Ketamine is not associated with more post-intubation hypotension than etomidate in patients undergoing endotracheal intubation

Etomidate versus ketamine for in-hospital rapid sequence intubation: a systematic review and meta-analysis

Rapid sequence intubation (RSI) is a critical procedure in emergency and intensive care settings. Etomidate has been favored for its hemodynamic stability; however, concerns about adrenal insufficiency have prompted interest in ketamine as an alternative induction agent. This systematic review and meta-analysis aimed to compare the effects of etomidate vs ketamine on 30-day survival and other clinical outcomes in critically ill patients undergoing in-hospital RSI. A comprehensive literature search was conducted until 1 November 2024, across PubMed, Embase, Web of Science, Cochrane databases, and clinical trial registries. Eligible studies included randomized controlled trials (RCTs) and controlled clinical trials (CCTs) assessing etomidate vs ketamine for RSI. The primary outcome was 30-day survival. Secondary outcomes encompassed intubation difficulty, post-intubation vasopressor use, cardiovascular collapse, Sequential Organ Failure Assessment score, systemic steroid use, organ support-free days, and adrenal insufficiency. Fourteen studies comprising 23 926 patients (19 288 receiving etomidate; 4638 receiving ketamine) met the inclusion criteria. Pooled analyses of RCTs and CCTs revealed no significant difference in 30-day survival between the two agents [RCTs: odds ratio (OR) = 0.92, 95% confidence interval (CI): 0.68-1.24, P  = 0.58; CCTs: OR = 1.16, 95% CI: 0.92-1.45, P  = 0.58]. Ketamine was associated with a higher requirement for post-intubation vasopressor support (OR = 0.71, 95% CI: 0.53-0.96, P  = 0.03) and an increase in ICU-free days. Etomidate use correlated with a significantly higher incidence of adrenal insufficiency (OR = 2.43, 95% CI: 1.67-3.53, P  < 0.001). No significant differences were observed in intubation difficulty, cardiovascular collapse, or systemic steroid use between the groups. Ketamine and etomidate showed no significant difference in 30-day survival among critically ill patients undergoing RSI. However, etomidate was associated with a higher incidence of adrenal insufficiency, while ketamine required more post-intubation vasopressor support. Provenance and peer review: Not commissioned, externally peer-reviewed.

The effect between etomidate and ketamine on peri-intubation hypotension in elderly patients in the emergency department

BACKGROUND

Peri-intubation hypotension (PIH) is associated with increased mortality. Etomidate and ketamine are commonly used as induction agents for tracheal intubation in the emergency department (ED) due to their favorable hemodynamic profiles. However, the effects of these agents on PIH remain controversial, and data on elderly patients are limited. This study aimed to compare the effects of etomidate and ketamine on PIH and 28-day mortality.

METHODS

A prospective, observational, propensity-matched cohort study was performed across two ED centers between March 23, 2022, and September 30, 2023. Patients aged 65 years and older requiring tracheal intubation and receiving either etomidate or ketamine as a single induction agent were included. The primary outcome was the incidence of PIH within 30 min post-induction, comparing etomidate and ketamine. PIH was defined as a systolic blood pressure (SBP) decrease of more than 20 % from baseline, SBP <100 mmHg (with or without fluid resuscitation), or the initiation or increased dose of vasopressor therapy. Secondary outcomes included 28-day mortality and subgroup analysis evaluating the effect of induction dose on PIH in patients with a shock index (SI) ≥0.9. Statistical analyses included a chi-square test to compare PIH incidence and Cox regression analysis to assess the association between induction agents and 28-day mortality. Multivariable Cox regression was adjusted for mortality by vasopressor initiation or escalation. Fractional polynomial regression was used to evaluate the relationship between induction agent dose and PIH.

RESULTS

A total of 418 patients were included in the analysis, with 222 patients matched in a 1:1 propensity score analysis. The incidence of PIH was 44.1 % in the etomidate group and 53.2 % in the ketamine group (risk difference 9.1 %, 95 % confidence interval [CI] -4.1 to 22.1, p = 0.179). 28-day mortality was 36.0 % in the etomidate group and 25.2 % in the ketamine group (hazard ratio [HR] 0.66, 95 % CI 0.41-1.07, p = 0.095). However, in patients who developed PIH and required vasopressors, ketamine was associated with a lower risk of 28-day mortality (adjusted HR 0.59, 95 % CI 0.36-0.97, p = 0.034). Among patients with SI ≥0.9, a higher induction agent dose was associated with an increased probability of PIH for both etomidate and ketamine.

CONCLUSION

There was no statistically significant difference in PIH and 28-day mortality between etomidate and ketamine as a single induction agent in elderly patients in the ED.

Incidence of post-induction hypotension following emergency rapid sequence induction with ketamine: a systematic review and meta-analysis

INTRODUCTION

Rapid sequence induction (RSI) is a potentially-life saving intervention in critically ill patients. An important adverse effect of this procedure is post-induction hypotension (PIH), which is associated with worsened patient outcomes. Choice of induction agent can affect incidence of PIH, although the optimal drug has yet to be determined. Ketamine is postulated to reduce PIH incidence in emergency RSI when used instead of alternative agents.

AIMS

This systematic review and meta-analysis aims to evaluate the effect on PIH incidence of inducing anaesthesia with ketamine during emergency RSI.

METHODS

A systematic search was conducted to identify a sample of studies fulfilling criteria for population (emergency RSI), intervention (ketamine), comparator (any alternative induction agent) and outcome (PIH). No single definition of PIH was required for eligibility. A random-effects model was used to produce a pooled effect size estimate from the extracted data. The study question was also tested in pre-specified subgroups, including by specific comparator induction agent and by indication for RSI (medical vs trauma).

RESULTS

27 studies, including 6 randomised controlled trials, were eligible for inclusion, with total n = 31,956. There was considerable methodological heterogeneity. The pooled estimate of odds ratio (OR) of PIH when ketamine is used for emergency RSI is 1.10, with 95% confidence interval 0.78-1.56. Excluding data from the 6 studies (1 randomised and 5 observational) at greater risk of bias, the pooled OR is 0.99 (0.69-1.43). There was no significant difference between ketamine and comparators in any subgroup, although significance was approached when comparing ketamine to etomidate, with OR 1.38 (0.99-1.94) and p = 0.058.

CONCLUSIONS

Choice of ketamine to carry out emergency RSI did not affect the incidence of PIH incidence in this diverse sample of studies. Given the breadth of inclusion criteria, applicability of this result is not necessarily universal. It is likely that optimal choice of induction agent varies according to specific circumstances in a manner as yet incompletely understood.

Post-induction hypotension during rapid sequence intubation in the operating room: A post hoc analysis of the randomized controlled REMICRUSH trial

BACKGROUND

We explored the risk factors of post-induction hypotension during rapid sequence intubation.

METHODS

We performed an ancillary analysis of a multicenter randomized clinical trial comparing remifentanil versus neuromuscular blockers associated with hypnotic in patients at risk for aspiration who underwent tracheal intubation in the operating room. The primary outcome was post-induction hypotension, defined as an episode of hypotension (MBP ≤ 55 mmHg and/or SBP ≤ 80 mmHg) within 10 min after anesthetic induction.

RESULTS

From 15 hospitals, 1137 adult patients were included, and 291 (26%) had post-induction hypotension. Propofol was used in 1117 (98%) patients and was associated with low doses of ketamine in 209 (18 %) patients. The independent risk factors associated with post-induction hypotension were age (OR 1.03, 95% CI [1.02; 1.04] p < 0.0001), baseline heart rate (p = 0.0068), bowel occlusion requiring nasogastric tube placement before intubation (OR 1.96, 95% CI [1.33; 2.87] p = 0.0006) and use of remifentanil (OR 3.54, 95%CI (2.61; 4.81) p < 0.0001). Use of low doses of ketamine (OR 0.61, 95% CI [0.41; 0.92] p = 0.0175) and basal SBP (OR 0.98, 95% CI [0.97; 0.99] p < 0.0001) were protective factors. The precision of the final model including the above-mentioned variables gave an AUC of 0.74 [95% CI 0.71; 0.77] for post-induction hypotension prediction.

CONCLUSIONS

Post-induction hypotension was frequent during rapid sequence intubation. Sedation associating propofol with low doses of ketamine was associated with a low risk of post-induction hypotension. Further studies are required to demonstrate a causal effect.

REGISTRATION

ClinicalTrials.gov NCT03960801.

Postintubation hypotension following rapid sequence intubation with full- vs reduced-dose induction agent

PURPOSE

Rapid sequence intubation (RSI) is a common emergency department (ED) procedure with an associated complication of postintubation hypotension (PIH). It has not been clearly established whether the selection and dose of induction agent affect risk of PIH. The objective of this study was to determine the incidence of PIH in patients receiving full-dose compared to reduced-dose induction agent for RSI in the ED.

METHODS

This was a health system-wide, retrospective cohort study comparing incidence of PIH based on the induction medication and dose given for RSI in the ED. Patients were included if they underwent RSI from July 1, 2018, through December 31, 2020, were 18 years of age or older, and received etomidate or ketamine. A reduced dose was defined as a ketamine dose of 1.25 mg/kg or less and an etomidate dose of 0.2 mg/kg or less.

RESULTS

A total of 909 patients were included in the final analysis, with most receiving etomidate (n = 764; 84%) and a smaller number receiving ketamine (n = 145; 16%). Patients who received ketamine had a higher mean pre-intubation shock index (full dose, 1.08; reduced dose, 1.04) than those who received etomidate (full dose, 0.89; reduced dose, 0.92) (P ≤ 0.001). Reduced doses of induction agent were observed for 107 patients receiving etomidate (14.0%) and 60 patients receiving ketamine (41.4%). Patients who received full-dose ketamine for induction had the highest rate of PIH (n = 31; 36.5%), and the difference was statistically significant compared to patients receiving reduced-dose ketamine (16.7%; P = 0.021) and full-dose etomidate (22.8%; P = 0.010).

CONCLUSION

We observed that full-dose ketamine was associated with the highest rate of PIH; however, this group had the poorest baseline hemodynamics, confounding interpretation. Our results do not support broad use of a reduced-dose induction agent.

The Importance of Circulation in Airway Management: Preventing Postintubation Hypotension in the Trauma Bay

OBJECTIVE

To identify the modifiable and nonmodifiable risk factors associated with postintubation hypotension (PIH) among trauma patients who required endotracheal intubation (ETI) in the trauma bay.

BACKGROUND

ETI has been associated with hemodynamic instability, termed PIH, yet its risk factors in trauma patients remain underinvestigated.

METHODS

This is a prospective observational study at a level I trauma center over 4 years (2019-2022). All adult (≥18) trauma patients requiring ETI in the trauma bay were included. Blood pressure was monitored both preintubation and postintubation. Multivariable logistic regression analysis was performed to identify the modifiable and nonmodifiable factors associated with PIH.

RESULTS

Seven hundred eight patients required ETI in the trauma bay, of which, 435 (61.4%) developed PIH. The mean (SD) age was 43 (21) years and 71% were male. Median [interquartile range] arrival Glasgow Coma Scale was 7 [3-13]. Patients who developed PIH had a lower mean (SD) preintubation systolic blood pressure [118 (46) vs 138 (28), P <0.001] and higher median [interquartile range] Injury Severity Score: 27 [21-38] versus 21 [9-26], P <0.001. Multivariable regression analysis identified body mass index >25, increasing Injury Severity Score, penetrating injury, spinal cord injury, preintubation packed red blood cell requirements, and diabetes mellitus as nonmodifiable risk factors associated with increased odds of PIH. In contrast, preintubation administration of 3% hypertonic saline and vasopressors were identified as the modifiable factors significantly associated with reduced PIH.

CONCLUSIONS

More than half of the patients requiring ETI in the trauma bay developed PIH. This study identified modifiable and nonmodifiable risk factors that influence the development of PIH, which will help physicians when considering ETI upon patient arrival.

LEVEL OF EVIDENCE

Level III-Prognostic study.

Evaluation of Reduced-Dose Induction Agents During Endotracheal Intubation in Critical Care Transport

OBJECTIVE

Induction agent selection and dose are potentially modifiable risk factors to mitigate postintubation hypotension and hemodynamic collapse. Despite it being a common practice, minimal literature exists to support induction agent dose reduction. Our objective was to evaluate the rate of postintubation hemodynamic collapse with reduced-dose compared to full dose induction agents.

METHODS

This is a retrospective chart review of adult patients who were endotracheally intubated by a critical care transport team and received etomidate or ketamine for induction. The primary outcome was association of reduced-dose induction agent use (etomidate <0.2 mg/kg or ketamine <1 mg/kg) with postintubation hemodynamic collapse.

RESULTS

A total of 304 patients were included; 187 (61.5%) received etomidate and 117 (38.5%) received ketamine. Of these 304 patients, 64 (21.1%) received reduced-dose agents and 240 (78.9%) received full-dose agents. The initial systolic blood pressure and mean arterial blood pressure levels were lower in the reduced-dose arm. Shock index, hemodynamic collapse, and life-threatening hemodynamic collapse did not differ between the groups.

CONCLUSION

In this analysis, there was no difference in rates of postintubation hemodynamic collapse with reduced-dose induction agents when compared with full-dose agents.

The use of vasopressors to reduce post-intubation hypotension in critically ill adult patients undergoing emergent endotracheal intubation: a scoping review

INTRODUCTION

Patients requiring emergent endotracheal intubation are at higher risk of post-intubation hypotension due to altered physiology in critical illness. Post-intubation hypotension increases mortality and hospital length of stay, however, the impact of vasopressors on its incidence and outcomes is not known. This scoping review identified studies reporting hemodynamic data in patients undergoing emergent intubation to provide a literature overview on post-intubation hypotension in cohorts that did and did not receive vasopressors.

METHODS

A systematic search of CINAHL, Cochrane, EMBASE and PubMed-Medline was performed from database inception until September 28, 2023. Two independent reviewers completed the title and abstract screen, full text review and data extraction per PRISMA guidelines. Studies including patients < 18 years or intubations during cardiac arrest were excluded. Primary outcome was the presence of hypotension within 30 min of emergent intubation. Secondary outcomes included mortality at 1 h and in-hospital.

RESULTS

The systematic search yielded 13,126 articles, with 61 selected for final inclusion. There were 24,547 patients with a mean age of 57.2 years and a slight male predominance (63.8%). Respiratory failure was the most common intubation indication. Across 18 studies reporting on vasopressor use prior to intubation, 1171/7085 patients received vasopressors pre-intubation. Post-intubation hypotension occurred in 22.2% of patients across all studies, and in 34.3% of patients in studies where vasopressor administration pre-intubation was specifically reported. One-hour mortality of patients across all studies and within the vasopressor use studies was 1.2% and 1.6%, respectively. In-hospital mortality across studies was 21.5%, and 13.1% in studies which reported on vasopressor use pre-intubation.

CONCLUSION

Patients requiring emergent intubation have a high rate of post-intubation hypotension and in-hospital mortality. While there is an intuitive rationale for the use of vasopressors during emergent intubation, current evidence is limited to support a definitive change in clinical practice at this time.

The impact of ketamine on emergency rapid sequence intubation: a systematic review and meta-analysis

BACKGROUND

Rapid sequence intubation (RSI) is a crucial step in the resuscitation process for critically ill patients, and the judicious use of sedative drugs during RSI significantly influences the clinical outcomes of patients. Ketamine is a commonly used anesthetic sedative; however, its impact on the mortality of patients undergoing RSI has yielded inconsistent findings. Therefore, we conducted a systematic review and meta-analysis investigating ketamine's role in RSI to provide insights into selecting appropriate sedatives for critically ill patients.

METHODS

In this systematic review and meta-analysis, we conducted a systematic search on MEDLINE (PubMed), Embase, and Cochrane Central Register of Controlled Trials, without restricting to randomized controlled trials (RCTs) or cohort studies. The search was performed from inception until Dec 12, 2023, with no language restrictions. All studies comparing the use of sedatives, including ketamine, and documenting in-hospital mortality were included in this study.

RESULTS

A total of 991 studies were identified, out of which 15 studies (5 RCTs and 10 cohort studies) involving 16,807 participants fulfilled the inclusion criteria. No significant impact on in-hospital mortality was observed with the use of ketamine compared to other drugs during RSI (OR 0.90, 95%CI 0.72 to 1.12). Low-quality evidence suggested that ketamine might reduce mortality within the first seven days of hospitalization (OR 0.42, 95%CI 0.19 to 0.93), but it may also have a potential effect on prolonging ICU-free days at day 28 (MD -0.71, 95%CI -1.38 to -0.05). There were no significant differences in the results of the other RSI-related outcomes, such as physiological function and adverse events.

CONCLUSIONS

Based on existing studies, ketamine showed no significant difference compared to other sedatives in terms of in-hospital mortality, physiological impact, and side effects following RSI. However, it may reduce mortality within 7 days while probably prolong the length of stay in the ICU.

TRIAL REGISTRATION

CRD42023478020.

Exploring the Role of Ketamine Sedation in Critically Ill Patients: A Comprehensive Review

Sedation management in critically ill patients is a critical component of intensive care, aiming to balance the need for comfort and immobilization with preserving vital physiological functions. Ketamine, known for its dissociative anesthetic properties, has emerged as a promising alternative to traditional sedatives due to its unique pharmacological profile. This review explores the pharmacodynamics, clinical applications, benefits, challenges, and current evidence surrounding ketamine as a sedative agent in intensive care settings. Key advantages of ketamine include its ability to maintain respiratory drive and hemodynamic stability, making it particularly suitable for patients requiring continuous monitoring and intervention. The review discusses its role in sedation protocols, compares its effectiveness with other sedatives, and highlights potential areas for further research and optimization. By elucidating the complexities and advancements in ketamine sedation, this review aims to inform clinical practice and contribute to improved outcomes for critically ill patients.

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.

A Nomogram Model for Post-Intubation Hypotension in Patients with Severe Pneumonia in the Emergency Department

Background

Post-intubation hypotension (PIH) frequently occurs in the management of critically ill patients and is associated with prognosis. The study aimed to construct a prediction model for PIH events by analyzing risk factors in patients with severe pneumonia in the emergency department.

Methods

We retrospectively enrolled 572 patients with severe pneumonia diagnosed in the emergency department of West China Hospital of Sichuan University. Five hundred patients with severe pneumonia who underwent endotracheal intubation were included in the study. All patients were randomized according to 7:3 and divided into a training cohort (n=351) and a validation cohort (n=149). Risk factors for PIH were analyzed using Least Absolute Shrinkage and Selection Operator (LASSO) and multivariable logistic regression. Calibration curves, receiver operating characteristic (ROC) curve, and decision curve analysis were applied to assess the predictive model's fitness, discrimination, and clinical utility.

Results

A total of 500 patients with severe pneumonia who underwent endotracheal intubation were enrolled in this study, and PIH occurred in 234 (46.8%) of these patients. Age, heart rate, systolic blood pressure, chronic obstructive pulmonary disease, acute physiology and chronic health evaluation II score, and induction agent use were identified as significant risk factors for the occurrence of PIH. Additionally, the body mass index was the opposite of the above. The area under the ROC curve (AUC) for the model was 0.856 (95% CI, 0.818-0.894) in the training cohort and 0.849 (95% CI, 0.788-0.910) in the validation cohort. The nomogram model was validated and demonstrated good calibration and high net clinical benefit. Finally, to facilitate application by clinicians, an online server has been set up which can be accessed free of charge via the website https://chinahospitals.shinyapps.io/DynNomapp/.

Conclusion

The nomogram is used for individualized prediction of patients with severe pneumonia prior to intubation and is simple to perform with high clinical value.

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.