Etomidate Compared to Ketamine for Induction during Rapid Sequence Intubation: A Systematic Review and Meta-analysis

Etomidate versus Ketamine as Prehospital Induction Agent in Patients with Suspected Severe Traumatic Brain Injury

BACKGROUND

Severe traumatic brain injury is a leading cause of morbidity and mortality among young people around the world. Prehospital care focuses on the prevention and treatment of secondary brain injury and commonly includes tracheal intubation after induction of general anesthesia. The choice of induction agent in this setting is controversial. This study therefore investigated the association between the chosen induction medication etomidate versus S(+)-ketamine and the 30-day mortality in patients with severe traumatic brain injury who received prehospital airway management in the Netherlands.

METHODS

This study is a retrospective analysis of the prospectively collected observational data of the Brain Injury: Prehospital Registry of Outcomes, Treatments and Epidemiology of Cerebral Trauma (BRAIN-PROTECT) cohort study. Patients with suspected severe traumatic brain injury who were transported to a participating trauma center and who received etomidate or S(+)-ketamine for prehospital induction of anesthesia for advanced airway management were included. Statistical analyses were performed with multivariable logistic regression and inverse probability of treatment weighting analysis.

RESULTS

In total, 1,457 patients were eligible for analysis. No significant association between the administered induction medication and 30-day mortality was observed in unadjusted analyses (32.9% mortality for etomidate versus 33.8% mortality for S(+)-ketamine; P = 0.716; odds ratio, 1.04; 95% CI, 0.83 to 1.32; P = 0.711), as well as after adjustment for potential confounders (odds ratio, 1.08; 95% CI, 0.67 to 1.73; P = 0.765; and risk difference 0.017; 95% CI, -0.051 to 0.084; P = 0.686). Likewise, in planned subgroup analyses for patients with confirmed traumatic brain injury and patients with isolated traumatic brain injury, no significant differences were found. Consistent results were found after multiple imputations of missing data.

CONCLUSIONS

The analysis found no evidence for an association between the use of etomidate or S(+)-ketamine as an anesthetic agent for intubation in patients with traumatic brain injury and mortality after 30 days in the prehospital setting, suggesting that the choice of induction agent may not influence the patient mortality rate in this population.

EDITOR’S PERSPECTIVE

Ketamine Efficacy for Management of Status Epilepticus: Considerations for Prehospital Clinicians

Current first-line therapies for seizure management recommend benzodiazepines, which target gamma-aminobutyric acid type A channels to stop the seizure activity. However, seizures may be refractory to traditional first-line therapies, transitioning into status epilepticus and becoming resistant to gamma-aminobutyric acid type A augmenting drugs. Although there are other antiseizure medications available for clinicians to use in the intensive care unit, these options can be less readily available outside of the intensive care unit and entirely absent in the prehospital setting. Instead, patients frequently receive multiple doses of first-line agents with increased risk of hemodynamic or airway collapse. Ketamine is readily available in the prehospital setting and emergency department, has well-established antiseizure effects with a favorable safety profile, and is a drug often used for several other indications. This article aimed to explore the utilization of ketamine for seizure management in the prehospital setting, reviewing seizure pathophysiology, established treatment mechanisms of action and pharmacokinetics, and potential benefits of early ketamine use in status epilepticus.

Ketamine versus etomidate as an induction agent for tracheal intubation in critically ill adults: a Bayesian meta-analysis

BACKGROUND

Tracheal intubation is a high-risk intervention commonly performed in critically ill patients. Due to its favorable cardiovascular profile, ketamine is considered less likely to compromise clinical outcomes. This meta-analysis aimed to assess whether ketamine, compared with other agents, reduces mortality in critically ill patients undergoing intubation.

METHODS

We searched MEDLINE, Embase, and the Cochrane Library from inception until April 27, 2023, for randomized controlled trials and matched observational studies comparing ketamine with any control in critically ill patients as an induction agent. The primary outcome was mortality at the longest follow-up available, and the secondary outcomes included Sequential Organ Failure Assessment score, ventilator-free days at day 28, vasopressor-free days at day 28, post-induction mean arterial pressure, and successful intubation on the first attempt. For the primary outcome, we used a Bayesian random-effects meta-analysis on the risk ratio (RR) scale with a weakly informative neutral prior corresponding to a mean estimate of no difference with 95% probability; the estimated effect size will fall between a relative risk of 0.25 and 4. The RR and 95% credible interval (CrI) were used to estimate the probability of mortality reduction (RR < 1). The secondary outcomes were assessed with a frequentist random-effects model. We registered this study in Open Science Framework ( https://osf.io/2vf79/ ).

RESULTS

We included seven randomized trials and one propensity-matched study totaling 2978 patients. Etomidate was the comparator in all the identified studies. The probability that ketamine reduced mortality was 83.2% (376/1475 [25%] vs. 411/1503 [27%]; RR, 0.93; 95% CrI, 0.79-1.08), which was confirmed by a subgroup analysis excluding studies with a high risk of bias. No significant difference was observed in any secondary outcomes.

CONCLUSIONS

All of the included studies evaluated ketamine versus etomidate among critically ill adults requiring tracheal intubation. This meta-analysis showed a moderate probability that induction with ketamine is associated with a reduced risk of mortality.

Spanish Society of Anesthesiology, Reanimation and Pain Therapy (SEDAR), Spanish Society of Emergency and Emergency Medicine (SEMES) and Spanish Society of Otolaryngology, Head and Neck Surgery (SEORL-CCC) Guideline for difficult airway management

The Airway Management section of the Spanish Society of Anesthesiology, Resuscitation, and Pain Therapy (SEDAR), the Spanish Society of Emergency Medicine (SEMES), and the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC) present the Guide for the comprehensive management of difficult airway in adult patients. Its principles are focused on the human factor, cognitive processes for decision-making in critical situations, and optimization in the progression of strategies application to preserve adequate alveolar oxygenation in order to enhance safety and the quality of care. The document provides evidence-based recommendations, theoretical-educational tools, and implementation tools, mainly cognitive aids, applicable to airway management in the fields of anesthesiology, critical care, emergencies, and prehospital medicine. For this purpose, an extensive literature search was conducted following PRISMA-R guidelines and was analyzed using the GRADE methodology. Recommendations were formulated according to the GRADE methodology. Recommendations for sections with low-quality evidence were based on expert opinion through consensus reached via a Delphi questionnaire.

Factors Associated with Postintubation Hypotension Among Patients with Suspected Sepsis in Emergency Department

Purpose

Postintubation hypotension (PIH) is a recognized complication that increases both in-hospital mortality and hospital length of stay. Sepsis is reportedly a factor associated with PIH. However, no study to date has examined which factors, including the intubation method, may be clinical predictors of PIH in patients with sepsis. This study aims to investigate factors associated with the occurrence of PIH in patients with suspected sepsis in emergency department.

Patients and Methods

This retrospective cross-sectional study was performed over a 5-year period (January 2013-December 2017) and involved patients with suspected sepsis who underwent endotracheal intubation in the emergency department of Ramathibodi Hospital. The patients were divided into those with and without PIH, and factors associated with the occurrence of PIH were analyzed. PIH was defined as any recorded systolic blood pressure of <90 mmHg within 60 minutes of intubation.

Results

In total, 394 patients with suspected sepsis were included. PIH occurred in 106 patients (26.9%) and was associated with increased in-hospital mortality (43.00% in the PIH group vs 31.25% in the non-PIH group, P = 0.034). Multivariable logistic regression showed that the factors associated with PIH were an age of ≥61 years (adjusted odds ratio [aOR] 2.25; 95% confidence interval [CI] 1.14-4.43; P = 0.019) and initial serum lactate concentration of >4.4 mmol/L (aOR 2.00; 95% CI 1.16-3.46; P = 0.013). Rapid sequence intubation and difference types of induction agents was unrelated to PIH.

Conclusion

Monitoring the development of PIH in patients with sepsis is essential because of its correlation with higher in-hospital mortality. This is particularly critical for older individuals and those with severe infections and high initial lactate concentrations.

Evolving Techniques in RSI: Can the Choice of Induction Agent Matter in Securing a Definitive Airway in Emergency Settings?

How to cite this article: George B, Joachim N. Evolving Techniques in RSI: Can the Choice of Induction Agent Matter in Securing a Definitive Airway in Emergency Settings? Indian J Crit Care Med 2022;26(1):15-17.