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

The Effect of Ketamine Versus Etomidate for Rapid Sequence Intubation on Maximum Sequential Organ Failure Assessment Score: A Randomized Clinical Trial

BACKGROUND

The use of induction agents for rapid sequence intubation (RSI) has been associated with hypotension in critically ill patients. Choice of induction agent may be important and the most commonly used agents are etomidate and ketamine.

OBJECTIVE

This study aimed to compare the effects of a single dose of ketamine vs. etomidate for RSI on maximum Sequential Organ Failure Assessment (SOFA) score and incidence of hypotension.

METHODS

This single-center, randomized, parallel-group trial compared the use of ketamine and etomidate for RSI in critically ill adult patients in the emergency department. The study was performed under Exception from Informed Consent. The primary outcome was the maximum SOFA score within 3 days of hospitalization.

RESULTS

A total of 143 patients were enrolled in the trial, 70 in the ketamine group and 73 in the etomidate group. Maximum median SOFA score for the ketamine group was 6.5 (interquartile range [IQR] 5-9) vs. 7 (IQR 5-9) for etomidate with no significant difference (-0.2; 95% CI -1.4 to 1.1; p = 0.79). The incidence of post-intubation hypotension was 28% in the ketamine group vs. 26% in the etomidate group (difference 2%; 95% CI -13% to 17%). There were no significant differences in intensive care unit outcomes. Thirty-day mortality rate for the ketamine group was 11% (8 deaths) and for the etomidate group was 21% (15 deaths), which was not statistically different.

CONCLUSIONS

There were no significant differences in maximum SOFA score or post-intubation hypotension between critically ill adults receiving ketamine vs. etomidate for RSI.

Pharmacotherapy optimization for rapid sequence intubation in the emergency department

PURPOSE

Rapid-sequence intubation (RSI) is the process of administering a sedative and neuromuscular blocking agent (NMBA) in rapid succession to facilitate endotracheal intubation. It is the most common and preferred method for intubation of patients presenting to the emergency department (ED). The selection and use of medications to facilitate RSI is critical for success. The purpose of this review is to describe pharmacotherapies used during the RSI process, discuss current clinical controversies in RSI medication selection, and review pharmacotherapy considerations for alternative intubation methods.

SUMMARY

There are several steps to the intubation process requiring medication considerations, including pretreatment, induction, paralysis, and post-intubation sedation and analgesia. Pretreatment medications include atropine, lidocaine, and fentanyl; but use of these agents in clinical practice has fallen out of favor as there is limited evidence for their use outside of select clinical scenarios. There are several options for induction agents, though etomidate and ketamine are the most used due to their more favorable hemodynamic profiles. Currently there is retrospective evidence that etomidate may produce less hypotension than ketamine in patients presenting with shock or sepsis. Succinylcholine and rocuronium are the preferred neuromuscular blocking agents, and the literature suggests minimal differences between succinylcholine and high dose rocuronium in first-pass success rates. Selection between the two is based on patient specific factors, half-life and adverse effect profiles. Finally, medication-assisted preoxygenation and awake intubation are less common methods for intubation in the ED but require different considerations for medication use.

AREAS FOR FUTURE RESEARCH

The optimal selection, dosing, and administration of RSI medications is complicated, and further research is needed in several areas. Additional prospective studies are needed to determine optimal induction agent selection and dosing in patients presenting with shock or sepsis. Controversy exists over optimal medication administration order (paralytic first vs induction first) and medication dosing in obese patients, but there is insufficient evidence to significantly alter current practices regarding medication dosing and administration. Further research examining awareness with paralysis during RSI is needed before definitive and widespread practice changes to medication use during RSI can be made.

A Comparative Study of the Effect of Anesthesia Induction with the Use of Four Drug Combinations Including "Propofol," "Etomidate-Propofol," "Thiopental," and "Midazolam-Thiopental" on Hemodynamic Changes during the Insertion of Laryngeal Mask in Eye Surgery

Background:

This study aimed to compare the efficacies of four anesthetic induction drugs (thiopental, propofol, midazolam-thiopental, and etomidate-propofol) on cardiovascular response during laryngeal mask airway (LMA) placement in eye surgery.

Materials and Methods:

The present clinical trial study included 128 patients who were candidates for ophthalmic surgery in four groups. Patients in the first group were given a combination of midazolam (0.04 mg/kg) with thiopental (2.5 mg/kg) (Group T + M). We administered propofol alone (2.5 mg/kg) to patients in the second group (Group P). The third group received a combination of etomidate (0.1 mg/kg) with propofol (1 mg/kg) (ET + P group) and patients in the fourth group received thiopental drug (5 mg/kg) alone (Group T). Then, the stability of patients' hemodynamic parameters before anesthesia was evaluated and compared immediately after anesthesia, 1, 3, and 5 min after LMA placement.

Results:

There was no significant difference between the four groups in changes in oxygen saturation level (P > 0.05). Furthermore, the difference between decreased systolic blood pressure and diastolic blood pressure over time was not significant in 5 min in both Groups T + M and T (P > 0.05). In addition, the stability of these two groups was higher than the other two groups (P < 0.05) and the most unstable group was Group P. The changes pulse ratein the P group were significant (P < 0.05).

Conclusion:

According to the results of the current study, thiopental and Midazolam can be used as an effective induction compound to facilitate LMA insertion with higher hemodynamic stability compared to propofol alone, propofol and etomidate, and thiopental alone.

Rapid sequence induction/intubation controversies

Backgrounds:

Since its first definition and publication on 1970, Rapid Sequence Induction / Intubation (RSI) technique has been accepted globally as the “standard” for doing rapid intubation after induction of anesthesia for patients with high risk of aspiration, especially in emergency situation. However, this technique is not so much a “standard” as there are numerous variations on its practice based on national surveys. Anesthesia providers have their own opinions on the practice of RSI components which need to be discussed to assess their advantages and disadvantages, while there has been no review article which discussed these controversies in the last ten years.

Objectives:

To review the technique differences within RSI protocols.

Methods:

Online databases were searched, including MEDLINE and COCHRANE for each step in the original RSI protocol using keywords such as: “rapid sequence induction” or “rapid sequence intubation” or “RSI” and “controversies” or “head position” or “cricoid pressure” or “neuromuscular blocking agent” or “NMBA” or positive pressure ventilation” or “PPV”; and so on. Articles were then sorted out based on relevancy.

Results and conclusion:

Supported by new evidence, RSI practices may differ in: the positioning of patient, choices of induction agent, application of cricoid pressure, choices of neuromuscular blocking agent, and the use of positive pressure ventilation. A more updated and standardized guideline should be established by referring and evaluating to these controversies.

Association between Etomidate Use for Rapid Sequence Intubation and Adrenal Insufficiency in Sepsis

Background The risk of adrenal insufficiency (AI) in using single-dose etomidate for intubation among patients with sepsis remains controversial. Our aim was to assess the prevalence of AI and characterize the risk factors in patients who received etomidate for rapid sequence intubation (RSI). Methods This is a retrospective study of prospectively-acquired data evaluating surgical intensive care unit (SICU) patients who developed respiratory failure undergoing RSI. Results Of the 44 adult SICU patients who developed respiratory failure, 34 patients received etomidate. The average age for the total cohort, for the patients that received etomidate and for those who did not, was 70.91 ± 14.92, 72.82 ± 13.61 years and 64.40 ± 15.93, respectively. Twenty-four patients of the total cohort (54.55%) developed AI; 26 had septic shock (59.09%), and 16 patients had AI and septic shock (36.36%). There was no statistical significance between the incidence of AI in patients who received etomidate (47%) and those who did not (80%). However, in the subset of patients who received etomidate for RSI, there was a non-significant trend toward increased incidence of AI in those who were septic compared to those who were not (p = 0.06). Conclusion A single dose of etomidate used for RSI in SICU patients is not associated with the development of AI or mortality. However, a trend was shown, although not statistically significant, towards the development of AI in septic patients. High-quality and adequately powered randomized control trials (RCTs) are warranted.

Ketamine Versus Etomidate and Peri-intubation Hypotension: A National Emergency Airway Registry Study

BACKGROUND

The hemodynamic impact of induction agents is a critically important consideration in emergency intubations. We assessed the relationship between peri-intubation hypotension and the use of ketamine versus etomidate as an induction agent for emergency department (ED) intubation.

METHODS

We analyzed ED intubation data for patients aged >14 years from the National Emergency Airway Registry performed in 25 EDs during 2016 through 2018. We excluded patients with preintubation hypotension (systolic blood pressure <100 mm Hg) or cardiac arrest prior to intubation. The primary outcome was peri-intubation hypotension. Secondary outcomes included interventions for hypotension (e.g., intravenous fluids or vasopressors). We report adjusted odds ratios (aOR) from multivariable logistic regression models controlling for patient demographics, difficult airway characteristics, and intubation modality.

RESULTS

There were 738 encounters with ketamine and 6,068 with etomidate. Patients receiving ketamine were more likely to have difficult airway characteristics (effect size difference = 8.8%, 95% confidence interval [CI] = 5.3% to 12.4%) and to undergo intubation with video laryngoscopy (8.1%, 95% CI = 4.4% to 12.0%). Peri-intubation hypotension incidence was 18.3% among patients receiving ketamine and 12.4% among patients receiving etomidate (effect size difference = 5.9%, 95% CI = 2.9% to 8.8%). Patients receiving ketamine were more likely to receive treatment for peri-intubation hypotension (effect size difference = 6.5%, 95% CI = 3.9% to 9.3%). In logistic regression analyses, patients receiving ketamine remained at higher risk for peri-intubation hypotension (aOR = 1.4, 95% CI = 1.2 to 1.7) and treatment for hypotension (aOR = 1.8, 95% CI = 1.4 to 2.0). There was no difference in the aOR of hypotension between patients receiving ketamine at doses ≤1.0 mg/kg versus >1.0 mg/kg or patients receiving etomidate at doses ≤0.3 mg/kg versus >0.3 mg/kg.

CONCLUSIONS

Pending additional data, our results suggest that clinicians should not necessarily prioritize ketamine over etomidate based on concern for hemodynamic compromise among ED patients undergoing intubation.

The effect of ketamine on depth of hypnosis indices during total intravenous anesthesia-a comparative study using a novel electroencephalography case replay system

Ketamine may affect the reliability of electroencephalographic (EEG) depth-of-hypnosis indices as it affects power in high-frequency EEG components. The purpose of this study was to compare the effects of ketamine on three commonly-used depth-of-hypnosis indices by extending our EEG simulator to allow replay of previously-recorded EEG. Secondary analysis of previously-collected data from a randomized controlled trial of intravenous anesthesia with ketamine: Group 0.5 [ketamine, 0.5 mg kg^-1 bolus followed by a 10 mcg kg^-1 min^-1 infusion], Group 0.25 [ketamine, 0.25 mg kg^-1 bolus, 5 mcg kg^-1 min^-1 infusion], and Control [no ketamine]. EEG data were replayed to three monitors: NeuroSENSE (WAV), Bispectral Index (BIS), and Entropy (SE). Differences in depth-of-hypnosis indices during the initial 15 min after induction of anesthesia were compared between monitors, and between groups. Monitor agreement was evaluated using Bland-Altman analysis. Available data included 45.6 h of EEG recordings from 27 cases. Ketamine was associated with higher depth-of-hypnosis index values measured at 10 min (BIS, χ² = 8.01, p = 0.018; SE, χ² = 11.44, p = 0.003; WAV, χ² = 9.19, p = 0.010), and a higher proportion of index values > 60 for both ketamine groups compared to the control group. Significant differences between monitors were not observed, except between BIS and SE in the control group. Ketamine did not change agreement between monitors. The ketamine-induced increase in depth-of-hypnosis indices was observed consistently across the three EEG monitoring algorithms evaluated. The observed increase was likely caused by a power increase in the beta and gamma bands. However, there were no lasting differences in depth-of-hypnosis reported between the three compared indices.

Etomidate Sedation for Advanced Endoscopic Procedures

BACKGROUND AND STUDY AIM

Although propofol is widely used for sedation for endoscopic procedures, concerns remain regarding cardiopulmonary adverse events. Etomidate has little effect on the cardiovascular and respiratory systems, but patient satisfaction analysis is lacking. We compared the efficacy and safety of balanced propofol and etomidate sedation during advanced endoscopic procedures.

METHODS

As a randomized noninferiority trial, balanced endoscopic sedation was achieved using midazolam and fentanyl, and patients were randomly assigned to receive propofol (BPS) or etomidate (BES) as add-on drug. The main outcomes were sedation efficacy measured on a 10-point visual analog scale (VAS) and safety.

RESULTS

In total, 186 patients (94 in the BPS group and 92 in the BES group) were evaluated. BES did not show noninferiority in terms of overall patient satisfaction, with a difference in VAS score of -0.35 (97.5 % confidence interval -1.03 to ∞, p = 0.03). Among endoscopists and nurses, BES showed noninferiority to BPS, with differences in VAS scores of 0.06 and 0.08, respectively. Incidence of cardiopulmonary adverse events was lower in the BES group (27.7 versus 14.1 %, p = 0.023). Hypoxia occurred in 5.3 and 1.1 % of patients in the BPS and BES group (p = 0.211). Myoclonus occurred in 12.1 % (11/92) in the BES group. BES had lower risk of overall cardiopulmonary adverse events (odds ratio 0.401, p = 0.018).

CONCLUSIONS

BES was not noninferior to BPS in terms of patient satisfaction. However, BES showed better safety outcomes in terms of cardiopulmonary adverse events.

Difficult tracheal intubation in critically ill

Background

Endotracheal intubation in critically ill is a high-risk procedure requiring significant expertise in airway handling as well as understanding of pathophysiology of the disease process.

Main body

Critically ill patients are prone for hypotension and hypoxemia in the immediate post-intubation phase due to blunting of compensatory sympathetic response. Preoxygenation without NIV is frequently suboptimal, as alveolar flooding cause loss of alveolar capillary interface in many of these patients. All these factors, along with relative fluid deficit, neuromuscular fatigue and coexistent organ dysfunction lead to physiologically difficult airway. Airway in ICU can be classified as anatomically difficult, physiologically difficult and anatomically as well as physiologically difficult. Though rapid sequence intubation is the recommended method for securing airway in these patients, other methods like delayed sequence intubation awake intubation and double setup approach can be used in specific subgroups. Further research is needed in this field to set guidelines and fine tune airway management for patients with specific organ failure or dysfunction.

Conclusion

Airway in ICU should be managed according to the physiological as well as the anatomical abnormalities.

The pituitary adenylate cyclase-activating polypeptide (PACAP) protects adrenal function in septic rats administered etomidate

BACKGROUND

Both hyperinflammation during sepsis and etomidate can suppress adrenal function. In this study, we explored whether treatment with pituitary adenylate cyclase-activating polypeptide (PACAP) relieves adrenal suppression in cecal ligation and puncture (CLP)-induced septic rats.

MATERIALS AND METHODS

Female Sprague-Dawley rats were randomly divided into five groups (n=7 per group), including the sham group, sepsis group (CLP group), sepsis and etomidate group (CLP+ETO group), PACAP group, and etomidate alone group (ETO group). Rats were sacrificed on the third day of sepsis, and blood and adrenal gland samples were obtained for further testing.

RESULTS

The PACAP reduced the apoptosis rate of adrenal cells and peripheral lymphocytes, improving adrenal function, inhibiting the secretion of interferon gamma (IFN-γ) from peripheral lymphocytes, and slightly relieving the suppression of the adrenal function induced by the injection of etomidate in sepsis.

CONCLUSION

In septic conditions, the PACAP protects the adrenal gland by regulating peripheral inflammation, which slightly relieves the toxic effects of etomidate on adrenal function.

Etomidate for rapid sequence intubation in the emergency department: Is adrenal suppression a concern?

Etomidate has become one of the most commonly used induction agents in the United States during emergency department (ED) endotracheal intubation. While etomidate may be popular, concerns have been raised about possible adrenal suppression and subsequent adverse effects. In this paper we critically evaluate the recent literature and perspectives regarding the effect of etomidate on the adrenocortical system.

Suicide with Vecuronium and Etomidate: A Case Report and Review of the Literature

A case of suicidal death due to intravenous self-administration of vecuronium and etomidate by a registered nurse is being reported. Toxicologic blood analysis showed a vecuronium concentration of 0.023 mg/L, an etomidate concentration of 0.041 μg/mL, and an ethanol concentration of 113 mg/dL. The autopsy, toxicologic analysis, and crime scene investigation findings indicated that this was suicidal death caused by respiratory failure secondary to vecuronium administration exacerbated by sedation secondary to etomidate and ethanol use. Review of the medical literature and popular press media has identified several instances in which vecuronium has been used in homicidal deaths, but it has identified few cases in which vecuronium or etomidate, alone or in conjunction with another drug, have been used to commit suicide.

Prevention of etomidate-induced myoclonus: which is superior: Fentanyl, midazolam, or a combination? A Retrospective comparative study

Background

In this retrospective comparative study, we aimed to compare the effectiveness of fentanyl, midazolam, and a combination of fentanyl and midazolam to prevent etomidate-induced myoclonus.

Material/Methods

This study was performed based on anesthesia records. Depending on the drugs that would be given before the induction of anesthesia with etomidate, the patients were separated into 4 groups: no pretreatment (Group NP), fentanyl 1 μg·kg⁻¹ (Group F), midazolam 0.03 mg·kg⁻¹ (Group M), and midazolam 0.015 mg·kg⁻¹ + fentanyl 0.5 μg·kg⁻¹ (Group FM). Patients who received the same anesthetic procedure were selected: 2 minutes after intravenous injections of the pretreatment drugs, anesthesia is induced with 0.3 mg·kg⁻¹ etomidate injected intravenously over a period of 20–30 seconds. Myoclonic movements are evaluated, which were observed and graded according to clinical severity during the 2 minutes after etomidate injection. The severity of pain due to etomidate injection, mean arterial pressure, heart rate, and adverse effects were also evaluated.

Results

Study results showed that myoclonus incidence was 85%, 40%, 70%, and 25% in Group NP, Group F, Group M, and Group FM, respectively, and were significantly lower in Group F and Group FM.

Conclusions

We conclude that pretreatment with fentanyl or combination of fentanyl and midazolam was effective in preventing etomidate-induced myoclonus.

Critical airway skills and procedures

Airway management is a critical procedure and essential skill necessary for all physicians working in the emergency department. Optimal resuscitative treatment of medical and trauma patients often revolves around timely and effective airway interventions that can be challenging in the acute setting, especially in critical patients. Time-honored airway techniques and procedures combined with recent advances in rapid sequence intubation, video laryngoscopy, and further advanced airway techniques now offer emergency clinicians a wide range of exciting new options for improving this crucial component of acute care and management.

Renal endocrine manifestations during polytrauma: A cause of concern for the anesthesiologist

Nowadays, an increasing number of patients get admitted with polytrauma, mainly due to road traffic accidents. These polytrauma victims may exhibit associated renal injuries, in addition to bone injuries and injuries to other visceral organs. Nevertheless, even in cases of polytrauma, renal tissue is hyperfunctional as part of the normal protective responses of the body to external insults. Both polytrauma and renal injuries exhibit widespread renal, endocrine, and metabolic responses. The situation is very challenging for the attending anesthesiologist, as he is expected to contribute immensely, not only in the resuscitation of such patients, but if required, to allow the operative procedures in case of life-threatening injuries. During administration of anesthesia, care has to be taken, not only to maintain hemodynamic stability, but equal attention has to be paid to various renal protection strategies. At the same time, various renoendocrine manifestations have to be taken into account, so that a judicious use of anesthesia drugs can be made, to minimize the renal insults.

Impact of the United States propofol ban on emergency providers' procedural sedation agent choice and patient length of stay

BACKGROUND

In the recent past, propofol was temporarily removed from the emergency department (ED) for use in procedural sedation. We sought to determine which agents replaced it in clinical practice and the impact this change had on turnaround times (TAT) for sedated patients.

METHODS

This study is a retrospective chart review at a level one trauma center. Patients receiving sedative agents (propofol, ketamine, midazolam, and etomidate) were identified by pharmacy codes, and their charts were then reviewed for demographics and TAT. Propofol was unavailable in the emergency department (ED) between May 2010 and February 2011. The study period extended from May 2009 until May 2011. Patients receiving sedation by non-emergency medicine physicians and those receiving sedation related to intubation were excluded.

RESULTS

In total 2466 charts were reviewed and 209 met inclusion criteria. When propofol was available, the most commonly used sedative agent was etomidate (40%), followed by propofol (28%), ketamine (20%), and midazolam (6%). When propofol was unavailable, etomidate remained the most commonly used agent (43%), followed by ketamine (41%), and midazolam (11%). When propofol was available, the median TAT for sedated patients was 163 minutes compared to 178 minutes when propofol was unavailable (P=0.83). When propofol was the primary sedative agent used, the median TAT was 166 minutes as compared with a median TAT of 172 minutes for all other sedative agents combined (P=0.87).

CONCLUSION

When propofol was unavailable, ketamine became a preferred ED sedation agent. Removal of propofol from the sedation armamentarium did not affect ED TAT.

Emergency medicine pharmacy practice

Emergency medicine (EM) pharmacy practice has existed for over 30 years. In recent years, however, the specialty has grown significantly. A large number of health care systems have either a dedicated EM pharmacist or other clinical pharmacist presence in the Emergency department (ED). Over the past decade, the role of the EM pharmacist as a critical member of the health care team has expanded significantly and many innovative practices have evolved throughout the country. There is also some heterogeneity between different EM pharmacy practice sites. This article reviews the history and general concepts of EM pharmacy practice as well as illustrate some of the established benefits of an EM pharmacist.

Efeitos da infusão contínua de propofol ou etomidato sobre variáveis intracranianas em cães

Avaliaram-se os efeitos da infusão contínua de propofol ou de etomidato sobre as variáveis intracranianas em cães nomocapneicos. Foram utilizados 20 cães adultos distribuídos aleatoriamente em dois grupos: grupo propofol (GP) e grupo etomidato (GE). Para o GP, os animais foram induzidos à anestesia com propofol (10mg/kg) e, ato contínuo, iniciaram-se a infusão do fármaco (0,6mg/kg/min) e a ventilação controlada. No GE, o etomidato foi usado para indução (5mg/kg) e manutenção empregando-se a dose de 0,5mg/kg/min nos 10 minutos iniciais e, em seguida, de 0,2mg/kg/min. Após 30 minutos da implantação do cateter de fibra óptica do monitor de pressão intracraniana (PIC) na superfície do córtex cerebral direito, realizaram-se as primeiras mensurações (M1) da PIC, da pressão de perfusão cerebral (PPC), da temperatura intracraniana (TIC), de temperatura corpórea (TC), da pressão arterial média (PAM) e da frequência cardíaca (FC). As demais mensurações ocorreram em intervalos de 20 minutos (M2, M3 e M4). O propofol e o etomidato não ocasionaram alterações significativas nas variáveis estudadas com exceção da TC e TIC. Concluiu-se que a infusão contínua desses fármacos em cães mantém a perfusão cerebral e a autorregulação cerebral. Cães anestesiados com etomidato apresentam efeitos adversos intensos e redução gradativa da temperatura corpórea e intracraniana.

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.

[Aspiration syndrome: epidemiology, pathophysiology, and therapy]

Aspiration syndromes are important causes of morbidity and mortality during general anaesthesia as well as in the intensive care unit. Up to 30% of patients with aspiration may develop an acute respiratory distress syndrome, with an attributed mortality of 16%. Although aspiration syndrome is not a frequent event, the anaesthesist must be familiar with the management of this complication and must know the risk factors for it. Discrimination between pneumonitis, an abacterial inflammation, and pneumonia is of utmost importance because treatment strategies differ; for instance, treatment is merely supportive in pneumonitis. This review gives an overview of the epidemiology and pathophysiology of aspiration syndrome, strategies to avoid aspiration, and a brief discussion of treatment concepts.

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.

Thiopental vs. etomidate for rapid sequence intubation in aeromedicine

INTRODUCTION

Although there is a general agreement that rapid sequence intubation (RSI) is the preferred technique for intubation in aeromedical care, several pharamacological regimens have been employed without clear evidence of which is superior.

HYPOTHESIS

This study was designed to compare the use of etomidate (ETOM) with that of thiopental (THIO) as an adjunctive agent used with succinylcholine (SCh) for RSI in an urban, aeromedical system.

METHODS

This was a retrospective, before-and-after study utilizing computer-assisted chart review. Adult patients who received THIO for RSI over a two-year period were compared to adult patients who received ETOM for RSI over a similar period, after a change in protocol, which mandated ETOM rather than THIO for all intubations.

RESULTS

No difference was found in any of the primary endpoints. Stabilization time (13.1 vs. 12.9 minutes), number of intubation attempts (1.1 vs. 1.2), successful first intubation attempts (90% vs. 82%), overall successful intubations (100% vs. 96%), and intubation time (18.4 vs. 21.7 seconds) were similar for all comparisons of THIO vs. ETOM (all p > 0.05).

CONCLUSION

This study found no clinically relevant differences between the use of ETOM or THIO as adjuncts with SCh for RSI in the aeromedical setting.

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.