The safety of etomidate for emergency rapid sequence intubation of pediatric patients

Etomidate and its Analogs: A Review of Pharmacokinetics and Pharmacodynamics

Etomidate is a hypnotic agent that is used for the induction of anesthesia. It produces its effect by acting as a positive allosteric modulator on the γ-aminobutyric acid type A receptor and thus enhancing the effect of the inhibitory neurotransmitter γ-aminobutyric acid. Etomidate stands out among other anesthetic agents by having a remarkably stable cardiorespiratory profile, producing no cardiovascular or respiratory depression. However, etomidate suppresses the adrenocortical axis by the inhibition of the enzyme 11β-hydroxylase. This makes the drug unsuitable for administration by a prolonged infusion. It also makes the drug unsuitable for administration to critically ill patients. Etomidate has relatively large volumes of distributions and is rapidly metabolized by hepatic esterases into an inactive carboxylic acid through hydrolyzation. Because of the decrease in popularity of etomidate, few modern extensive pharmacokinetic or pharmacodynamic studies exist. Over the last decade, several analogs of etomidate have been developed, with the aim of retaining its stable cardiorespiratory profile, whilst eliminating its suppressive effect on the adrenocortical axis. One of these molecules, ABP-700, was studied in extensive phase I clinical trials. These found that ABP-700 is characterized by small volumes of distribution and rapid clearance. ABP-700 is metabolized similarly to etomidate, by hydrolyzation into an inactive carboxylic acid. Furthermore, ABP-700 showed a rapid onset and offset of clinical effect. One side effect observed with both etomidate and ABP-700 is the occurrence of involuntary muscle movements. The origin of these movements is unclear and warrants further research.

Continuous-Infusion Etomidate in a Patient Receiving Extracorporeal Membrane Oxygenation

We describe a 16-year-old, 65-kg male deployed on extracorporeal membrane oxygenation (ECMO) for refractory respiratory failure secondary to ingestion of multiple substances. During his ECMO course, standard sedative and analgesic strategies failed and alternative medications were used. The patient received various dosages of fentanyl, morphine, hydromorphone, clonidine patches, dexmedetomidine, lorazepam, methadone, pentobarbital, olanzapine, and propofol. Despite administration of multiple agents, on day 29 of ECMO the patient experienced elevated blood pressures due to agitation, and continuous infusion etomidate was started. At the time of etomidate initiation, the osmolar gap was 8 mOsm/kg. During etomidate therapy, the blood pressure remained normal, sedative agents were slowly weaned, and the patient required few PRN medications. On day 6 of etomidate, the osmolar gap increased to 127 mOsm/kg and etomidate was discontinued. Continuous-infusion ketamine was started, but the blood pressure was not controlled. Metabolic acidosis is a known side effect of etomidate due to inclusion of propylene glycol as a pharmaceutical solvent in the formulation. Despite high-dose etomidate (20 mcg/kg/min) for approximately 6 days, our patient did not experience metabolic acidosis. Absence of this adverse effect caused us to question the role of the ECMO circuit. To our knowledge, this is the first report of the use of continuous-infusion etomidate during ECMO. Etomidate infusion could be considered in difficult-to-manage patients after other alternatives have failed.

Emergency induction of anaesthesia in the prehospital setting: a review of the anaesthetic induction agents

The standard of prehospital care is improving in many trauma systems around the world. For patients surviving the primary injury, the optimal prehospital interven tions remain debatable. Current evidence suggests that patients with severe head injury may benefit from advanced airway management, most commonly per formed by rapid sequence induction of anaesthesia and orotracheal intubation. The ‘best choice’ induction agent remains unclear, and choice seems to depend on local preferences and the skill mix of the prehospital care team. In this review we look at the recent evidence for selected hypnotic agents.

Conscious Intravenous Sedation in Dentistry: A Review of Current Therapy

Several sedation options are used to minimize pain, anxiety, and discomfort during oral surgery procedures. Minimizing or eliminating pain and anxiety for dental care is the primary goal for conscious sedation. Intravenous conscious sedation is a drug-induced depression of consciousness during which patients respond purposefully to verbal commands. No interventions are required to maintain a patent airway, and spontaneous ventilation is adequate as well as cardiovascular function. Patients must retain their protective airway reflexes, and respond to and understand verbal communication. The drugs and techniques used must therefore carry a broad margin of safety.

Etomidate in pediatric anesthesiology: Where are we now?

Etomidate is an intravenous anesthetic agent released for clinical use in the United States in 1972. Its popularity in clinical practice is the result of its beneficial effects on intracerebral dynamics with limited effects on hemodynamic function. These properties have made it a safe and effective anesthetic induction agent in both adult and pediatric patients with altered myocardial performance, congenial heart disease, or hypovolemia. However, recent concern has been expressed regarding its effects on the endogenous production of corticosteroids and the impact of that effect on patient outcomes. The following manuscript reviews clinical reports regarding etomidate use in the pediatric population and discusses recent concerns regarding its effects on corticosteroid metabolism and the implications of such effects for clinical use.

Is propofol an optimal agent for procedural sedation and rapid sequence intubation in the emergency department?

Objective:

We conducted a qualitative systematic review to evaluate the efficacy and safety of propofol for direct current cardioversion (DCC), rapid sequence intubation (RSI) and procedural sedation in adult emergency department (ED) patients.

Data source:

MEDLINE (1966 to September 2000), PubMed (to September 2000), EMBASE (1988 to September 2000), Database of Systematic Reviews (to September 2000), Best Evidence (1991 to September 2000) and Current Contents (1996 to September 2000) databases.

Study selection:

English-language, randomized, comparative evaluations of propofol for procedures routinely conducted in adults (>18 years) were included. Direct current cardioversion, RSI and procedural sedation were considered.

Data extraction:

Efficacy and safety endpoints were evaluated for all trials. For DCC and procedural sedation trials, efficacy measures included induction and recovery times, as well as the association for successful procedure. For the RSI trials, optimal intubating conditions were evaluated as the primary efficacy endpoint. Safety measures included hemodynamic changes, apnea rates and adverse effects.

Data synthesis:

In the setting of DCC, efficacy and safety outcomes were similar for propofol, thiopental, etomidate and methohexital. All of these agents provided markedly shorter induction and recovery times than midazolam. Patients who were pre-medicated with fentanyl exhibited prolonged recovery times and greater decreases in blood pressure. When used for RSI, propofol administration was associated with satisfactory intubating conditions that were comparable to those seen with thiopental and etomidate. Blood pressure reductions were seen in both DCC and RSI studies. Apneic episodes (>30 seconds) occurred in 23% of propofol recipients, 28% of thiopental recipients and 7% of etomidate and midazolam recipients. Apart from the DCC studies described, no procedural sedation studies met our predefined review eligibility criteria.

Conclusion:

The body of literature evaluating propofol for DCC and RSI in the ED is limited. There is evidence to support the use of propofol for DCC and RSI, but this evidence comes from stable patients in non-ED settings. Further ED-based randomized comparative trials should be conducted before propofol is adopted for widespread use in the ED.

Anesthesia for stem cell transplantation in autistic children: A prospective, randomized, double-blind comparison of propofol and etomidate following sevoflurane inhalation

The objective of the present study was to comparatively investigate the feasibility and safety of etomidate and propofol use following sevoflurane inhalation in autistic children during the intrathecal transplantation of stem cells. The patients selected were 60 autistic children with American Society of Anesthesiologists physical status I, who were aged between two and 12 years and scheduled for stem cell transplantation. The children received an inhalation induction of 8% sevoflurane, followed by intravenous injection of etomidate (0.2 mg/kg) in group E and propofol (2 mg/kg) in group P (n=30/group). Supplemental doses of 0.1 mg/kg etomidate or 1 mg/kg propofol were used until a deep sedation was obtained. The heart rate (HR), mean arterial pressure, oxygen saturation, respiratory rate, Ramsay sedation score (RSS) and recovery time were monitored continuously. Following anesthesia, blood pressure and HR measurements were significantly decreased in group P compared with the baseline (P<0.01) and group E values at the same time-points (P<0.05). The occurrence of adverse effects, such as respiratory depression, bradycardia, hypotension and pain on injection, was significantly higher in group P than that in group E, whereas the incidence of myoclonus in group E was significantly higher than that in group P (P<0.01). No significant differences in anesthesia induction, surgery duration, recovery time, RSS and physician satisfaction were observed between the two groups. In conclusion, sevoflurane-etomidate combinations resulted in more stable hemodynamic responses and relatively fewer adverse effects compared with propofol injection following sevoflurane inhalation and may therefore be more suitable for the induction of short-term anesthesia in autistic children during stem cell transplantation.

Pediatric critical care

Care of the ill and injured child requires knowledge of unique pediatric anatomic and physiologic differences. Subtleties in presentation and pathophysiologic differences impact management. This article discusses pediatric resuscitation, the presentation and management of common childhood illness, pediatric trauma, and common procedures required in the critically ill child.

Etomidate, adrenal function, and mortality in critically ill patients

BACKGROUND

In critically ill patients, induction with etomidate is hypothesized to be associated with an increased risk of mortality. Previous randomized studies suggest a modest trend toward an increased risk of death among etomidate recipients; however, this relationship has not been measured with great statistical precision. We aimed to test whether etomidate is associated with risk of hospital mortality and other clinical outcomes in critically ill patients.

METHODS

We conducted a retrospective cohort study from January 1, 2001, to December 31, 2005, of 824 subjects requiring mechanical ventilation, who underwent adrenal function testing in the ICUs of 2 academic medical centers. The primary outcome was in-hospital mortality, comparing subjects given etomidate (n = 452) to those given an alternative induction agent (n = 372). The secondary outcome was diagnosis of critical illness-related corticosteroid insufficiency following etomidate exposure.

RESULTS

Overall mortality was 34.3%. After adjustment for age, sex, and baseline illness severity, the relative risk of death among the etomidate recipients was higher than that of subjects given an alternative agent (relative risk 1.20, 95% CI 0.99-1.45). Among subjects whose adrenal function was assessed within the 48 hours following intubation, the adjusted risk of meeting the criteria for critical illness-related corticosteroid insufficiency was 1.37 (95% CI 1.12-1.66), comparing etomidate recipients to subjects given another induction agent.

CONCLUSIONS

In this study of critically ill patients requiring endotracheal intubation, etomidate administration was associated with a trend toward a relative increase in mortality, similar to the collective results of smaller randomized trials conducted to date. If a small relative increased risk is truly present, though previous trials have been underpowered to detect it, in absolute terms the number of deaths associated with etomidate in this high-risk population would be considerable. Large, prospective controlled trials are needed to finalize the role of etomidate in critically ill patients.

Pro-con debate: etomidate or ketamine for rapid sequence intubation in pediatric patients

When caring for critically ill children, airway management remains a primary determinant of the eventual outcome. Airway control with endotracheal intubation is frequently necessary. Rapid sequence intubation (RSI) is generally used in emergency airway management to protect the airway from passive regurgitation of gastric contents. Along with a rapid acting neuromuscular blocking agent, sedation is an essential element of RSI. A significant safety concern regarding sedatives is the risk of hypotension and cardiovascular collapse, especially in critically ill patients or those with pre-existing comorbid conditions. Ketamine and etomidate, both of which provide effective sedation with limited effects on hemodynamic function, have become increasingly popular as induction agents for RSI. However, experience and clinical investigations have raised safety concerns associated with both etomidate and ketamine. Using a pro-con debate style, the following manuscript discusses the use of ketamine versus etomidate in RSI.

A review of etomidate for rapid sequence intubation in the emergency department

Etomidate is a sedative-hypnotic chemically unrelated to other induction agents. The pharmacological and safety profile of etomidate offers many advantages for induction during rapid sequence intubation (RSI) in the emergency department (ED). Its onset of action is within 5 to 15 seconds, and its duration of action is 5 to 15 minutes. Unlike thiopental, propofol, midazolam and, to a lesser extent, ketamine, etomidate has minimal respiratory or cardiovascular effects and can be safely used in patients with hemodynamic instability or cardiac ischemia. Etomidate is cerebroprotective, with the ability to decrease intracranial pressure and maintain cerebral perfusion, making it an ideal agent for patients with head injuries. Of the currently available induction agents, etomidate offers the most favourable safety profile and is the least likely to produce adverse effects in patients with unknown or untreated medical conditions. Etomidate may cause pain on injection, myoclonic movements on induction, hiccups, nausea and vomiting. Transient adrenal suppression has been reported, but not to a clinically significant degree, after single induction doses for ED RSI. Etomidate has been well studied in the ED and should be adopted for RSI in specific ED patient groups.

Etomidate for short pediatric procedures in the emergency department

OBJECTIVE

This study aimed to prospectively determine the etomidate dose associated with adequate sedation and few significant respiratory events for procedures of short duration in children.

METHODS

This is a prospective cohort study in an urban pediatric emergency department of patients 4 to 18 years requiring sedation and analgesia for painful procedures of short duration. Patients received fentanyl 1 μg/kg followed by intravenously administered etomidate 0.1 to 0.2 mg/kg as a loading dose. An additional dose of etomidate 0.1 mg/kg was intravenously administered if needed. The level of sedation was determined by The Children's Hospital of Wisconsin Sedation Score. The primary outcome was to determine the etomidate dose associated with an adequate level of sedation and procedural completion.

RESULTS

Sixty patients were enrolled. The most frequent procedure was fracture reduction (50/60, 83.3%). Procedures were successfully completed for 59 (98.3%) of 60 patients. The initial dose of etomidate associated with adequate sedation was 0.2 mg/kg intravenously administered for 33 (66.7%) of 50 patients requiring fracture reduction and for 6 (60.0%) of 10 patients receiving a procedure other than fracture reduction. Respiratory depression was noted in 9 (16.4%) of 55 patients, and oxygen desaturation was noted in 23 (39.0%) of 59 patients. Of 58 patients, 21 (36.2%) experienced a respiratory adverse event requiring brief intervention including oxygen supplementation, stimulation, and/or airway repositioning. No patient experienced a significant adverse respiratory event, defined as positive pressure ventilation. Median time to discharge-ready was 21 minutes.

CONCLUSIONS

For short-duration painful emergency department procedures, etomidate 0.2 mg/kg intravenously administered after fentanyl was associated with effective sedation, successful procedural completion, and readily managed respiratory adverse events in children.

Cardiac arrest following ketamine administration for rapid sequence intubation

Given their relative hemodynamic stability, ketamine and etomidate are commonly chosen anesthetic agents for sedation during the endotracheal intubation of critically ill patients. As the use of etomidate has come into question particularly in patients with sepsis, due to its effect of adrenal suppression, there has been a shift in practice with more reliance on ketamine. However, as ketamine relies on a secondary sympathomimetic effect for its cardiovascular stability, cardiovascular and hemodynamic compromise may occur in patients who are catecholamine depleted. We present 2 critically ill patients who experienced cardiac arrest following the administration of ketamine for rapid sequence intubation (RSI). The literature regarding the use of etomidate and ketamine for RSI in critically ill patients is reviewed and options for sedation during endotracheal intubation in this population are discussed.

Single-dose etomidate for intubation in the trauma patient

BACKGROUND

Concerns over adrenal suppression caused by a single dose of etomidate for intubation led to limiting its use in trauma patients in 2006.

OBJECTIVE

The purpose of this study was to compare mortality, hypotension, and intensive care unit (ICU) and hospital length of stay (LOS) for trauma patients requiring intubation during periods of liberal vs. limited etomidate use.

METHODS

A retrospective review of trauma patients requiring emergent intubation who presented between August 2004 and December 2008, before and after we decided to limit the use of etomidate. Data were collected on patient demographics, induction agents used, episodes of hypotension in the first 24h, ICU and total hospital LOS, and survival.

RESULTS

Of 1325 trauma patients intubated in the Emergency Department during the study period, 443 occurred during the 23 months before July 2006 (liberal etomidate use) and 882 in the 30 months after July 2006 (limited etomidate use). During the liberal use period, 258/443 (58%) were intubated using etomidate, compared to 205/882 (23%, p<0.0001) during the period of limited use. We found no significant differences in mortality (30% vs. 29%, p=0.70), mean ICU days (8.2 vs. 8.8, p=0.356), or mean hospital LOS (13.8 vs. 14.4 days, p=0.55). Episodes of hypotension were more common in the limited etomidate use group (45% vs. 33%, p<0.0001).

CONCLUSIONS

A significant reduction in the use of etomidate in trauma patients was not associated with differences in mortality, ICU days, or hospital LOS, but was associated with an increase in episodes of hypotension within 24h of presentation.

Population pharmacokinetics of intravenous bolus etomidate in children over 6 months of age

BACKGROUND

Information has been very limited on the population pharmacokinetics (PK) of etomidate in pediatric patients. The purpose of this study was to characterize the PK of etomidate in children.

METHODS

Forty-nine children aged over 6 months undergoing elective surgery received etomidate 0.3 mg·kg(-1) bolus i.v. within 15 s for anesthesia induction. Arterial blood samples were collected for 2 h after injection. A population nonlinear mixed effects modeling approach was used to characterize etomidate PK. Estimates were standardized to a 70-kg adult using allometric size models.

RESULTS

Children had a median age of 4 years (0.53-13.21 years) and weight 15.7 kg (7.5-52 kg). PK of etomidate was best estimated using a three-compartment model with weight on systemic (Cl(1)) and inter-compartmental clearances (Cl(2), Cl(3)), central (V(1)), and peripheral compartment volumes (V(2), V(3)). The most significant PK covariate was age, with increasing age having reduced size-adjusted Cl(1), V(1), and V(3) (all P < 0.01). The estimates of PK parameter (standardized to 70-kg adult) for a typical 4-year-old children were Cl(1) = 1.50 l·min(-1), Cl(2) = 1.95 l·min(-1), Cl(3) = 1.23 l·min(-1), V(1) = 9.51 l, V(2) = 11.0 l, and V(3) = 79.2 l, respectively.

CONCLUSIONS

Owing to enhanced clearance and increased central compartment volume of etomidate, smaller (younger) children will require higher etomidate bolus dose than larger (older) children to achieve equivalent plasma concentrations. The dependence of Cl(1) and V(1) on age does not support weight-based etomidate dosing in smaller children.

Differential effects of etomidate and its pyrrole analogue carboetomidate on the adrenocortical and cytokine responses to endotoxemia

OBJECTIVE

We developed a novel pyrrole analog of etomidate, (R)-ethyl 1-(1-phenylethyl)-1H-pyrrole-2-carboxylate (carboetomidate), which retains etomidate's desirable anesthetic and hemodynamic properties but lacks its potent inhibitory affect on adrenocorticotropic hormone-stimulated steroid synthesis. The objective of this study was to test the hypothesis that in contrast to etomidate, carboetomidate neither suppresses the adrenocortical response to endotoxemia nor enhances the accompanying production of proinflammatory cytokines.

DESIGN

Animal study.

SETTING

University research laboratory.

SUBJECTS

Male Sprague-Dawley rats.

INTERVENTIONS

For both single and multiple anesthetic dose studies, rats were injected with Escherichia coli lipopolysaccharide immediately followed by a hypnotic dose of etomidate, carboetomidate, or vehicle alone (dimethyl sulfoxide) as a control. For single-dose studies, no additional anesthetic (or vehicle) was administered. For multiple anesthetic dose studies, additional doses of anesthetic (or vehicle) were administered every 15 mins for a total of eight anesthetic (or vehicle) doses.

MEASUREMENTS AND MAIN RESULTS

Plasma adrenocorticotropic hormone, corticosterone, and cytokine concentrations were measured before lipopolysaccharide administration and intermittently throughout the 5-hr experiment. In single anesthetic dose studies, plasma adrenocorticotropic hormone and cytokine concentrations were not different at any time point among the etomidate, carboetomidate, and vehicle groups, whereas plasma corticosterone concentrations were briefly (60-120 mins) reduced in the etomidate group. In multiple anesthetic dose studies, plasma corticosterone concentrations were persistently lower and peak plasma interleukin-1β and interleukin-6 concentrations were higher in the etomidate group vs. the carboetomidate and control groups. Peak plasma interleukin-10 concentrations were similarly elevated in the etomidate and carboetomidate groups vs. the control group.

CONCLUSIONS

Compared with etomidate, carboetomidate produces less suppression of adrenocortical function and smaller increases in proinflammatory cytokine production in an endotoxemia model of sepsis. These findings suggest that carboetomidate could be a useful alternative to etomidate for maintaining anesthesia for a prolonged period of time in patients with sepsis.

Emergency tracheal intubation of severely head-injured children: changing daily practice after implementation of national guidelines

OBJECTIVE

To report daily practice of scene emergency tracheal intubation performed by physicians and changes induced by implementation of national guidelines, with special attention to rapid sequence induction (RSI) and control of assisted ventilation.

DESIGN

Observational study.

SETTING

Pediatric intensive care unit of a university hospital.

PATIENTS

A total of 296 children (age, 2-15 yrs old) referred to our center for severe traumatic brain injury (Glasgow Coma Scale score of ≤ 8), with spontaneous cardiac rhythm.

INTERVENTIONS

Scene RSI practice by field physicians was compared before (n = 188), and after (n = 108) publication of national guidelines. Emergency tracheal intubation conditions, RSI use, immediate complications, assisted ventilation efficiency on blood gases measurements upon arrival, and, in the later period, physician's knowledge, and observance to published guidelines were analyzed.

MEASUREMENTS AND MAIN RESULTS

After publication of guidelines, tracheal intubation was performed at the scene in 100% of the cases (vs. 88%, p = .05); RSI practice was more standardized, with an increased use of succinylcholine (10% to 80%, p = .0001), and a concomitant decreased use of nondepolarizing muscle relaxant (20% vs. 0%, p = .005), and opioids (70% vs. 36%, p = .05). Recommended RSI protocol (etomidate and succinylcholine) was effectively used by 64% of the physicians (vs. 2.8%, p = .001), and rate of immediate complications upon tube insertion (mainly cough reflex) decreased to 8% (vs. 25%, p = .0015). Scene emergency tracheal intubation, when ordered, resulted in a 100% success rate and adequate oxygenation within the two groups. Despite increasing the use of portable capnograph in the later period, Paco2 was measured outside the tight target range (35-40 torr, 4.6-5.3 kPa) in 70% of the cases upon arrival.

CONCLUSIONS

Scene emergency tracheal intubation was effectively performed by trained careproviders in children with traumatic brain injury. Implementation of guidelines led to a more standardized practice of RSI, decreased rate of immediate complications, but insufficient control of Paco2 during transport.

Part 10: Pediatric basic and advanced life support: 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

Note From the Writing Group: Throughout this article, the reader will notice combinations of superscripted letters and numbers (eg, “Family Presence During ResuscitationPeds-003”). These callouts are hyperlinked to evidence-based worksheets, which were used in the development of this article. An appendix of worksheets, applicable to this article, is located at the end of the text. The worksheets are available in PDF format and are open access.

Procedural Sedation and Analgesia in Children: Perspectives from Paediatric Emergency Physicians

Procedural sedation and analgesia in children is now widely practised in many emergency departments internationally. In this article, we address the general principles, indications, guidelines, medications, adverse events and future research in paediatric procedural sedation and analgesia in the Emergency Department.

Procedural sedation and analgesia is the use of sedative, analgesia and dissociative drugs to provide anxiolysis, analgesia, sedation and motor control during painful or unpleasant diagnostic and therapeutic procedures. It is a continuous spectrum from mild, moderate, deep sedation and then general anaesthesia. Dissociative sedation from ketamine is also commonly used.

Internationally, major clinical guidelines have been issued and revised since the 1980s. The guidelines should include the following components and documentation: pre-sedation assessment, intra-procedural monitoring and post-procedural monitoring and discharge criteria. The pre-sedation assessment involves assessing suitability of patient as candidate for sedation, any contraindications, fasting time, ensuring that the necessary equipment and drugs are available and the personnel providing the sedation are skilled in sedation and resuscitation.

The common medications for sedation in the emergency departments include ketamine, midazolam, fentanyl, morphine, oral chloral hydrate and nitrous oxide inhalation. Propofol and etomidate are used widely in some of the paediatric emergency departments internationally.

Procedural sedation has been documented to be safe and effective when performed by trained emergency physicians. The overall incidence of complications was 5.3% in a large prospective study, including airway and respiratory events (laryngospasm, apnoea, desaturations) and emesis. Aspirations are rare complications. Though the risks of adverse events are not high, emergency physicians need to have core competencies in sedation and resuscitation skills. The future of procedural sedation and analgesia will focus on enhancing training, safety and effectiveness.

Ketamine/midazolam versus etomidate/fentanyl: procedural sedation for pediatric orthopedic reductions

BACKGROUND

Orthopedic reductions are commonly performed procedures requiring sedation in the pediatric emergency department (PED). Ketamine is a widely used agent for pediatric procedural sedation, but its use may present difficulties in select populations, such as those with psychiatric diagnoses. In such a case, alternative agents that are safe and effective are needed. Etomidate is a commonly used induction agent for rapid-sequence intubation in the PED. Several retrospective and few prospective studies support etomidate's safety and efficacy in pediatric procedural sedation.

OBJECTIVE

The objective was to compare etomidate/fentanyl (E/F) with ketamine/midazolam (K/M) for procedural sedation during orthopedic reductions in the PED.

METHODS

Prospective, partially blinded, randomized controlled study comparing intravenously administered K/M with intravenously administered E/F. A convenience sample of patients, aged 5 to 18 years, presenting to an urban PED with fracture requiring reduction was enrolled. Outcome measures included guardian and staff completion of visual analog scale and Likert scales for observed pain and satisfaction, blinded OSBD-r (Observational Scale of Behavioral Distress-Revised) scoring of digital recordings of reductions, and sedation and recovery times. Descriptive tracking of adverse effects, adverse events, and interventions were recorded at the sedation.

RESULTS

Twenty-three patients were enrolled, 11 in the K/M group and 12 in the E/F group. The K/M group had significantly lower mean OSBD-r scores compared with the E/F group (0.08 vs 0.89, P = 0.001). Parents rated lower visual analog scale scores with K/M than with E/F (13.7 vs 50.5, P = 0.003) and favored K/M on a 5-point satisfaction scale (P = 0.004). The E/F group had significantly shorter total sedation times (49.6 vs 77.6 minutes, P = 0.003) and recovery times (24.7 vs 61.4 minutes, P = 0.000). There were no significant differences with respect to procedural amnesia and orthopedic practitioner satisfaction. Adverse effects noted in the K/M group included dysphoric emergence reaction and vomiting. Vomiting, injection-site pain, myoclonus, airway readjustment, and supplemental oxygen use were observed in the E/F group.

CONCLUSIONS

This is a small study that strongly suggests that, for pediatric orthopedic reductions, K/M is more effective at reducing observed distress than E/F, although both provide equal procedural amnesia. With its significantly shorter sedation and recovery times, E/F may be more applicable for procedural sedation for shorter, simpler procedures in the PED.

Hemodynamic responses to etomidate in pediatric patients with congenital cardiac shunt lesions

OBJECTIVE

The authors investigated the effects of intravenous etomidate on hemodynamics in children with congenital cardiac shunts.

DESIGN

Prospective observational study.

SETTING

Catheterization laboratory in tertiary referral cardiac center.

PARTICIPANTS

Thirty children with congenital cardiac shunt lesions.

INTERVENTIONS

Fifteen children having congenital right to left shunts (group A) and 15 children with left to right shunts (group B) were studied. Systemic mean arterial pressure (SMAP), mean pulmonary artery pressures (MPAP), right atrial pressures (RAP), and pulmonary artery wedge pressure (PAWP) were recorded. Systemic vascular resistance index (SVRI), pulmonary vascular resistance index (PVRI), and pulmonary-to-systemic blood flow ratio (Qp/Qs) were calculated on room air at baseline and following a single dose of 0.3 mg/kg of etomidate.

MEASUREMENTS AND MAIN RESULTS

Heart rate (HR), SMAP, RAP, systemic blood flow (Qs), Qp/Qs, and SVRI did not show any significant change; whereas systemic arterial saturation increased from 77.3% to 79.3%, which was statistically but not clinically significant in the authors' opinion following etomidate in group A. No significant differences in HR, SMAP, MPAP, PAWP, PVRI, SVRI, Qs, pulmonary blood flow (Qp), and Qp/Qs ratio were seen; whereas RAP, systemic, and pulmonary artery saturation decreased in group B after etomidate. Although statistically significant, the decreases were not clinically significant.

CONCLUSION

Etomidate at 0.3 mg/kg produces very minimal changes in hemodynamic parameters and shunt fraction in children with congenital shunt lesions.

Sedation after intubation using etomidate and a long-acting neuromuscular blocker

BACKGROUND

Etomidate is an imidazole hypnotic which is commonly used by emergency medicine physicians during rapid sequence intubation. Etomidate's duration of action is significantly shorter than that of commonly used long-acting paralytic medications (3-12 minutes vs 25-73 minutes). If additional sedative medications are not administered in the paralyzed patient before the conclusion of etomidate's duration of action, patients are at risk for experiencing paralysis without adequate sedation.

OBJECTIVE

To evaluate the frequency of the administration of additional sedation in pediatric emergency department patients undergoing endotracheal intubation with etomidate and a long-acting paralytic agent.

METHODS

This study was a retrospective review of pediatric patients undergoing endotracheal intubation in a tertiary pediatric emergency department between July 2001 and December 2005. All patients intubated with etomidate and rocuronium or vecuronium were eligible for inclusion; patients with seizures were excluded. Data elements included the following: demographic variables, presenting complaint, intubation indication, medications used, time from etomidate administration to the administration of an additional sedative, Glasgow Coma Scale (GCS) score, and patient disposition.

RESULTS

During the study period, 276 pediatric intubations were reviewed with 104 patients receiving etomidate and rocuronium or vecuronium. Twenty cases were excluded, 15 cases with documented seizures and 5 incomplete/missing charts. Eighty-four records were included in the final analysis. The mean age is 84 +/- 65 months; 62 (73.8%) patients were male; the mean GCS was 8.44 +/- 3.9, with a median GCS of 8 (interquartile range 6,11), and 41 (48.8%) of patients presented with blunt trauma. The mean time from etomidate to the administration of additional sedation was 46 +/- 49 minutes. Eleven (13.1%) patients received no additional sedative after etomidate administration, whereas only 20 (23.8%) patients were given a sedative within 15 minutes of the administration of etomidate. Fifty-three (63.1%) patients received an additional sedative more than 15 minutes after the administration of etomidate.

CONCLUSIONS

A significant proportion of pediatric patients receiving etomidate and rocuronium or vecuronium during endotracheal intubation are likely experiencing ongoing paralysis without adequate sedation. Emergency medicine physicians should be cognizant of this when using these medications for facilitating intubation.

Rapid sequence intubation in the neonate

Rapid sequence intubation (RSI) is premedication prior to intubation that includes atropine, a sedative, and a neuromuscular blockage. Rapid sequence intubation is infrequently performed in neonates despite evidence that it is safe and effective. Neonates that experience endotracheal intubation often display apnea and cardiac arrhythmias, decreased or obstructed nasal airflow, increased systolic blood pressure, and decreased heart rate and transcutaneous oxygen tension. Infants can also experience increased anterior fontanel pressure, which can place them at greater risk for intraventricular hemorrhage. Rapid sequence intubation has been shown to facilitate better intubation conditions including no movement from the infant and better visualization of the airway. Infants receiving RSI were successfully intubated twice as fast as infants who were not premedicated. Infants with premedication also had fewer changes in baseline heart rate. Neonatal RSI can be easily and safely performed in the neonate. Knowledge and skill allow for the best conditions when intubating the infant. Future research must focus on the best combination of medications for RSI in the neonate.

Newer agents for rapid sequence intubation: etomidate and rocuronium

The emergency airway management of children and adolescents with critical illnesses may necessitate rapid sequence intubation with a sedating and a neuromuscular blocking agent. Etomidate and rocuronium have become increasingly popular for the sedation and paralysis, respectively, of pediatric patients in rapid sequence intubation, and there are many advantages to the use of both agents. Both etomidate and rocuronium have a rapid onset of action, and both agents are relatively free of hemodynamic adverse effects. Etomidate does, however, suppress adrenal function, and consequently, its use in patients with septic shock is controversial. Rocuronium can produce optimal intubating conditions without the serious complications that can accompany succinylcholine. The available evidence supports the safety of etomidate and rocuronium in rapid sequence intubation but also suggests that more prospective studies are needed in pediatric patients.

No evidence for decreased incidence of aspiration after rapid sequence induction

PURPOSE

The purpose of this structured, evidence-based, clinical update was to determine if rapid sequence induction is a safe or effective technique to decrease the risk of aspiration or other complications of airway management.

SOURCE

In June 2006 a structured search of MEDLINE from 1966 to present using OVID software was undertaken with the assistance of a reference librarian. Medical subject headings and text words describing rapid sequence induction or intubation (RSI), crash induction or intubation, cricoid pressure and emergency airway intubation were employed. OVID's therapy (sensitivity) algorithm was used to maximize the detection of randomized trials while excluding non-randomized research. The bibliographies of eligible publications were hand-searched to identify trials not identified in the electronic search.

PRINCIPAL FINDINGS

A total of 184 clinical trials were identified of which 163 were randomized controlled trials (RCTs). Of these clinical trials, 126 evaluated different drug regimens with 114 being RCTs. Only 21 clinical trials evaluated non-pharmacologic aspects of the RSI with 18 RCTs identified. A parallel search found 52 trials evaluating cricoid pressure (outside of the context of an RSI technique) with 44 classified as RCTs. Definitive outcomes such as prevention of aspiration and mortality benefit could not be evaluated from the trials. Likewise, the impact on adverse outcomes of the different components of RSI could not be ascertained.

CONCLUSION

An absence of evidence from RCTs suggests that the decision to use RSI during management can neither be supported nor discouraged on the basis of quality evidence.

Complications of emergency tracheal intubation: hemodynamic alterations--part I

Emergency airway management outside the elective operating room presents considerable risks to the patient and significant challenges to the practitioner. Complications and adverse consequences are commonplace, yet they have not received their justified discussion or scrutiny in the literature. This review will discuss potentially life-threatening complications partitioned into 2 broad categories: hemodynamic and airway. Part 1 will focus on alterations in the heart rate and blood pressure, new onset cardiac dysrhythmias and cardiac arrest. Part 2 will explore airway related consequences such as hypoxemia, esophageal intubation, multiple intubation attempts, and aspiration.

Etomidate Versus Midazolam for Procedural Sedation in Pediatric Outpatients: A Randomized Controlled Trial

STUDY OBJECTIVE

Midazolam is widely used for procedural sedation and analgesia. Etomidate has been studied mostly in adults. Our objective is to compare the efficacy of etomidate and midazolam for achieving procedural sedation and analgesia in children.

METHODS

A randomized, double-blind, emergency department and orthopedic clinic-based trial was carried out among patients aged 2 to 18 years with displaced extremity fractures. Patients were administered 1 microg/kg of fentanyl and either 0.2 mg/kg of etomidate or 0.1 mg/kg of midazolam. Adequate sedation was defined, for the purpose of this study, as a score of 4 or more on the Ramsay Sedation Scale. The primary outcome was induction and recovery time. The rates of adverse events, success of fracture reduction, and parent and physician satisfaction were also compared.

RESULTS

From April to August 2004, 100 of 128 eligible patients were enrolled (age 8.7+/-3.7 years; 50% male patients). A higher proportion of patients attained adequate sedation among those who received etomidate: 46 of 50 (92%) versus 18 of 50 (36%) (delta 56%; 95% confidence interval [CI] 38% to 69%). Time taken for induction (hazard ratio 4.9; 95% CI 2.2 to 10.9) and time taken for recovery (hazard ratio 2.8; 95% CI 1.5 to 5.1) were lower among patients who received etomidate. The rates of adverse events were similar in both groups, except for myoclonus and pain at the injection site, which was more frequent in the etomidate group.

CONCLUSION

Induction and recovery times are shorter with etomidate compared with midazolam. At the dosages used for procedural sedation and analgesia among children with displaced extremity fracture, etomidate has higher efficacy in comparison with midazolam.

The association of preprocedural anxiety and the success of procedural sedation in children

PURPOSE

To investigate the association between a child's preprocedural state anxiety and the success of sedation.

METHODS

A consecutive sample of children aged 2 through 17 years requiring sedation for a procedure was enrolled. Pain, preprocedural anxiety (range, 0-9), and success of sedation (10=most successful) were measured.

RESULTS

Fifty-nine patients were enrolled. The median age was 7 years. The median anxiety score was 1.0 (interquartile ratio, 0-3). Pain and anxiety were weakly correlated (r=.21, P>.10). The mean sedation score was 7.8 (+/-2.2). Preprocedural anxiety and successful sedation were inversely correlated (r=-0.31, P=.002). Sedation was successful in 81% of children with anxiety scores below the median and 52% with anxiety scores above the median (P=.02). Children with low anxiety were 3.8 times more likely to be successfully sedated (95% confidence interval, 1.19-12.14).

CONCLUSION

Our data suggest that preprocedural state anxiety is associated with the success of sedation in children.

Use of etomidate as an induction agent for rapid sequence intubation in a pediatric emergency department

OBJECTIVES

Although etomidate is widely used for rapid sequence intubation (RSI), there is no consensus on the optimal induction agent and no prospective pediatric emergency department (ED) study exists. The objective of this study was to assess the effectiveness and safety of etomidate as an induction agent for RSI in the pediatric ED.

METHODS

Data on RSI conditions and complications were collected prospectively on patients undergoing RSI in a tertiary pediatric ED from January 2003 to December 2003. ED hemodynamic data and inpatient data were collected retrospectively via chart review.

RESULTS

Seventy-seven of 101 patients requiring intubation underwent RSI with etomidate. The mean (+/- SD) age was 8.2 (+/- 6.2) years. All 77 patients were successfully intubated. Intubation condition data were available for 69 of 77 patients (89.6%). Conditions were good in 68 of 69 (99%; 95% confidence interval = 92.2% to 99.9%). The mean (+/- SD) maximal percent decrease in systolic blood pressure was 10% (+/- 13.6%). A greater than 20% maximal percent decrease in systolic blood pressure occurred in 12 of 69 patients (17.4%; 95% confidence interval = 9.3% to 28.4%). There was no relationship between seizures after etomidate administration and prior seizure history (p = 0.25). Corticosteroids were given to 29 of 77 patients post-RSI for varying diagnoses. All eight patients given corticosteroids for shock were in shock at the time of intubation.

CONCLUSIONS

In the pediatric ED setting, etomidate as an induction agent provided successful RSI conditions and resulted in varied hemodynamic changes that were especially favorable in those patients presenting in decompensated shock. Hypotension and seizures were uncommon and occurred in patients with confounding diagnoses. Until the significance of a single dose of etomidate on adrenal dysfunction is further clarified, caution should be used in those patients at risk for adrenal insufficiency.

Intubating conditions and hemodynamic effects of etomidate for rapid sequence intubation in the emergency department: an observational cohort study

OBJECTIVES

To describe and analyze the intubating conditions and hemodynamic effects of etomidate in patients undergoing rapid sequence intubation (RSI) in the emergency department.

METHODS

The authors conducted a prospective observational study of all patients who received etomidate for induction of RSI over a 42-month period in a large tertiary care teaching hospital. Intubating conditions were determined by the emergency physician for both sedation and paralysis and for technical difficulty using a five-point Likert scale. Hemodynamic effects were evaluated before, after, and every five minutes for 15 minutes following administration of etomidate.

RESULTS

Etomidate was used for induction of RSI in 522 patients, all of whom were included in the final efficacy analysis, while 491 were included in the analysis of hemodynamics. Lidocaine and fentanyl were used as pretreatment in 65.1% and 26.1% of patients, respectively, while succinylcholine was the paralytic in 94.3% of intubations. Sedation and paralysis were rated as excellent or good in 88.1% and 8.8% of patients, respectively, while technical difficulty was very easy or easy in 60.7% and 19.0% of patients, respectively. Mean (+/- SD) baseline systolic blood pressure (sBP), diastolic blood pressure (dBP), and heart rate were found to be 132.7 (+/- 35.4) mm Hg, 69.5 (+/- 21.2) mm Hg, and 96.1 (+/- 26.2) bpm, respectively. Overall, there was a clinically insignificant elevation in sBP (p < 0.0001), dBP (p = 0.0002), and heart rate (p < 0.0001) immediately postintubation. Elevations in sBP persisted at five minutes (p = 0.0230) and ten minutes (p = 0.0254) postintubation. Diastolic blood pressure and heart rate returned to baseline at five minutes after intubation and remained stable throughout the 15-minute postintubation assessment period. In the subgroup of 80 patients with a preintubation sBP < 100 mm Hg, there was a 12.1-mm Hg elevation in sBP (p < 0.0001) and a 7.3-mm Hg elevation in dBP (p = 0.0001) immediately postintubation. This elevation persisted throughout the 15-minute postintubation assessment period.

CONCLUSIONS

Etomidate appears to provide appropriate intubating conditions in a heterogeneous group of patients undergoing RSI in the emergency department. Hemodynamic stability appears to be present following administration of this agent, even in patients with low pre-RSI blood pressure. This attribute must be weighed against potential adverse effects of this agent, including adrenal suppression.

The effect of etomidate on intracranial pressure and systemic blood pressure in pediatric patients with severe traumatic brain injury

OBJECTIVE

To evaluate the effects of single-dose etomidate in pediatric patients with intracranial hypertension after severe traumatic brain injury.

METHODS

Patients admitted to the pediatric intensive care unit with severe traumatic brain injury were enrolled with the informed consent of their guardians. The experimental intervention was a single dose of etomidate 0.3 mg/kg intravenously. This dosage was administered only when enrolled patients had acute elevations of intracranial pressure (ICP) to over 20 mm Hg for over 5 minutes. ICP and mean arterial pressure (MAP) were monitored continuously. ICP and MAP values for 6 consecutive 5-minute intervals after etomidate administration were averaged for all patients and compared with baseline.

RESULTS

Eight patients were enrolled. Mean ICP after etomidate administration was significantly lower than baseline ICP for each 5-minute interval (P < 0.05). The mean MAP for all patients increased from baseline during the first 5-minute interval, but this change was not statistically significant. No patient's MAP decreased below baseline at any time point.

CONCLUSIONS

In pediatric patients with severe traumatic brain injury, single-dose etomidate administration resulted in statistically significant reductions in ICP and improvement in cerebral perfusion pressure without significantly altering MAP.

Hemodynamic Responses to Etomidate on Induction of Anesthesia in Pediatric Patients

Etomidate is often used for inducing anesthesia in patients who have limited hemodynamic reserve. Using invasive hemodynamic monitoring, we studied the acute effects of a bolus of etomidate during induction of anesthesia in children. Twelve children undergoing cardiac catheterization were studied (mean age, 9.2 +/- 4.8 yr; mean weight, 33.4 +/- 15.4 kg); catheterization procedures included device closure of secundum atrial septal defects (n = 7) and radiofrequency catheter ablation procedures for supraventricular tachycardia (n = 5). Using IV sedation, a balloon-tipped pulmonary artery catheter was placed to measure intracardiac and pulmonary artery pressures and oxygen saturations. Baseline measurements were recorded and then repeated after a bolus of IV etomidate (0.3 mg/kg). For the entire group, no significant changes in right atrial, aortic, or pulmonary artery pressure, oxygen saturations, calculated Qp:Qs ratio or systemic or pulmonary vascular resistance were detected after the bolus dose of etomidate. The lack of clinically significant hemodynamic changes after etomidate administration supports the clinical impression that etomidate is safe in children. Further research is needed to determine the hemodynamic profile of etomidate in neonates and in pediatric patients with severe ventricular dysfunction and pulmonary hypertension.

Etomidate and midazolam for procedural sedation: prospective, randomized trial

OBJECTIVE

To evaluate whether there is a difference in the time of sedation and time to patient disposition in patients undergoing procedural sedation with etomidate and midazolam.

METHODS

Prospective, randomized, double-blind trial comparing etomidate (0.10 mg/kg) and midazolam (0.035 mg/kg) for patients requiring procedural sedation for reduction of joint dislocations or long bone fractures.

RESULTS

Forty-five patients were enrolled (24 randomized to etomidate, 21 to midazolam). Groups were similar in demographics and analgesic dosing. Mean time of sedation for etomidate was 15 minutes (SD, 10.97) and for midazolam was 32 minutes (SD, 16.13) (P<.001). Mean time to disposition for etomidate was 121 minutes (SD, 73.28) and for midazolam was 111 minutes (SD, 96.36) (P=.700). The mean quality of sedation for etomidate was 7.91 (SD, 1.53) and for midazolam was 7.48 (SD, 2.89) (P=.570).

CONCLUSIONS

The use of etomidate compared with midazolam for procedural sedation provides a significant reduction in recovery time, without a reduction in time to patient disposition, while providing equal sedation quality.

Controversies in rapid sequence intubation in children

PURPOSE OF REVIEW

Rapid sequence intubation is the method of choice for intubation of the emergency department patient. The purpose of the present review is to address several controversies pertaining to emergency department rapid sequence intubation of children.

RECENT FINDINGS

The topics covered in this review include the determination of the appropriate clinician to perform emergency department intubation, the use of atropine and lidocaine as premedications, the choice of sedative agents depending upon the clinical scenario, and the choice of neuromuscular blockade agent. Concerning these topics: The literature supports that emergency department physicians, with appropriate training, successfully perform intubation in most patients. Limited data exist to determine the appropriate use of atropine and lidocaine for rapid sequence intubation. Etomidate has clearly become a preferred sedative for rapid sequence intubation with a low risk of cardiovascular side effects. Thiopental and propofol may more readily provide adequate sedation as compared with etomidate but both have the potential to reduce blood pressure. Succinylcholine arguably remains the preferred neuromuscular blockade agent for rapid sequence intubation in most children. The side effects of succinylcholine occur in relatively predictable circumstances. Rocuronium is a commonly used nondepolarizing paralytic agent but its prolonged duration of action must be weighed against the risk of side effects associated with succinylcholine.

SUMMARY

Though more research is needed, the available data allow for the development of protocols that will result in a rational, scenario-based approach to rapid sequence intubation in children.

Should etomidate be the induction agent of choice for rapid sequence intubation in the emergency department?

The ideal induction agent for emergency airway management should be rapidly acting, permit optimum intubating conditions, and be devoid of significant side effects. This review was performed to ascertain whether etomidate should be the induction agent of choice for rapid sequence intubation (RSI) in the emergency department, specifically examining its pharmacology, haemodynamic profile, and adrenocortical effects. A search of Medline (1966-2002), Embase (1980-2002), the Cochrane controlled trials register, and CINAHL was performed. In addition, the major emergency medicine and anaesthesia journals were hand searched for relevant material. Altogether 144 papers were identified of which 16 were relevant. Most studies were observational studies or retrospective reviews with only one double blind randomised controlled trial and one un-blinded randomised controlled trial. Appraisal of the available evidence suggests that etomidate is an effective induction agent for emergency department RSI; it has a rapid onset of anaesthesia and results in haemodynamic stability, even in hypovolaemic patients or those with limited cardiac reserve. Important questions regarding the medium to long term effects on adrenocortical function (even after a single dose) remain unanswered.

Etomidate versus pentobarbital for sedation of children for head and neck CT imaging

OBJECTIVES

We compare etomidate to pentobarbital for sedation of children for head and neck computed tomography imaging.

METHODS

We performed a prospective, randomized, double-blinded trial of patients aged 6 months to 6 years enrolled from the emergency department or radiology department at a large urban children's hospital. The primary outcome measure was sedation success rate.

RESULTS

A total of 61 patients were enrolled in the study (27 etomidate group, 34 pentobarbital group) at 2 different dosing regimens for etomidate. The final analysis group included 17 etomidate patients and 33 pentobarbital patients. The success rate for the etomidate group was 57% at total doses of up to 0.3 mg/kg (n = 7) and 76% at total doses of up to 0.4 mg/kg (n = 17), in contrast to a success rate of 97% for pentobarbital at a total dose of up to 5 mg/kg (n = 33). The success rate for pentobarbital was significantly greater than the final etomidate group (P = 0.04; difference in proportions 20.5%, 95% CI 1.9% to 44.4%). Patients receiving etomidate had significantly shorter induction times (P = 0.02; difference of means 2.1 minutes, 95% CI 0.35 to 3.86), sedation times (P < 0.001; difference of means 31.3 minutes, 95% CI 24.0 to 38.5), and total examination times (P < 0.001; difference of means 53.1 minutes, 95% CI 40.8 to 65.3). Significantly more parents in the etomidate group perceived their child to be back to baseline by discharge from the hospital (P < 0.001; difference of proportions 60.7, 95% CI 29.1 to 92.4) and expressed fewer concerns about their child's behavior after discharge (P = 0.024; difference of proportions 28.6, 95% CI 6.5 to 50.7).

CONCLUSIONS

At the dosing used in this study, pentobarbital is superior to etomidate when comparing success rates for sedation. However, among the successful sedations, the duration of sedation was shorter in the etomidate group than in the pentobarbital group. Pentobarbital is associated with more frequent side effects and parental concerns compared to etomidate.

Etomidate for procedural sedation in the emergency department

OBJECTIVE

To review the current efficacy and safety evidence for the use of etomidate for procedural sedation in the emergency department (ED).

DATA SOURCES

MEDLINE (1966-December 2003), EMBASE (1980-December 2003), PubMED (1966-December 2003), and Cochrane Database of Systemic Reviews (up to December 2003) were searched for full-text reports published in English on the use of etomidate in humans. Search terms included etomidate, procedural sedation, conscious sedation, relocation, dislocation, abscess incision, abscess drainage, and cardioversion.

STUDY SELECTION AND DATA EXTRACTION

Prospective and retrospective studies evaluating efficacy or safety endpoints using etomidate for procedural sedation in the ED were included. All studies were evaluated independently by both authors. For clinical outcomes (efficacy, safety), the definitions specified by each study were used.

DATA SYNTHESIS

Three observational studies and 5 prospective, randomized controlled trials were included in this review. Onset of action and time to recovery following etomidate were rapid and found to be comparable to that of propofol and thiopental but significantly faster than that of midazolam. The dose of etomidate for procedural sedation ranged from 0.15 to 0.22 mg/kg. No significant hemodynamic effects were observed; however, respiratory depression resulting in oxygen desaturation to <90% or apnea appears to occur in approximately 10% of patients undergoing procedural sedation with etomidate with or without analgesia. The most prominent adverse effect reported with etomidate was myoclonus, occurring in 20-45% of patients.

CONCLUSIONS

Etomidate is an appropriate and valuable agent for performing procedural sedation in the ED. The rapid onset and recovery time and relative lack of significant hemodynamic and respiratory effects may facilitate optimal and safe conditions for procedural sedation in the ED.

Newer pharmacologic agents for procedural sedation of children in the emergency department-etomidate and propofol

Procedural sedation for pediatric patients having painful or anxiety-producing procedures is a necessary but often a daunting task for emergency medicine providers. This article focuses on the two agents that have most recently been described for use in this population-etomidate and propofol. Etomidate is a nonbarbiturate sedative hypnotic agent with no analgesic properties. Its rapid onset of action, short duration of action, and minimal hemodynamic effects make it an attractive agent for use in procedural sedation. Similar to previous adult studies, recent studies have shown that etomidate is both safe and effective in this pediatric population. Propofol is also a sedative hypnotic agent with rapid onset and short duration of action. Typically, it is administered as a bolus injection followed by an infusion. It has long been used for surgical procedures as well as in the intensive care unit setting, but little literature has supported its use in the pediatric emergency department. Recent studies appear to support propofol's use in this setting; however, a significant rate of side effects, including hypoxia, apnea, and decreased blood pressure, may limit its use.