Vaso-Active Agents in the



Vaso-Active Agents in the Emergency Department

Michael C. Bond, MD

Objectives

1. Review the definition of SIRS and Shock

2. Review the different classifications of shock

3. Review vasopressors and their mechanisms of action

a. Dopamine

b. Dobutamine

c. Epinephrine

d. Norepinephrine

e. Phenylephrine

f. Vasopressin

4. Review the pathophysiology of septic shock and current treatment

Systemic Inflammatory Response Syndrome

1. Any two or more of the following are present

a. Heart rate > 90 beats per minute

b. Body temperature < 36 or > 38°C

c. Hyperventilation (high respiratory rate) > 20 breaths per minute or, on blood gas, a PaCO2 < 4.3 kPa (32 mm Hg)

d. White blood cell count < 4000 cells/mm3 or > 12000 cells/mm3 (< 4 x 109 or > 12 x 109 cells/L), or the presence of greater than 10% immature neutrophils.

Causes of SIRS

1. Severe trauma

2. Surgery, complication of

3. Burns

4. Acute pancreatitis

5. Immunodeficiency (such as AIDS)

6. Infection

SIRS versus Sepsis

SIRS with a confirmed infection, proven through a positive blood culture or tissue sample positive for pathogenic organisms, is called sepsis.

Shock Definition:

1. Inadequate tissue perfusion that impairs cellular metabolism

2. Oxygen Supply < Oxygen Demand

3. SBP 70%

2. If patient received adequate fluid resuscitation and CvO2 still 30%

b. Dobutamine therapy started

3. Patients improved in the EGT group

4. Rhodes A, Bennett ED. Early goal-directed therapy: An evidence-based review. Critical Care Medicine 2004; 32 (Suppl.):S448-S450.

a. Specific targets that should be reached during the first 6 hours of resuscitation are:

i. Central Venous Pressure (8-12 mm Hg)

ii. Mean Arterial Pressure ≥ 65 mm Hg

iii. Urine Output of ≥ 0.5 ml/kg/hr

iv. SvO2 ≥ 65% or ScO2 ≥ 70%

b. If these targets can not be reached you should

i. Transfuse packed red blood cells to achieve HCT ≥ 30%

ii. Administer dobutamine infusion (up to a maximum of 20 mcg/kg/min)

5. Trzeciak S, Dellinger RP, Abate NL. A 1-Year Experience with implementing Early Goal-Directed Therapy for Septic Shock in the Emergency Department. Chest 2006; 129:225-232.

a. All end points achieved in 20 of 22 cases

b. EGDT was associated with decreased ICU pulmonary artery catheter use (9.1% vs. 43.7%)

c. Volume Infused went from 3.5 L to 5.6 L in the ED, and 9L to 7.9 for first 24 hours.

Summary

1. Low dose dopamine should NOT be used for renal protection.

2. Norepinephrine has better outcomes than dopamine with no affect on dopamine receptors in the brain

3. Phenylephrine and Epinephrine should not be used as first line agents in septic shock.

4. Dobutamine is the agent of choice to increase cardiac output, and it should not be used to increase cardiac output above physiologic levels.

5. Vasopressin should be a second line agent due to the effects it might have on splanchnic blood flow.

References:

Reinelt H, Radermacher P, Kiefer P, Fischer G, Wachter U, Vogt J et al. Impact of exogenous beta-adrenergic receptor stimulation on hepatosplanchnic oxygen kinetics and metabolic activity in septic shock. Critical Care Medicine 1999; 27(2):325-331.

Comparison of dopamine to dobutamine and norepinephrine for oxygen delivery and uptake to septic shock. Critical Care Medicine 1995;23(12): 1962-1970

The contrasting effects of Dopamine and Norepinephrine on Systemic and Splanchnic Oxygen Utilization in Hyperdynamic Sepsis. JAMA 1994:272(17); 1354-1357.

Low Dose Dopamine: What Benefit? Critical Care Medicine 2000; 28 (3); 907-908.

Neviere R, Mathieu D, Chagnon JL, Lebleu N, Wattel F. The contrasting effects of dobutamine and dopamine on gastric mucosal perfusion in septic patients. Am J Respir Crit Care Med 1996; 154(6 Pt 1):1684-1688.

Kellum JA, Pinsky MR. Use of vasopressor agents in the critically ill patients. Current Opinion in Critical Care 2002; 8:236-241.

Holmes CL. Vasoactive drugs in the intensive care unit. Current Opinion in Critical Care 2005;11:413-417.

De Backer D, Creteur J, Silva E, et al. Effect of dopamine, norepinephrine, and epinephrine on the splanchnic circulation in septic shock: Which is best? Critical Care Medicine 2003; 31(6): 1659-1667.

Klinzing S, Simon M, Reinhart K, et al. High-dose vasopressin is not superior to norepinephrine in septic shock. Critical Care Medicine 2003; 31(11): 2646-2650.

Woolsey CA, Coopersmith CM. Vasoactive drugs and the gut: is there anything new? Current Opinion in Critical Care 2006; 12:155-159.

Van Haren FMP, Rozendaal FW, van der Hoeven JG. The effect of Vasopressin on Gastric Perfusion Catecholamine-Dependent Patients in Septic Shock. Chest 2004; 124:2256-2260.

Schleien CL, Osmond MH, Hickey R, et al. Postresusciatation Management. Ann Emerg Med. April 2001;37:S182-S195.

Dunser MW, Mayr AJ, Ulmer H, et al. Arginine Vasopressin in Advanced Vasodilitatory Shock, A Prospective, Randomized, Controlled Study. Circulation. 2003; 107:2313-2319.

Rhodes A, Bennett ED. Early goal-directed therapy: An evidence-based review. Critical Care Medicine 2004; 32 (Suppl.):S448-S450.

Trzeciak S, Dellinger RP, Abate NL. A 1-Year Experience with implementing Early Goal-Directed Therapy for Septic Shock in the Emergency Department. Chest 2006; 129:225-232.

Otero RM, Nguyen HB, Huang DT, Rivers EP, et al. Early Goal-Directed Therapy in Severe Sepsis and Septic Shock Revisted. Concepts, Controversies, and Contemporary Findings. Chest 2006; 130:1579-1595.

Herbert PC et al. A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. Transfusion Requirements in Critical Care Investigators, Canadian Critical Care Trials Group. NEJM. 349(6):409-417. 1999.

Marik PE, Sibbald WJ. Effects of stored-blood transfussion on oxygen delivery in patients with sepsis. JAMA 1993; 269:3024-3029.

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