1) neck pain, (2) severe distracting pain, (3) any neurologicalsigns or symptoms, (4) intoxication, and (5) loss of consciousness at thescene. [Morgan, Mikhail, and Murray334. liThe patient with a cervical spine injurymust be intubated. How is the cervical spinebest stabilized during laryngoscopy and intubation?Manual immobilization of the head and neck by an assistant (manual inlinestabilization, MILS) should be used to stabilize the cervical spineduring laryngoscopy and intubation. [Morgan335. A trauma patient has a partially severedright arm and is at risk for amputation of thelimb. The patient is taken to surgery forreplantation of the limb. What are the specificanesthetic concerns for limb replantation?Microvascular surgery is a key component of limb replantation. The 3anesthetic concerns during replantation and revascularization of a limbare: (l) maintenance of blood flow (increase perfusion pressure, avoidhypothermia, vasodilation, antithrombotics and fibrinolytics), (2) positioning,and (3) replacement of blood and fluid losses. [Barash336. N'Which anesthetic drugs are contraindicatedin burns, traumatic cord injuries, and crush injuries?Succinylcholine may produce dangerous rises in serum potassium levels ifadministered 24 hours after thermal (bum), spinal cord, or crush injuries.[Nageihout & Zaglaniczny, NA337. What inhalational agent causes a varietyof problems in the trauma patient with apneumothorax, pneumocephalus, or pneumoperitoneum?Nitrous oxide (N20) tends to accumulate in closed spaces and thus shouldbe avoided in the trauma patient with a pneumothorax, pneumocephalus,or pneumoperitoneum. [Nageihout338. @lAdministration of fluids during the initialphase of fluid resuscitation after thermalinjury (burn) should be titrated to goalsspecified by Parke, modified Brooke, orclinical end-points. What noninvasive monitoring(hint: laboratory value) may guide fluid mgt?Careful monitoring of the hematocrit may guide fluid management followingthermal injury. An increase in hematocrit during the first daysuggests inadequate fluid resuscitation because hemolysis and sequestrationare actually expected to cause a decrease in this parameter339. vDescribe the pharmacokinetic and pharmacodynamicchanges seen in the burn patientIn general, two things can change the volume of distribution in the burnpatient: changes in extracellular volume, and changes in protein binding.Fluid loss to the burn wound and edema can decrease plasma concentrationof many drugs. About 48 hours after the burn injury, plasma albuminlevels decrease and thus the unbound (free) fraction of albumin-bounddrugs (benzodiazepines, phenytoin, salicylic acid) increases; that is, thesedrugs have an apparently larger volume of distribution. Because thepharmacodynamic effect of a drug is often related to the unbound fraction,alterations in protein binding affect the efficacy and tolerability ofdrug treatment in the burn patient. In contrast, alphal-acid glycoprotein(AAG) levels are increased following burn injury. Drugs that are bound toAAG (lidocaine, meperidine, and propranolol) exhibit a decreased freefraction of drug leading to an apparently reduced volume of distribution.[Nagelhout & Zaglaniczny, NA, 3rd ed., 2004, p804; Duke, Anesthesia340. ?Administration of fluids during the initialphase of fluid resuscitation after thermalinjury (burn) should be titrated to goalsspecified by Parke, modified Brooke, orclinical end·points. If a pulmonary arterycatheter is placed, what three parametersindicate fluid resuscitation is adequate?If a pulmonary artery catheter is placed in the patient with thermal injury,adequate fluid resusc itation is consistent with acceptable cardiac output.filling pressures, and mixed venous oxygen tension (35 to 40 mm-Hg).IBarash, eli,1. Alles.. 6''- 2009 pp911J341. ?What are the guidelines for blood replacementfollowing thermal injury?Following thermal injury, blood replacement is usually not initiated untilthe hematocrit is below IS to 20% in healthy patients requiring limitedoperations, approximately 25% in those who are healthy but need extensiveprocedures, and 30% or more when there is a history of pre-existingcardiovascular disease IBarash, e/ill. Alles.. 6''- 2009 pp9 11342. How do you assess the function of thepermanent intravenous pacemaker leadsonce the leads are placed in the patient?The integrity of placed permanent intravenous pacemaker leads is evaluatedby an external testing device that measures voltage, threshold,impedance, and the amplitude of sensed potentials. At an initial voltageoutput of 5m V and pulse duration of 0.5 ms, the pacing rate is increaseduntil 100% capture occurs. At this point, the voltage output is slowlydecreased to determine the minimum voltage that results in a 100% capturerate (this is the voltage threshold check). The ventricular voltageshould be S 0.8 mV and the atrial voltage should be S 1.5 mY. Lead impedanceshould be 250-1000 Ohm at a nominal output of 5 V. The amplitudeof the sensed potentials is usually> 6 m V and> 2 m V for ventricularand atrial electrodes, respectively. [Morgan, Mikhail343. .#' Evaluation of cardiac pacemaker functionis difficult when the patient's heart rate isfaster than the pacing rate. What maneuvercan the patient do to slow heart rate andreveal the pacing impulses?When a patient's heart rate is faster that the pacing rate of the pacemaker.ask the patient to perform a Val salva maneuver. The Valsalva maneuverslows the patient's heart rate so that pacing impulses appear on the ECG.[Nagelhout & Zaglaniczny, NA. 3e. 2005344.D uring laser surgery. the choice of endotrachealtube (ETT) can affect the safety ofthe technique. Which ETIs are flammable?What modifica tions to the ETr reduce flammability?All standard polyv inyl chloride (PVC) endotracheal tubes are nammable,and can ignite and vaporize when in contact with the laser beam. Onceignited and penetrated. a PVC tube can sustain a torch like name. Redrubber endotracheal tubes wrapped with renective metallic tape do notvaporize. but instead deflect the laser beam. The unwrapped cuff belowthe vocal co rds is still vulnerable to laser inju ry. A silicone tube is moreres istan t to penetration by a C02 laser than other tubes. Ifign ited, a sili -cone tube rapidly becomes a brittle ash that crumbles easily and may beaspirated, raising the possibility of future problems with silicosis. However,the acute injuries are less severe than with red rubber and PVC tubes.Cuffed endotracheal tubes should be inflated with sterile saline to whichmethylene blue has been added so a cuff rupture from a misdirected laserspark is readily detected by the blue dye and extinguished by the saline.[Barash, Clinical Anes .. Se. 2006 ppl006345. Describe the various types oflaserresistantendotracheal tubes.The Laser-Shield II is made from silicone with an inner aluminum wrapand an outer Teflon coating. It is designed for use with C02 and potassium-titanyl-phosphate (KTP) lasers. The cuff is not laser-resistant andcontains methylene-blue crystals. It should be inflated with water or asaline solution. The Laser-Flex tube is a stainless steel tube with a smoothplastic surface and a matte finish to reflect a laser beam. It is designed foruse with C02 and KTP lasers. The wall of the tube is thicker than that ofmost other tubes. The adult version has two PVC cuffs and a PVC tip witha Murphy eye. The two cuffs are inflated by using separate inflation tubesthat run along the inside of the tube. The Sheridan laser tube is a redrubber tube wrapped with copper foil tape. This is overwrapped withwater-absorbent fabric that should be saturated with water prior to use.The Norton tube is a reusable, flexible, spiral-wound metal tube with astainless steel connector and thick walls. The exterior of the tube has amatte finish to decrease reflection of the laser beam. It has no cuff. Aseparate cuff may be attached, or packing around the tube can be used toachieve a seal. Studies show this tube is acceptable for use with KTP, NdYAG,and C02 lasers. It is important to remember that laser-resistant doesnot mean laser-proof. Laser-resistant tubes can ignite, especially if manufacturer'swarnings, precautions, or directions for use are not followed.346. An important concern for both the anesthetistand patient during laser surgery iseye protect ion. Describe the ocular damagethat may occur by the laser, based upon the laser wavelengthUltraviolet (UV) lasers (200-3 IS nm wavelength) may cause co rnealphotokeratitis and cataract formation. Near·UV. visible. and nearinfrared(IR) (400- 1400 nm) lasers-such as Argon, KTP-YAG, Nd:YAG,and ruby lasers-cause retillal damage. Mid-IR (1400-3000 nm) lasersmay cause cataracts and far-lR lasers (3000- 10000 nm), such as the CQ,laser, cause corneal bums. INagelhout & Zaglaniczny347. Can you relyon the color of protectivelenses to indicate their use for specific lasers?If not, what protective eyewear cri teriashould be adhered to for proper ocularprotection during laser surgery?No. you should not rely on the color of protec tive lenses to indicate use forspecific lasers. Protect ive lenses must have the appropriate optical dens ity(aD) and reflective properties based upon the wavelengths of the beamsencountered. For example. protective eyewear for Nd:YAG laser useshould be marked "ODS or greater for 1.064 nm". INagelhout & Zaglaniczny,NA, 3rd ed., 2004, pp9S4-9SSJLeft.348. What factors contribute to the decreasedfunctional residual capacity (PRC) in theneonate and infant during general anesthesia?The chest wall in infants is less rigid (more compliant) because ribs arecartilaginous and not bony. In addition, the boxlike configuration of aninfant's thorax permits less elastic recoil than the dorsoventrally flattenedthoracic cage of the adult does. Additionally, an infant is more wlnerableto muscle fatigue, which may further decrease the stability of the chestwall. As a result of all these factors, an infant's chest wall is extremelycompliant. The net effect of the compliant chest wall and the poorly compliantlungs is a reduced functional residual capacity (PRe). [Miller,Anesthesia. 6e. 2005 pp2842; Davis & Motoyama, Smith's Anes349. 'Is the infant larynx located higher, at thesame, or at a lower level in the neck comparedto the adult larynx? Identify the levelof the infant larynx The infant larynx is located higher in the neck, at the level of C3-4 than inthe adults, where the larynx is located at the level ofC4-5. Author's comment:I find these text statements somewhat misleading-as you know,the cricoid cartilage-certainly part of the larynx-lies at C6, and manytexts (Miller, for example) state that the adult larynx ranges from C3-C6.Perhaps the more accurate statement is: the thyroid cartilage is located atC3-4 in infants compared to C4-5 in adults. [Miller & Stoelting. Basics.5e:2007 pp233; Cote, PAlCo 3e. 2001350. During the preoperative evaluation of a 6-month-old surgical candidate, you notephysiologic anemia. What is a likely causefor the physiologic anemia?The infant with physiologic anemia at 6 months of age is most likely aformerly premature infant (expremie). "Even at several months of age,expremies remain anemic because of poor nutrition and delayed hematopoiesisthat is induced by earlier transfusions." Reminder: the nadir (lowpoint) of physiologic anemia typically occurs at 2-3 months for full-terminfants. [Gregory, Ped. Anes., 41h ed., 2002, p373; Cote, PAIC, 3rd ed.,2001, p20; Yemen, Ped. Anes. Handbook351. Non-shivering (cellular) thermogenesis isa crucial heat-generating mechanism in theneonate and infant, as you know. At approximatelywhat age does non-shivering thermogenesiscease to be clinically significant?Clinically and physiologically significant non-shivering thermogeneSispersists up to the age of2 years. Non-shivering thermogenesis may continueinto adulthood, but generally is not a relevant and significant sourceof heat generation in the adult. [Davis & Motoyama, Smith's Anes. forInfants and Children. 7e. 2006 pp162352. What hemodynamic alteration may worsen(increase flow through) a left-to-right intracardiac shunt?An increase in systemic vascular resistance (SVR) may increase left-torightintracardiac shunt flow, such as occurs in atrial septal defect. Avoidinterventions that may increase SVR in the patient with an ASD.353. A right-to-left intracardiac shunt ispresent in the patient with a ventricularseptal defect (VSD). What hemodynamicalterations may worsen (increase shuntflow) the right-to-left shunt ofVSD?An abrupt increase in pulmonary vascular resistance (PVR) or a decreasein systemic vascular resistance (SVR) is poorly tolerated in the patient withventricular septal defect (VSD). Avoid interventions that may increasePVR or decrease SVR in the patient with a right-to-Ieft intracardiac shunt354. A right-to-left intracardiac shunt ispresent in the patient with a ventricularseptal defect (VSD). What hemodynamicalterations may worsen (increase shuntflow) the right-to-left shunt ofVSD?An abrupt increase in pulmonary vascular resistance (PVR) or a decreasein systemic vascular resistance (SVR) is poorly tolerated in the patient withventricular septal defect (VSD). Avoid interventions that may increasePVR or decrease SVR in the patient with a right-to-Ieft intracardiac shunt.355. Will a right -to-left intracardiac shunttheoretically slow or accelerate inhalationinduction? Is the effect be clinically significantA right-to-Ieft intracardiac shunt will theoretically slow inhalation induction,because less anesthetic is absorbed from the lung, and mixing willfurther dilute blood passing to the left, decreasing the arterial concentrationof the blood going to the brain, especially the less soluble agents. Thiseffect is rarely problematic. [Fleisher, Anesthesia356. WilI a right-to-Ieft intracardiac shunttheoretically slow or accelerate intravenous induction?An intravenous induction will be theoretically accelerated with a right-toleftintracardiac shunt. [Fleisher357. 'Will a left-to-right intracardiac shunttheoretically slow or accelerate inhalationinduction? Why is this phenomenon rarely evident clinically?A left-to-right intracardiac shunt should accelerate the speed of inhalationinduction because the rate of transfer of anesthetic agent from the lungsto the blood is increased. However, this effect is rarely clinically evidentbecause decreased delivery of anesthetic to the target tissues negates theincreased uptake of agent with a left-to-right intracardiac shunt. [Fleisher,Anesthesia and Uncommon Disease, 5th ed., 2006 p91; Barash358. Will a left-to-right intracardiac shunttheoretically slow or accelerate intravenousinduction? Why is this phenomenon rarely evident clinically?Intravenous induction should be slowed by a left-to-right shunt; however,unless cardiac output is very poor, the effect is clinically irrelevant[Fleisher, Anesthesia359. Describe the suggested tracheal intubationtechnique for a patient with Treacher Collins syndromeTreacher-Collins syndrome is the most common of the mandibulofacialdystoses, a group of syndromes that feature mandibular hypoplasia. Inaddition, up to 30% ofTreacher-Collins patients have an associated cleftpalate. An awake tracheal intubation (oral or nasal) with aid of a fiberopticlaryngoscope after adequate topical anesthesia is recommended. Milleradvocates: (1) topicalization with 1% lidocaine, (2) LMA insertion, followedby (3) fiberoptic intubation through the LMA. Also consider fiberoptictracheal intubation after induction with a volatile agent. [Stoelting& Dierdorf, Handbook of Anesthesia and Co-Existing360. ?Treacher-Collins syndrome is associatedwith cleft palate, as you know, indicating adifficult airway. What congenital heartdisease is associated with Treacher-Collins syndrome?Treacher-Collins syndrome is frequently accompanied by congenital heartdisease, most prominently ventricular septal defect. Concept: ventricularseptal defect is the most commonly occurring congenital heart disease,therefore VSD is frequently associated with many other congenital anomalies.[Hines, Stoelting's Co-existing. 5e. 2008 pp613; Yao, Yao 6- Artusio's361. @)In addition to cleft palate and ventriculo septaldefects. what other conditions areassociated with Treacher-Collins syndrome?Is a macroglossia (large tongue) associated with Treacher-Collins syndrome?Treacher-Collins syndrome is associated with cleft palate (30%). venlriculoseptaldefect (VSD), malar hypoplas ia, colobomas (notching of thelower eyelid s), macrostomia (large mouth), malocclusion, and a smalloral cavity. Treacher-Collins syndrome is not associated with macroglossia(large tongue) or mental retardation.362. @) List three (3) treatments for postintubationlaryngeal edema (postintubation “croup”Treatment of postintubalion laryngeal edema ("croup") is aimed at reducingairway edema. Mild cases of len improve with cool, humidified mistand oxygen therapy. ideally administered by a face tenl. More severe cases require hourly administration of aerosolized racemic epinephrine, 0.05mLlkg of 2.25% epinephrine in 3.0 mL of saline. Intravenous dexamethasone(0.25-0.5 mglkg) may prevent the edema, but the effect takes up to4-6 hours to manifest363. @Identify ten (10) factors associated withpostintubation laryngeal edema ("croup").The following ten factors are associated with postintubation laryngealedema ("croup"):(1) age younger than 4 years, (2) tight-fitting endotracheal tube, no audibleleak at 15-25 em H20, (3) traumatic or repeated intubation, (4) prolongedintubation, (5) high-pressure, low-volume cuff, (5) patient "bucking"or coughing during intubation, (6) head repositioning whileintubated, (7) history of infectious or postintubation croup, (8)neck/airway surgery,(9) upper respiratory infection, and (10) Trisomy 21.364. @What is the most common cause for livertransplantation in children?In children, the most common cause for liver transplantation is cholestaticliver disease secondary to biliary atresia, particularly in infants (50%).365. Positive pressure ventilation by bag andmask has been instituted on the neonateduring resuscitation. When is endotracheal intubation indicated?During neo natal resuscitation, prompt endotracheal intubation is indicatedif there is no immediate ?30 seconds) improvement in the clinicalco ndition of the neonate with positive-pressure ve ntilation with a facemask. (There are many steps in the algorithm for resuscitat ion of thenewly born in fant at which endotracheal in tubation may be considered:see Chestnut, page 133 for the complete algorithm.)366. When should immediate endotrachealintubation be considered during neonatal recussisation?Immediate endotracheal intubation of the neonate should be consideredfor situations in which bag and mask ve ntilation is likely to be ineffective,for example. extreme prematurity with low pulmonary compliance secondaryto surfactant deficiency. Other situat ions in which bag and maskven tilation may be ineffective are large bilateral pleural effusions andcongenital diaphragmatic hernia367. What size (French) suction cathetershould be used to clear the endotrachealtube of the intubated neonate? The intubated2-year-old? The intubated 6-year-old?The appropriate size (French) of suction catheter for clearing the endotrachealtube of the intubated child is: neonate-8 Fr, 6 months to 2 yearsold-IO Fr, and 2 to 12 years 01d-14 Fr368. Surgery in neonates poses a major concern-development of apnea in the postoperativeperiod. Which neonates are at thehighest risk for postoperative apnea?Neonates at highest risk for postoperative apnea are those born prematurely,those who have multiple congenital anomalies, those with a historyof apnea and bradycardia, and those with chronic lung disease369. Would a formerly premature infant be acandidate for outpatient surgery? What arethe anesthetic concerns for the formerly premature infant?No, the formerly premature infant is not an appropriate candidate foroutpatient surgery. Formerly premature infants (less than 46 weeks postconceptualage), even ifhealthy, have an increased rate of post-anestheticapnea and bradycardia. These formerly premature infants should havecardiorespiratory monitoring for a minimum of24 hours postoperativelyand thus are not good candidates for ambulatory day surgery370. The infant patient is high-risk for postoperativeapnea what agent may be givenprophylactically to decrease the risk of apnea?The infant at risk for postoperative apnea may be given caffeine prophylacticallyto ensure adequate serum levels exist prior to surgery and during the postoperativeperiod. Caffeine is a respiratory and CNS stimulant and is generally preferredto theophylline because caffeine has a wider therapeutiC margin and a decreasedpropensity for toxicity. The recommended loading dose is 10 mglkg of caffeinebase, which is often obtained from 20 mg of caffeine citrate. The clinical effects ofcaffeine may last several days after a single dose, but do not administer caffeineand then discharge the patient, assuming that the caffeine will prevent apnea371. ?What is retinopathy of prematurity?Retinopathy of prematurity (ROP), formerly known as retrolental fibroplasia,is a fibrovascular proliferation overlying the retina that leads toprogressive visual loss. ROP occurs almost exclusively in preterm infants.The risk ofROP is inversely proportional to birth weight, and is associatedwith neonatal oxygen exposure, apnea, blood transfusion, sepsis,and fluctuating levels of carbon dioxide. [Cote, PAlCo 4th. 2009 pp64;372. @) At what gestational age does the risk ofretinopathy of prematurity become negligible? Why?The risk of retinopathy of prematurity becomes negligible after 44 weekspostconception because retinal vasculogenesis is complete between 42-44weeks postconception.373. What is the appropriate volume for apediatric epidural blood patch?In the child who is awake, the practitioner should stop the blood infusiononce the child feels discomfort of pressure in the back. In the anesthetizedpatient, no more than 0.3 mLlkg of blood should be injected into theepidural space.374. ,..-State 3 reasons why the uptake of anestheticdrugs is typically faster in children than in adults.Uptake of anesthetic drugs is faster in children than adults for the following3 reasons. (1) The Childs higher alveolar ventilation per weight accountslargely for this effect. (2) Increased cardiac output with greaterdistribution to the vessel-rich groups combined with lower muscle massallows more of the agent to concentrate in vital organs, especially thebrain. (3) Anesthetic agents appear to be less blood soluble in childrenthan in adults, that is, the agents work faster in children than adults.375. What is the most commonly used analgesicfor pediatric outpatients?Acetaminophen is the most commonly used mUd analgesic for pediatricoutpatients. The initial dose is often administered rectally (up to 45mglkg) prior to awakening from anesthesia. Supplemental doses are thengiven orally (10 mglkg every 4 hours or 20 mglkg every 6 hours) to maintainadequate blood levels and effective analgesia.376. What is the drug of choice and dosing forprophylaxis for pediatric endocarditis?Standard general prophylaxis for pediatric endocarditis is amoxicillin, 50mglkg orally 1 hour prior to procedure.377. The pediatric patient is scheduled for aradiofrequency ablation of an aberrantconduction pathway (e.g., Wolff-ParkinsonWhitesyndrome). Why is a general anesthetictypically required for this scenario?Radiofrequency ablation is a nonsurgical approach designed to eliminateatrial or ventricular re-entrant tachyarrhythmias. The technique requiresmapping and precision ablation of the aberrant pathway, using a radiofrequencyablation catheter. During the ablation, unexpected movementmay result in catheter dislodgment and damage to normal conductingtissue; therefore, general anesthesia is usually required in younger children.Anesthetic agents and techniques should be chosen to maintaincirculating catecholamines and avoid suppression of arrhythmogenesis,for identification of the aberrant pathway. [Miller,378. @Describe the 4 steps to treating hyperkalemiain the neonateEmergent treatment of hyperkalemia in the neonate centers around antagonizingthe cardiac effects of excess potassium-administer calcium ascalcium chloride (0.1-0.3 mL/kg of 10% solution) or calcium gluconate(0.3-1.0 mLlkg 10% solution) over 3-5 minutes. Return potassium to theintracellular space by correcting acidosis through sodium bicarbonate, mild hyperventilation. and a ~-agonist. Maintain potassiumin the intracellular space by glucose + insulin infusion, 0.5-1.0g/kg glucose with 0.1 U/kg insulin over 30-60 minutes). Remove wholebodypotassium burden by Kayexalate or dialysis and correct the underlyingetiology. [Cote. PAle. 4''- 2009 ppl72-173J379. ?An infant has a life-threatening succinylcholine-induced hyperkalemia: what is Lhe definitive treatment?The definitive treatment of succinylcholine-induced hyperkalemia is IVcalcium (10 mg/kg calcium chloride or 30 mg/kg calcium gluconate ormorc), This restores the gap between the resting membrane potential ofthe cardiac cells and the threshold potential for depolarization. Repeateddoses of calcium must be administered together with cardiopulmonaryresuscitation, epinephrine, sodium bicarbonate, glucose and insulin. andhyperventilation until the arrhythmias abate. [Cote. PAle. 4,h 2009380. "Which maternal hemodynamic parametershows the greatest decrease during normal gestation?During normal gestation, the greatest decrease in a hemodynamic parameteroccurs in the systemic vascular resistance (-20% SVR). [Chestnut,Obstetric Anesthesia, 3rd ed., 2004, p18t381. Which maternal hemodynamic parametershows the greatest increase during normal gestation?During normal gestation, the greatest increase in a hemodynamic parameteroccurs in the cardiac output (+50% CO).382. Identify 3 maternal physiological disturbancesthat pose the greatest risk to the fetusThe greatest risk to the fetus occurs following maternal catastrophesinvolving (1) severe hypoxia, (2) hypotension, and (3) acidosis. [Chestnut383. What is the most serious fetal risk associatedwith maternal surgery during pregnancy?The most serious fetal risk associated with maternal surgery during pregnancyis that of uterine asphyxia384. Describe plasma cholinesterase (pseudocholinesterase)changes in the pregnant patientPlasma cholinesterase (pseudocholinesterase) levels will decrease by 24%before delivery and decrease further (to 33% less) by 3 days postpartum.[Hughes, Anes.for OB, 41h ed., 2002, p13]385. After parturition, how long does it takefor plasma cholinesterase (pseudocholinesterase)levels to return to normal?Plasma cholinesterase (pseudocholinesterase) levels will return to normallevels in 2-6 weeks postpartum386. @)How does minute ventilation changeduring pregnancy?Minute ventilation increases by up to 45% during pregnancy. [Barash, DBAnes .. 4th. 2009387. @)What respiratory parameter changes mostto increase minute ventilation during pregnancy?What physiological factors promptthe increase in minute ventilation during pregnancy?During pregnancy, resting minute ventilation increases (up to 45%) owingprimarily to an increase in tidal volume, with minimal, if any, changein inspiratory rate and pattern. The rise in minute ventilation results fromhormonal changes (increased progesterone) and increased C02 production.Progesterone acts as a direct respiratory stimulant and the progesterone-induced increase in chemoreceptor sensitivity results in a steeperand leftward shifted C02 ventilatory response curve388. @)What is the earliest sign of magnesiumtoxicity?Clinically, the therapeutic effects of magnesium therapy are estimated bythe response to deep tendon reflexes. Marked depression of deep tendonreflexes is an indication of impending magnesium toxicity. At therapeuticmagnesium levels (4-6 mEq/L), lethargy, nausea & vomiting, and facialflushing may occur. At magnesium levels greater than 6 mEq/L, loss ofdeep tendon reflexes and hypotension ensue. [Miller389. @)State the loading and maintenance dosesof magnesium sulfate administered forseizure prophylaxis in pregnancy-induced hypertension?For seizure prophylaxiS in pregnancy-induced hypertension (preeclampsia),magnesium sulfate is administered at a loading dose of 4-6 g over20-30 minutes, followed by a maintenance dose of 1-2 glhr, continuedfor up to 24 hours postpartum. [Barash390. @l What specific changes are often seen inthe ECG when magnesium levels reach 10 meq/L? At magnesium levels of 10 mEq/L. prolonged P-Q intervals and widenedQRS complexes may be observed. Asys tole occurs at 20 mEq/L. [Yao. Yao&Artllsios POPM. 6e. 2008 pp9171391. v'Does magnesium sulfate cross the placen ta?What effects can magnesium sulfate have on the fetus?Magnesium sulfate may cross the placenta and potentially cause hypermagnesemia in the fetus. Hypermagnesemia in the felus results in loss ofbeat-to-beat variability in fetal heart rate, hypo reflexia, muscle weakness.and respiratory depreSSion (apnea ).392. ,.,Identify the drugs that are compaliblewith the mother who is breast-feeding her infantMost drugs are safe during lactation. Typically only 1% to 2% of lhe maternaldose appears in breast milk. Lithium and ergotamine are bestavoided during lactation. [Chestnut393. The parturient has received a neuraxialopioid and is experiencing nausea and vomiting.Which drug is particularly effectivefor opioid-induced nausea and vomiting in laboring women?Ondansetron (Zofran) is effective for the treatment of opioid-inducednausea and vomiting in laboring women, and it also has few side effects.[Chestnut, DB Anes .. 3rd. 2004394. The parturient has received a neuraxialopioid and is experiencing nausea and vomiting.Which drug is effective for opioidinducednausea in laboring women, but has but has the most significant SE?Droperidol is effective for the treatment of nausea in laboring women, butit has significant side-effects, namely dysphoria, akathisia (an unpleasanttsensation of "inner restlessness" accompanied by the inability to sit still),and oculogyric crisis. Furthermore, the FDA has issued a "black box"warning because of the concern that the administration of droperidol mayresult in an increased risk of cardiac arrhythmias395. Identify the most common cause of anesthesia-related maternal mortality on the obese parturientThe most common anesthesia-related cause of maternal mortality in theobese parturient is airway complications396. ,*,What is the appropriate positioning forthe parturient with amniotic fluid embolismif the fetus has not yet been delivered?For the parturient with amniotic fluid embolism (AFE) from whom thefetus has not been delivered, left uterine displacement is appropriate,along with slight head-up position, with left lateral tilt of at least 15 degrees.397. ,*,Identify 5 signs and symptoms of venousair embolism in the pregnant patient.Signs and symptoms of venous air embolism in the pregnant patient are(1) mill-wheel murmur detected over the pericardium, (2) chest pain, (3)dyspnea, (4) decreased end-tidal CO2, and (5) elevated central venouspressure. Late signs of venous air embolism are hypotension, tachycardia.and cardiac dysrhythmias.398. ,*,The obstetric patient develops a venousair embolism-in what position will youplace the parturient?The parturient who develops a venous air embolism (incidence as high as9596) should be placed in a slight anti-Trendelenburg position with leftlateraltilt of IS. This position increases the likelihood of trapping air inthe right atrium, from which it can be aspirated via a central venouscatheter.399. Your patient has mitral stenosis and isbeing prepared for an emergent cesareansection. The patient has not been adequatelyhydrated and hypotension is a concernwhichanesthetic technique will you useA general anesthetic would be the technique of choice for emergent cesareansection when hypotension is a major concern. Although regional andneuraxial techniques are viable options, hypotension is more commonwith these techniques, compared to general anesthesia. Hypotension ismost common with a spinal anesthetic, less common with epidural anesthetics,and modestly less common with a regional technique; a generalanesthetic is associated with the least likelihood of hypotension400. A parturient has ges tational diabe tesmellitus and is hyperglycemic on admissionfor labor and delivery. Will her infant benormoglycemic, hypoglycemic, or hyperglycemic? Why?Neonatal hypoglycemia occurs in 5% to 12% of cases of pregestational andgestational diabetes mellitus (OM). The neonatal hypoglycemia is pre·sumed to result from sustained fetal hyperinsulinemia that develops inresponse to chronic intrauterine hyperglycemia. Decreased fetal oxygensecondary La uncontrolled maternal OM may also promote hypoglycemiain the fetus and newborn. [Chestnut, OB401. 'Elderly patients have changes in autonomicfunction referred to as physiologicbeta blockade. Identify two cellular changesthat explain the blunted ~-receptor responsein the geriatric patient. What two cardiovascularresponses are altered due to theblunted ~-receptor response?Decreased ~-receptor responsiveness is secondary to both decreasedreceptor affinity and alterations in signal transduction (specifically,decreased intracellular cyclic AMP). Decreased ~-receptor responsivenessassumes functional importance when increased flow demands are placedon the heart. Normally, ~-receptor-mediated mechanisms act to increasethe heart rate, venous return, and systolic arterial pressure while preservingpreload reserve. [n contrast, the attenuated ~-receptor response in theelderly during exercise/stress is associated with (1) decreased maximalheart rate and (2) decreased peak ejection fraction. Such decreases causethe increased peripheral flow demand to be met primarily by preloadreserve, thereby making the heart more susceptible to cardiac failure.402. What two important changes in the autonomicnervous system (ANS) take place with aging?The two most important changes in the autonomic nervous system withaging are a decrease in response to ~-receptor stimulation and an increasein sympathetic nervous system activity.403. What is tumescent liposuction?"Tumescent" means distended, especially by fluids or gas. and comesfrom the same Latin root as "tumor." During tumescent liposuction. acombination of IV fluid, dilute lidocaine 0.05% to O. I %, and dilute epinephrineI: 1 ,000,000 (collectively called the wetting solution) is used toemulsify fa t, provide anesthesia, and create hemostasis during liposuction404. Identify the ratio of wetting solution tovolume of fat 10 be removed for tumescentliposuction. What is the anesthetic concern with this ratio?For tumescent liposuction, a ratio of 1 mL of wetting solution to each mLof fat to be removed is commonly employed. With liposuction volumesapproaching the 4000- to 5000-mL range (or greater), a chief concern isfluid volume overload. Fluid volume overload may promote hypoxemia,hypertensi011, andlor postoperative pulmonary edema. !Jaffe & Samuels.Anesthesiologist's Manual of Surgical Procedures405. What accounts for up to 25% of deathsduring liposuction?PE accounts for 25%406. @)Clinical improvement follOwing an epiduralsteroid injection correlates with three(3) pathophysiologic findings at the nerveroot. What are these 3 findings?Epidural steroid injection provides relief from acute radicular pain whenthe nerve root(s} exhibits: (1) edema, (2) inflammation, and (3) increasedlevels of phospholipase A2 (PLA2) expression.407. @)Which nerve fibers appear to be affectedby epidural steroids?Local applicatio~_ of methylprednisolone was found to reversibly blocktransmission in the unmyelinated C-fibers. but not in AfJfibers.{Cousins& Bridenbough. Neural Blockade. 4th. 2009 pp 1074408. @What procedure is generally effective forsymptomatic relief of acute radieulopathy( nerve root compression)?Epidural steroid inj ections are effective for relief of pain associated withacute radiculopathy (nerve root compression). [Morgan, et aI., Clin.409. @With respect to the onset of acute radiculopathy.what appears to be the optimal timeframe for epidural steroid injection? Forhow long can an epidural steroid inj ectionbe expected to provide pain relief from acute radiculopathy?Epidural steroid injections are most effective when given within 2 weeksof onset ofpaitl and do not appear to provide long-term pain relief beyond3 months410. @Identify the two most commonly usedsteroidal agents and their dosing for epiduralsteroid injections. In what kind of mixture is the steroid often injected?The two most commonly used agents for epidural steroid injection aremethylprednisone acetate (Depo-Medrol) 40-120 mg. and triamcinolonediacetate (Aristocort), 40-80 mg. The steroid is injected either alone, witha saline diluent, or in mixture with a local anesthetic. [Morgan, et aL, ClilLAlles/h .. 4e. 2006 pp404; Cousins. Neural Blockade411. @What advantagesdoa local anesthetic andsteroid mixture provide (or an epiduralsteroid injection? What are the disadvantagesof administering the local anesthetic in combination with a steroid?A mixture of local anesthetic and steroid for the epidural injection may behelpful if the patient has muscle spasm and the local anesthetic providesimmediate pain relief until the steroid's anti-inflammatory effects takeplace (12-48 h). Injection of a local anesthetic carries the risks of intra thecal,subdural, and intravascular complications, such as hypotension,arrhythmia. and seizure412. Neurolytic blocks arc not permanentbecause of the agents used to temporarilydestroy nerve fibers or neural ganglia. Identifythe 2 agents most commonly used toperform neurolytic block and the appropriate concentration for each agentTemporary destruction of nerve fibers or ganglia is typically accomplishedby injection of alcohol (50-100%) or phenol (6- 12%). Ethyl alcoholcauses temporary destruction of nerve fibers or ganglia by causingextraction of membrane phospholipids and precipitation of membraneproteins. Phenol appears to cause temporary des truction of neural tissueby coagulation of proteins. [Morgan413. @Ust three (3) approaches to the epiduralspace ror an epidural steroid inj ec tion. Whatis the recommended volume for injectionwith each route?The epidural space can be approached through the interlaminar space(med ian or paramedian), the int ervertebral foramen (lransforaminai,"selective nerve block"), or the sacral hiatus (caudal). When using a caudalapproach, 20 to 25 mL or a solution has been recommended to assureepidural spread cephalad to the desired level. When using a lumbar inlerlaminarapproach, a volume of 5 to 10m L has been recommended toreach those areas most commonly involved in the lumbar reg ion. A volumeof2-3 mL is lIsed for the transforaminal approach414. ?Which of the three approaches to anepidural steroid injection requires the use ofradiographic imaging for needle placement?The transforaminal ("selective nerve block", intervertebral) approachrequires the use of radiographic imaging ifit is to proceed with safety.415. What is the primary indication for aneurolytic block?Neurolytic blocks are indicated for patients with severe, intractable cancerpain. [Morgan416. Are neurolytic blocks permanent or temporary?Neurolytic blocks are not permanent. Neurolytic blocks may last from 2-6months.417. vWhat procedure should be done prior to a neurolytic block?At least one diagnostic block with local anesthetic should be done beforeconsidering any neurolytic technique. This serves to confIrm the painpathway(s) involved and to determine the potential efficacy of the neurolytic block418. @)What is the most effective measure forpain associated with pancreatic cancer?Celiac plexus block with alcohol or phenol is the most effective interventionfor treating pain associated with pancreatic cancer419. Identify the 4 most common neurolyticblocks performed in cancer patients with intractable painThe 4 most commonly employed neurolytic blocks in cancer patients withintractable pain are: (1) celiac plexus; (2) lumbar sympathetic chain; (3)hypogastric plexus; and, (4) ganglion impar (retroperitoneal plexus).Neurolytic techniques are sometimes used for somatic or cranial nerves oreven neuraxial blocks.420. @)What nerves when blocked may providerelief from cluster headaches? Block orablation of which nerve ganglion may providerelief from cluster headaches?The greater occipital nerve block is commonly used for primary headachesyndromes; for chronic syndromes, the anterior region involving thetrigeminal nerve is also blocked. It has been reported for use with cervicogenicheadache, OCcipital neuralgia, migraine, and cluster headache.Sphenopalatine ganglion neurolytic block can be used to treat headacheand facial pain.421. List two exceptions to the statute oflimitationsfor ftling a lawsuit claiming negligenceTwo exceptions to the statute of limitations for ftling a lawsuit are: (1) theplaintiff is under a disability which keeps the plaintiff from bringing thesuit (e.g., children, persons under legal guardianship), and (2) the plaintiffmay not have been able to discover that there was an injury caused bynegligence before the statute oflimitations expired. Note: the statue oflimitations varies by state, by nature of the case and by the circumstancesof the case.422. @)What is the most common cause of malpracticeclaims against anesthesiologists?Tooth damage is the most common cause of malpractice claims againstAnesthesiologists423. Which amendment to the United StatesConstitution gives the states the right toenact laws to protect the health and safety of their citizens?The Tenth Amendment to the United States Constitution reads: "Thepowers not delegated to the Unites States by the Constitution, nor prohibitedby it to the States, are reserved to the states, respectively, or to thepeople." The Tenth Amendment is the source of the states "police power"or right to regulate the public health, welfare, and safety (Dent v WestVirginia, 1889424. List the 6 elements of informed consentThe six elements of information that are required for consent are: (1) thepatients diagnosis, (2) the general nature and purpose of the anticipatedprocedure, (3) the risks and consequences involved, (4) the prospects ofsuccess, (5) the prognosis if the procedure is not performed, and (6) thealternative methods of treatment available, if any. [Waugaman, Principlesand Practice425. What principle mitigates the informationprovided to obtain patient consent?The duty to disclose is measured by the amount of knowledge the patientneeds. [Waugaman426. What four elements must be proved whenapplying the doctrine of res ipsa loquiturIn order to apply the doctrine of res ipsa loquitur ("the thing speaks foritself), the following four elements must be proved: (I) the injury is of akind that typically would not occur in the absence of negligence, (2) theinjury must be caused by something under the exclusive control of theanesthesiologist, (3) the injury must not be attributable to any contributionon the part of the patient. and (4) the evidence for the explanation ofevents must be more accessible to the anesthesiologist than to the patient427. What is amicus curiae?Amicus curiae literally is "friend of the court." During the appeal process,an appellate court permits persons who are not parties to the case toprovide relevant information to the appellate court on the law to be applied.The procedure used to provide this relevant information is a briefamicus curiae. a brief filed as a "friend of the court."428. @List four characteristics of researchResearch can assume many different forms. Research should be valid.both internally and externally. Research must be reliable, which refers toth e extent to which data coll ection. analysis, and interpretation are consistentand to which the research can be replicated. And finally. researchmust be systematic. [429. @ldentifytheeight(8) stages of the researchprocess.The research process is defined as consisting of the following eight distinctstages: (I ) identification of the problem; (2) review of the relevantknowledge and literature; (3) formulation of the hypothesis or researchquestion; (4) development of an approach for tes ting the hypothes is; (5)execution of the research plan; (6) analysis and interpretation of the data;(7) dissemination of the findings to interested colleagues; and (8) evaluationof the resea rch report. [Nagelhout430. @Oefine"hypothesis." What does a hypothesis establish?In its most elemental form. a hypothes is is either a proposition of thesolution to a problem or a stated relationship among variables. A hypothesisestablishes and defines the independent variable (the variable to bemanipulated or is presumed to influence the outcome) and the dependentvariable (the outcome that is dependent upon the independent variable).The hypothes is is declara tive in structure431. @State three (3) forms a hypothesis maytake.A hypothes is may be a directional hypothesis. A direc tional hypothesis willinclude the words less or more. A notldirectional hypothesis states there isa difference wi thout specifying the direction of the difference. The thirdtype of hypothes is is the null hypothesis. which states there is tlO differencein the relat ionship or proposed solutions to the problem432. @lThere are many ways to class ify researchmethods. One of the more popular ca tegori zationsis to separate the methods into ob servaliorlaland experimental (interve1Itio1/ al)sludies. Briefly describe each methodObservational studies are those in which data is gathered without performingand specific intervention affec ting the ass ignment of groups oreffects on group members. In an experimental study, subjects are assignedto groups, an intervention(s) is performed. and attempts are madeto eliminate bias and confounding va riables before the data are collected433. @Observational studies rna)' be classified ascase-se ries, case-control. cross-sectional, orcohort studies. Describe a case-series.In a simple case-series, the author describes some interes ting or intriguingobservations that occurred for a small number of patients. Thereare no co ntrol subjects. thu s the case-study does not have the nature of"proving" something. but often leads to a hypoth es is and subsequentinvest iga tion434. @)Howdocase-control and cohort stud ies differ?Cohort and case-control studies are called longitudinal studies becausethey are involve an ex tended period of time defin ed by point when thestudy begins and the paint when it ends. A case-cont rol sludy begin "at the end" with the presence or absence of an outcome and then looksbackward in time to try to detect possible causes or risk factors that mayexplain the outcome. Therefore, a case-control study is a retrospectivestudy that asks, "What happened?" In a cohort study, the researchersselect group of people who have something in common, say a risk factor,and then monitor the cohort forward in time. A cohort study asks, "Whatwill happen?" and thus is a prospective study435. @What is "bias" in a research method?Bias is a systematic effect in the study that produces an error on our interpretationof the results. Several types of bias exist; some of the morecommon biases are: selection bias, confounding bias, and measurementbias.436. ? Describe selection bias.Selection bias occurs when two groups are compared with respect to somevariable without acknowledging or realizing that the groups are differentin other important ways437. @Define confounding bias.Confounding bias occurs when multiple variables are intertwined so thatalthough we may assume the variable under study is important, the truthis that the confounding variable may be more imp438. ?Describe measurement biasMeasurement bias occurs if the methods used for making measurementswhen comparing different groups have different scales or sensitivities.Measurement bias may be avoided in a blinded study439. @What does the term blinding refer to?What may be avoided by doing a blinded study?The term blinding (or masking) refers to the process of controlling forobvious and occult biases arising from the subjects' or researchers' reactionto what is taking place. In a blinded (or masked) study, measurementbias may be avoided if the person performing the measurement does notknow which group is being measured. This is called a single-blind study.In a double-blind study, neither the researcher nor the subject is aware ofwhich treatment or manipulation the subject is receiving. In eitherblinded study, measurement bias is avoided440. ?What type of research design method isthe "gold standard" and why is this so? Whatare the disadvantages to this "gold standard design”?The idealized "gold standard" research design in medical research is therandomized clinical trial (RCT). The ReT is ideal because: (I) the subjectsare randomly assigned to the research groups, minimizing selection bias;(2) the study is prospective (looking forward in time); (3) the dependentvariable is measured; (4) it provides the greatest justification for concludingcausality; and (5) it is subject to the least number of biases. The greatestobstacles to RCTs are the great expense, efforts needed, and durationof the study. To minimize and overcome these disadvantages, RCTs areoften carried out as multi-center trials. [Nagelhout, NA. 4th. 2009 pp55;B441. @>As with research study design methods,there are many ways to categorize types ofdata and measurements. Nagelhout categorizesdata in 4 categories. List the four categoriesof measurement/data typesThe four levels or degrees of measurement or data types are: nominal,ordinal, interval, and ratio. For reference, one of the other popular categorizationof measurements is: nominal, ordinal, and numerical. Nominaland ordinal measurements are often called qualitative observations, whereasinterval and ratio measurements are called quantitative observations.Both interval and ratio measurements are continuous in nature442. @>Give the characteristics of nominal measurementsand some examples of nominal dataNominal scales are used for the simplest types of data that fit into categories.Nominal measurements simply identify the data. If there are only twocategories of data, for example male and female, the observations arebinary or dichotomous. An example of observations with more than twocategories would be blood types (A, B, AB, 0) and eye color443. @>Give the characteristics of nominal measurementsand some examples of nominal dataNominal scales are used for the simplest types of data that fit into categories.Nominal measurements simply identify the data. If there are only twocategories of data, for example male and female, the observations arebinary or dichotomous. An example of observations with more than twocategories would be blood types (A, B, AB, 0) and eye color. [Nagelhout,NA. 4th. 2009 pp55; Dawson & Trapp, Basic Bi444. <i>Give the characteristics of ordinal measurementsand some examples of ordinal dataWith ordinal measurements, observations are still classified by categories,but some observations may have more or are greater than other observations,and thus are ordered or ranked. Examples of ordinal data includeorder of race finish (l st, 2nd, 3fd, etc), pain scores, and the ASA classificationscheme (ASA Class I, ASA Class II, etc.).445. Give the characteristics ofinterval measurementsand some examples of interval dataInterval observations measure the quantity of something for which thedifferences between the numbers have meaning on a numerical scale builtupon equally spaced intervals. Technically, interval data does not have anabsolute zero point on the scale. Examples are temperature on the Fahrenheitor Celsius scales, calendar years, or the IQ scale. The distance(interval) between adjacent measurements is meaningful and quantifiable,not simply "more" or "less."446. @>Give the characteristics of ratio measurementsand some examples of ratio data.Ratio measurements are quantitative, numerical observations that can beordered and equally spaced, but which are based upon a numerical scalethat has an absolute zero point. Examples of ratio data are the temperatureon the Kelvin scale (absolute temperature), blood pressure, distance,and height. [Nagelhout447. @What is operationalization?Operationalization is the process of making the characteristics inherent ina given variable, condition. or process clear and familiar to others. Forexample, if a study examined critically ill patients it would be essential tooperationalize the term "critically ill patients" in order to clearly delineatethe term so that the research might be replicated without change448. @)List three different classes of statisticaltechniques used to analyze and interpret research dataOnce the observations have been collected, they are often categorized anddescribed by descriptive statistical techniques. If a relationship betweendata has been hypothesized, correlational statistical techniques may beused to describe the extent to which two (or more) variables are related toeach other or for quantifying the degree of that relationship. Finally,inferential statistical techniques provide a set of procedures that allow theresearcher to infer that the events observed in the sample will also occurin the larger unobserved population from which the sample was obtained.449. @)What are the population and the sample in statistical terms?The population refers to any target group of things (animate or inanimate)in which there is interest. The population is the entire collection ofobservations or subjects that have something in common and to whichconclusions are inferred. A sample is a subset of the target population.Samples are taken because of the impossibility of observing the entirepopulation; it is generally not affordable, convenient, or practical to examinemore than a relatively small fraction of the population450. @)What is a "distribution"? Describe theNormal distribution.The group or set of all the observations of a variable along with the frequencyof their occurrence and placement of the values is called the distributionof the variable. A distribution may be based on empirical observationsor may be a theoretical probability distribution that is defined byan algebraic equation. The most important distribution is the Normaldistribution, also called the Gaussian or bell-curve distribution451. @)Why is the normal distribution so importantthe biological and medical research methods?The Normal distribution is important because it has been empiricallynoted that when a biologic variable is sampled repeatedly, the pattern ofthe numbers plotted as a histogram resembles the normal curve; thus,most biologic data are said to follow or to obey a normal distribution.Equally important, a mathematical theorem (the central limit theorem)allows the use of the assumption of Normality for certain purposes, even ifthe population is not Normally distributed452. @)List the three descriptive statistics thatspecify the central tendency, or middle, of numerical dataThe median is the center or middle data point if the data can be ordered(ranked) from smallest to largest. The median is the point at which halfthe observations are smaller, half are larger. The mode is the most frequentlyoccurring value. The mean is the arithmetic average of the numericalobservationsin a sample. The mean is symbolized by x-, called Xbar.453. ~On addition to describing the centraltendency of the data distribution, we alsoneed to characterize the spread or variabilityof a data sample. What two measures describethe spread or variability of data (hint: variability = deviation)?The spread, dispersion, or variability of data is described by the range andthe variance eo standard deviation. The range is simplest the differencebetween the largest and smallest observation. The standard deviation is ameasure of the spread of the data about their mean. The standard deviationmeasures the "average" spread of the observations about the mean.The variance is the square of the standard deviation and its mathematicalderivation and rationale is beyond the scope of this resource454. Inferential statistical techniques are eitherparametric or nonparametric. Define these termsWhen data follow a normal distribution, the methods of parametric statisticscan be used. The term parametric refers the ability to describe thedistribution with a specific set of values, or parameters. For the Normaldistribution, only two parameters are required to define and describe thedistribution: the mean and the standard deviation. If it is not possible todescribe the data with a set of parameters, nonparametric statistical methodsare required.455. @)What is the first question to ask in choosinga statistical test?The first question to ask in considering the choice of a statistical test is todecide whether statistical methods that assume a Normal distribution(parametric) are appropriate, or whether nonparametric methods areneeded (data is not Normally distributed456. ?What is the second question to ask inchoosing the appropriate statistical test?The second question to ask when choosing between statistical tests is"how many groups are being compared?" There may be one group, twogroups, or multiple groups to characterize457. ?What is the third question to ask in choosingthe appropriate statistical test, basedupon two or more groups?The third question to ask in choosing a statistical test is "are the data inthe groups paired or unpaired?" A key to answering this question is to ask"were the same individuals studied before and after some intervention orcondition?" If the answer is "yes, the same individuals were studied beforeand after an intervention" then these are paired data groups not independent groups458. ?Which statistical test compares the differencebetween the means of Normally distributedinterval or ratio data from two independent groupdThe unpaired (two-sample) Student's t test is used to compare the differencebetween the means of two independent groups, provided the observationsare Normally distributed interval measurements. [Nagelhout, NA.41h. 2009 pp58-59;459. @)Describe the appropriate application ofthe paired Student's t test.Given Normally distributed interval or ratio data, the paired t test (alsocalled a t test, dependent samples) evaluates the difference between dependent,paired sample (for example pretreatment and posttreatment)outcomes.460. @>Given nonparametric nominal data fromtwo or more independent samples (groups),which statistical test evaluates the differencebetween observed and expected frequencies?The Chi-squared analysis of contingency tables evaluates the differencebetween observed and expected frequencies from nominal or ordinal datathat are not necessarily Normally distributed. [Nagelhout, NA. 41h. 2009pp58-59; Miller, Miller's Anesthesia, 71h461. @>Which nonparametric test is the equivalentof the unpaired t test for nonparametric ordinal data?The Mann-Whitney rank sum test tells whether medians between twoindependent nonparametric groups of ordinal data are different. Afterindividual observations are ranked, the ranks are analyzed just as though .they were the original data. The various incarnations of the general ranksum test are often used by researches in the health field for nonparametricdata. [Nagelhout, NA. 41h.462. @>Which parametric test evaluates the differenceamong the means of interval or ratiodata from more than two independentgroups or more than one independent variable?An analysis of variance (ANOV A) tests the difference among the means ofmore than two independent groups or more than one independent variablegiven Normally distributed interval or ratio data463. >What is the appropriate statistical test todetermine whether one variable x (the independentvariable) predicts the outcome ofanother variable y (the dependent variable).Simple linear regression evaluates the association between two parametric,numeric variables. Linear regression produces an equation in the form ofy = mx + b that allows predication of the outcome variable y (the dependentvariable) given the predictor variable x (the independent variable).464. ?Define "standard of ca re."The standard of care is the conduct and skill of a prudent practitioner thatcan be expected by a reasonable patient. Standard of ca re is also definedas reasonable ca re by a professional. (Nagelhout). Standa rd of ca re is avery important medicolegal concept because a bad medical result due tofailu re to meet the standard of ca re is malpractice465. ,..-The National Practitioner Data Bank(NPDB) requires input (information) from what 5 sources?The National Practitioner Data Bank (NPDB) requires input from fivesources: (1) medical malpractice payments, (2) license actions by medicalboards, (3) professional review or clinical privilege actions taken by hospitalsand other health care entities (including professional societies), (4)actions taken by the Drug Enforcement Agency (DEA), and (5) Medicare/Medicaid exclusions.466. @)How is the standard of care established?What two sources are typically consulted toestablish the standard of care?Ultimately, the standard of care is what a jury says it is (Barash). Thereare two main sources of information as to exactly what is the expectedstandard of care. Traditionally, the beliefs offered by expert witnesses inmedical liability lawsuits regarding what is actually being done in real life(de facto standards of care) were the main input juries had in decidingwhat was reasonable to expect from the defendant. The second, muchmore objective, source for defining certain component parts of the standardof care is the published standards of care, guidelines, practice parameters,and protocols now becoming more common. These serve as hardevidence of what can be reasonably expected of practitioners and canmake it easier for a jury evaluating whether a malpractice defendant failedto meet the applicable standard of care467. @)What agency sets and enforces qualitystandards for ambulatory surgical facilities?Quality standards are set and enforced either by government regulation,through a licensing process, or by accreditation by private organizationssuch as the Accreditation Association for Ambulatory Health Care(AAAHC). The AAAHC is an independent accreditation organizationwhose principle activities are to develop standards. conduct surveys, andconfer accreditation on ambulatory health care providers. In the UnitedStates and Canada, hospital-based ambulatory surgical facilities receiveaccreditation through The Joint Commission (formerly JCAHO). [Miller,Miller's Anesthesia, 7th. 2009 pp2421)468. @)What are the first two actions to take inan ainvay fire? What are the next actions?The first action in an airway fire is to simultaneously stop ventilation andremove the endotracheal lube, followed immediately by turningoff/disconnecti'lg the oxygen. The sequence of subsequent actions varies(different references give slightly different orders) but includes: poursaline into airway; remove burning materials; mask ventilation and reintubation;diagnose the injury, treat by bronchoscopy and laryngoscopy;administer short-term steroids; monitor the patient for at least 24 hours;and. administer an tibiotics and provide ventilatory support as necessary ................
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