Is single dose Dexamethasone effective in the prevention ...



Is single dose Dexamethasone effective in the prevention of laryngeal edema in adult surgical patients undergoing general anesthesia?April SchmidtDuke University School of NursingDecember 08, 2011Table of Contents Section of Paper PageIntroduction3Literature Review 3 Methodology7Design7Setting and Sample7Intervention8Variables8Instruments/Tools8Research Procedure9Informed Consent 11Strengths and Limitations11Timeline13Forms14References17 IntroductionDuring general anesthesia patients often require endotracheal intubation to facilitate control of ventilation. At the end of the procedure, ventilatory support is gradually weaned until the patient can breathe unaided and the endotracheal tube can be removed. Extubation is usually uneventful, but some patients experience irritation from the endotracheal tube or during the intubation itself leading to significant laryngeal edema. Laryngeal edema can lead to glottic or subglottic narrowing manifesting as stridor and dyspnea leading to respiratory failure and a need for reintubation. Reintubation is associated with a prolonged length of stay, intensive care admission, additional costs, and significantly higher morbidity and mortality (Jaber, Jung, Chanques, Bonnet, & Marret, 2009). Any intervention then, which decreases the risk of laryngeal edema and need for reintubation, is worth investigating.Anesthesia providers often give a steroid like Dexamethasone before extubation, in patients that are at increased risk for laryngeal edema. Multiple attempts at intubation or otherwise difficult airway establishment, surgery or procedures in or near the airway, and procedures which require the head down position all pose increased risk of upper airway edema. Other factors include female gender (probably due to a smaller airway size), trauma patients, an excessively large endotracheal tube, duration of intubation, and excess cuff pressure (Malhotra, Gurcoo, Qazi, & Gupta, 2009). The prevalence of stridor after extubation ranges from 6%-37% (Lee, Peng, & Wu, 2007).Despite the fact that many anesthesia providers use Dexamethasone and other steroids to prevent and treat laryngeal edema; its effectiveness is still controversial. The existing studies show inconclusive and conflicting results.Literature ReviewIn the research article, Dexamethasone to prevent postextubation airway obstruction in adults: a prospective, randomized, double-blind, placebo-controlled study, a RCT including 86 ICU patients who had been intubated for greater than 48 hours, were divided into 2 groups. The first group received Dexamethasone 5 mg IV every six hours for a total of four doses prior to extubation. The second group received a placebo. The results showed that incidence of postextubation stridor was significantly lower in the dexamethasone group (10%) versus the placebo group (27.5%), but there was no significant difference in reintubation rate between the two groups (Lee et al., 2007).Another RCT is discussed in the article, Randomized comparative efficacy of Dexamethasone to prevent postextubation upper airway complications in children and adults in ICU. This study included 120 patients half of which were adults and half of which were pediatrics. The patients were in the ICU and had been intubated greater than 24 hours. The pediatric and adult subjects were divided into two groups of even numbers of pediatric and adult subjects. One group received Dexamethasone (8mg for adults and 0.5 mg/kg for children every six hours for twenty-four hours). The second group received a placebo. The authors concluded that prophylactic use of intravenous dexamethasone is useful in preventing laryngeal edema postextubation in children but not adults (Malhotra et al., 2009).In, Commentary on evaluation of risk factors for laryngeal edema after tracheal extubation in adults and its prevention by dexamethasone [original article by Darmon J et al appears in ANESTHESIOLOGY 1992;77(2): 245-251], a RCT is discussed in which 700 adults in six ICUs, requiring tracheal intubation were stratified into two groups according to length of intubation (short duration <36 hours and long duration >36 hours). The patients were divided into two groups with one group receiving Dexamethasone 8 mg IV (one dose) prior to extubation and the second group received a placebo. Laryngeal edema (LE) was categorized as minor when dyspnea and/or stridor occurred and major when reintubation was required secondary to LE. The overall incidence of laryngeal edema was 4.2% and it was found to have occurred more frequently in those with a long duration intubation. 1% of all the patients required reintubation. There were no significant differences in the dexamethasone and placebo groups in regards to LE whether short or long term intubation (Brooks-Brunn, 1993). In the research article, Effects of Steroids on reintubation and post-extubation stridor in adults: meta-analysis of randomised controlled trials, a review of the literature of seven prospective, randomized, double-blinded trials including 1846 patients was analyzed and discussed. A quality assessment of the articles was performed and only articles with a score of three or greater were included. Studies were included with patients who had been mechanically ventilated for at least 24 hours and treated with steroids before extubation. The timing of the steroid administration (early vs late) and if the population selected was at risk or not was taken into account. Trials were included that divided the study groups into two: one receiving steroids and the other receiving placebo. Overall, it was found that steroids significantly decreased the risk of stridor and reintubation. The effect of steroids on stridor and reintubation was more pronounced in the selected high risk patients. Steroid benefit was unclear when trials did not select patients based on their risk of reintubation need. It was also noted that steroids were of more benefit when they were administered at least four hours before extubation (Jaber et al., 2009).Another meta-analysis, Prophylactic administration of parenteral steroids for preventing airway complications after extubation in adults: meta-analysis of randomised placebo controlled trials, was reviewed. In this meta-analysis, six RCTs including a total of 1923 patients were analyzed. The subjects in each of the studies were patients who had been tracheally intubated for at least 24 hours. They were divided into two groups, one of which received steroids (steroids used and doses given varied amongst the studies) and the other received a placebo. Postextubation, minor LE was defined as stridor and dyspnea and major LE was defined as severe respiratory distress requiring tracheal reintubation secondary to upper airway obstruction. The findings of the trials were divided so that those that received multiple doses of steroids were separated from those that received single doses. After analysis of all six RCTS, the authors found evidence showing that compared with placebo, a multi-dose regimen of steroids prior to extubation was effective in reducing the occurrence of laryngeal edema and on the occurrence of subsequent reintubation. A subgroup analysis showed that the single-dose steroid regimen only showed a trend toward the benefits (Fan et al., 2008). After a review of the existing literature, it is evident that more studies are needed to answer the research question, “Is single dose Dexamethasone effective in the prevention of laryngeal edema in adult surgical patients undergoing general anesthesia?” The existing studies mostly focus on patients who are in the ICU setting and have been intubated greater than 24 hours. Therefore, information from these studies cannot be extrapolated to surgical patients in the O.R. setting who are intubated for less than 24 hours. Many of the studies were based on multi-doses of steroids for up to 24 hours before planned extubation and this is not feasible in the O.R. setting. Also, many studies are done on the use of “steroids” and not specifically Dexamethasone which has a rapid onset of action unlike many other steroids. There are many shortcomings of the existing literature. Further studies are needed that are more applicable to the short-term intubation of surgical patients undergoing general anesthesia in which there is often only enough time to administer one dose of Dexamethasone. Many anesthesia providers routinely administer Dexamethasone to patients they feel are at increased risk of laryngeal edema, but studies to support its ability to prevent laryngeal edema and subsequent need for reintubation are lacking. The purpose of this proposed study is to determine whether single dose Dexamethasone given in the O.R. setting prior to extubation in patients at high risk for laryngeal edema is effective in the prevention of that edema and need for subsequent reintubation. MethodsDesignThis research study will use a randomized control design. The subjects will be divided randomly into either the control group or the experimental group by the use of a table of random numbers. The first group, the control group, will receive a placebo of normal saline IV. The second group, the experimental group, will receive the experimental treatment which will be Dexamethasone 8 mg IV just after intubation. This study will test the hypothesis that a single dose of intravenous Dexamethasone is effective in the prevention of laryngeal edema in surgical patients undergoing general anesthesia who are deemed to be at high risk for laryngeal edema. Setting and SampleThis study will be conducted at Carolinaeast Medical Center in the operating room by the anesthesia team. Study participants will be obtained using inclusion and exclusion criteria. Researchers in conjunction with the anesthesia team will review the patients’ charts preoperatively for potential inclusion into the study. Inclusion criteria will consist of patients whom are undergoing general anesthesia with endotracheal intubation, those with a past history of difficult airway, patients who will be undergoing surgery of the head and neck region, patients with evidence of head, neck, or airway edema present preoperatively, any patient who requires more than one attempt at establishing endotracheal tube placement, any patient who will be in a head down position for the majority of the surgery, and patients 18 years of age or older. Exclusion criteria would be any patient who has an allergy to Dexamethasone, any patient who is on a current regimen of steroids who may require a larger dose or different steroid intraoperatively, or any patient who has uncontrolled diabetes mellitus (preoperative blood glucose >250mg/dL). A checklist of inclusion and exclusion criteria will be placed on every surgical patients chart to facilitate ease of subject selection. Power analysis will be performed by a trained statistician to determine an adequate sample size. InterventionThe intervention will consist of any patient in the experimental group who meets the inclusion criteria receiving Dexamethasone 8 mg IV within 10 minutes after intubation. The length of time from administration of the Dexamethasone to extubation will be documented. VariablesThe independent variable in this study will be the administration of Dexamethasone to the subjects in the experimental group. The dependent variables will be the development of laryngeal edema as evidenced by stridor and/or dyspnea and the development of need for reintubation due to respiratory distress related to laryngeal edema. The demographic variables that will be measured are age, gender, surgical procedure performed, Mallampati airway class, and any co-morbidities that may predispose the patient to airway compromise. Instruments/ToolsThree forms will be used to facilitate the collection of information needed for the study. These will include the “Demographic” form, “Inclusion/Exclusion Criteria” form, and the “Post-Extubation Findings” form. A copy of each form is attached.Research ProcedureThe research team will apply for external funding. This research proposal will be submitted to Carolinaeast Medical Center’s IRB for approval. Once the funding is received and the proposal has met approval by the IRB, two research assistants will be trained. Training will include how to obtain proper informed consent, ensuring understanding of the guidelines for inclusion and exclusion criteria and how to use the inclusion/exclusion form, and educating them on how to categorize and record the results for each subject using a results form. A meeting will take place with the members of the anesthesia team as well as the post-anesthesia care unit nurses for training as well. All members of the research team will be informed of and expected to uphold HIPPA guidelines. Anyone who will be involved in the research that does not have a signed form on file stating that they understand and will comply with HIPPA guidelines should do so at this time. The data collection portion of the study will take place over the course of 6 months. The sample size will be determined by the power analysis performed by the statistician. The number of subjects will be divided evenly and randomly assigned to one of the two groups by using a table of random numbers. Next, an inclusion/exclusion form will be filled out on all patients in the preoperative holding area who are age 18 years old or older and legally able to give their own consent. All of these patients with the exception of those meeting exclusion criteria will be informed of the study by a member of the trained research team prior to the patient receiving any anxiolytics or drugs causing sedation. The research team member should answer all the patient’s questions to their satisfaction. If the patient is in agreement with study participation, a consent form should be signed by the patient. The patients should be informed that the information collected will be used for research purposes only and that demographical and personal information will not be released. Once informed consent is obtained, the chart/pre-anesthesia record will be reviewed to obtain demographic data to be recorded on the demographic data form. At this point, the patient would be assigned to either the experimental or control group based on the table of random numbers in case they will be included in the study. It may not be determined which patients will actually be included in the study until after intubation because one of the inclusion criterion is multiple attempts at intubation and this will not be known until that point. 3 ml syringes filled with 2 ml of either Dexamethasone (8mg) or normal saline will be prepared ahead of time and it will not be identified to the researcher or anesthesia team member which is being administered. Administration of either the Dexamethasone or normal saline (based on which group the patient is assigned to) will occur within 10 minutes after intubation if the patient met inclusion/exclusion criteria.Once the patient is extubated, they will be observed by the anesthesia provider until transport and hand off to the PACU nurse at which time they will be observed by the PACU nurse. Once the patient is ready to be discharged, the PACU nurse will fill out the “Post-Extubation Findings” form which includes 3 categories of findings. “Category #1” is to be marked for patients who experienced no stridor, dyspnea, severe respiratory distress, or need for reintubation. “Category #2” is to be marked for patients who experienced stridor and/or dyspnea but did not require reintubation. “Category #3” is to be marked for patients who did experience severe respiratory distress requiring reintubation. There is also an optional “Comments” section where information can be added to determine if reintubation was due to a cause other than laryngeal edema. For example, if the patients muscle relaxant had not completely worn off or was not completely reversed and the patient exhibited signs of weakness this information would be written in the “Comments” section. At the end of the trial period, all the data will be collected from the forms and all patient identifiers would be removed to comply with HIPPA regulations. The subjects would be identified only by a four-digit number. The data would then be sent to an analysis team which would consist of two professional statisticians. After informing the team of the study’s purpose and the design used, they would analyze the data. Data relationships and statistical significance would be determined by the analysis team. Informed Consent All potential subjects must sign an informed consent in order to take part in the study. The consent form will be in plain words on an eighth grade reading level or less. A member of the research team will explain the intervention to be done, purpose of the study, risks and benefits of the study, length of the study, and any costs associated with the study. The subjects will be informed that their participation is strictly voluntary and that their confidentiality will be maintained. Time will be allotted to thoroughly answer all of the potential subjects’ questions. The person witnessing the consent signature will also sign the form. The patient will be given a copy of the consent with the names of the researchers and information on how to contact them with questions. A copy of the signed consent will be kept on file.Strengths and LimitationsThe strengths of this study are that it provides for randomization, control, and manipulation as required by a true randomized control trial (RCT). Randomization is achieved by the use of a table of random numbers for assignment to the control group or the experimental group. The use of a control group which receives a placebo provides for control. Manipulation is achieved by the administration of the experimental regimen which is Dexamethasone 8 mg IV. Using power analysis helps to ensure an adequate sample size and controls for type II error.The limitations of the study are that the tool for recording post-extubation results leaves some room for subjectivity. There will be many anesthesia providers involved in this study which may lead to some study bias. Also, having to wait until patients are intubated to determine if they will be included in the study is inconvenient. The period of induction of anesthesia through surgical incision is a very busy time and some patients may be excluded due to inability to administer the Dexamethasone or placebo within the 10 minute time frame. TimelineJanuary 2012Submit proposal to CEMC IRBApply for external fundingApril 2012Obtain study approval by IRBJune 2012Obtain fundingJuly 2012Obtain and train research assistants Meet with and train anesthesia team Meet with and train PACU nursesAugust 2012Begin studyDecember 2012Recruit and train data analysis teamFebruary 2013Study data collection endsMarch 2013Submit data for analysisJune 2013Receive results Begin writing reportDecember 2013Publication of studyDemographic DataAge:Gender:Mallampati Class:Surgical Procedure performed:Co-morbidities that may contribute to upper airway edema:Inclusion/Exclusion ToolDirections: Fill in the circle under yes or no that indicates the correct response to each question. Yes NoIs the patient 18 yrs old or older? O O Did the patient have general anesthesia with endotracheal tube placement? O ODoes the patient have a past history of a difficult airway? O ODid the patient undergo surgery of the head and/or neck?O OWas there any head/neck/airway edema noted preoperatively?O ODid the patient require one than one attempt to intubate the airway?O O Was the patient in the head down position during the majority of the surgery?O OPost-Extubation FindingsDirections: Fill in the circle beside the category that best describes this patient. Only fill in one circle. Then answer the question that follows by filling in the circle under the “Yes” or “No”. Use the “Comments” section to describe any factors that may have influenced the need for reintubation. OCategory #1 Patients who experienced no stridor, dyspnea, severe respiratory distress, or need for reintubationOCategory #2 Patients who experienced stridor and/or dyspnea but did not require reintubation OCategory #3 Patients who experienced severe respiratory distress requiring reintubationWas the length of time between intubation and administration of the drug/placebo within 10 minutes?Yes NoO OComments: ReferencesBrooks-Brunn, J. A. (1993, Jan-Feb). Commentary on evaluation of risk factors for laryngeal edema after tracheal extubation in adults and its prevention by Dexamethasone. AACN Nursing Scan in Critical Care, 3, 5-6.Darmon, J., Rauss, A., Dreyfuss, D., Bleichner, G., Elkharrat, D., Schlemmer, B.,...Huet, Y. (1992). Evaluation of risk factors for laryngeal edema after tracheal extubation in adults and its prevention by dexamethasone. Anesthesiology, 77, 245-251.Fan, T., Wang, G., Mao, B., Xiong, Z., Zhang, Y., Liu, X.,...Yang, S. (2008). Prophylacitc administration of parenteral steroids for preventing airway complications after extubation in adults: meta-analysis of randomised placebo controlled trials. BMJ, 33Jaber, S., Jung, B., Chanques, G., Bonnet, F., & Marret, E. (2009). Effects of steroids on reintubation and post-extubation stridor in adults: meta-analysis of randomised controlled trials. Critical Care, 13.Lee, C., Peng, M., & Wu, C. (2007). Dexamethasone to prevent postextubation airway obstruction in adults: a prospective, randomized, double-blind, placebo-controlled study. Critical Care, 11(4).Malhotra, D., Gurcoo, S., Qazi, S., & Gupta, S. (2009, August). Randomized comparative efficacy of Dexamethasone to prevent postextubation upper airway complications in children and adults in ICU. Indian Journal of Anaesthesia, 53, 442-449. ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download