Etomidate is associated with mortality and adrenal insufficiency in sepsis: A meta-analysis*

Rapid Sequence Intubation, is it Time to Find an Alternative Induction Agent? A Narrative Review

Objective: To review the efficacy, safety, and place in therapy of fentanyl as an induction agent for rapid sequence intubation (RSI) in critically ill patients. Data Sources: A comprehensive search of PubMed, EMBASE, and clinical trial registries (1964-June 2021) was performed utilizing the keywords fentanyl, rapid sequence intubation, intubation, induction, anesthesia, hemodynamics, operating room (OR), and emergency. Study Selection and Data Extraction: Only primary literature evaluating fentanyl in combination with a sedative or as the sole induction agent was included in the final analysis. Primary literature included peer-reviewed publications and results posted on ClinicalTrials.gov actively recruiting participants. Data Synthesis: Fentanyl has been used for decades as an adjunct, and sole induction agent in the OR. Questions surrounding the use of fentanyl as a sole induction agent include optimal dosing and safety in critically ill patients as evaluation in non-OR settings remain limited. Relevance to Patient Care and Clinical Practice: Commonly used induction agents (eg, etomidate and ketamine) are associated with adverse events that may increase risk of morbidity and mortality. Fentanyl, a high-potency opioid could serve as an alternative induction agent for RSI due to its neutral hemodynamic response and fast onset of action. This paper compiles and describes existing data on the use of fentanyl as an induction agent for RSI. Conclusion: Fentanyl in combination with sedatives provides optimal intubating conditions with minimal impact on hemodynamic parameters. Future studies should focus on safety and impact of awareness during paralysis before fentanyl can be considered as a sole induction agent.

Extra-cardiac management of cardiogenic shock in the intensive care unit

Cardiogenic shock (CS) is a heterogeneous clinical syndrome characterized by low cardiac output leading to end-organ hypoperfusion. Organ dysoxia ranging from transient organ injury to irreversible organ failure and death occurs across all CS etiologies but differing by incidence and type. Herein, we review the recognition and management of respiratory, renal and hepatic failure complicating CS. We also discuss unmet needs in the CS care pathway and future research priorities for generating evidence-based best practices for the management of extra-cardiac sequelae. The complexity of CS admitted to the contemporary cardiac intensive care unit demands a workforce skilled to care for these extra-cardiac critical illness complications with an appreciation for how cardio-systemic interactions influence critical illness outcomes in afflicted patients.

Propofol vs etomidate for induction prior to invasive mechanical ventilation in patients with acute myocardial infarction

BACKGROUND

Patients with acute myocardial infarction (AMI) requiring invasive mechanical ventilation (IMV) have a high mortality. However, little is known regarding the impact of induction agents, used prior to IMV, on clinical outcomes in this population. We assessed for the association between induction agent and mortality in patients with AMI requiring IMV.

METHODS

We compared clinical outcomes between those receiving propofol compared to etomidate for induction among adults with AMI between October 2015 and December 2019 using the Vizient® Clinical Data Base, a multicenter, US national database. We used inverse probability treatment weighting (IPTW) to assess for the association between induction agent and in-hospital mortality.

RESULTS

We identified 5,147 patients, 1,386 (26.9%) of received propofol and 3,761 (73.1%) received etomidate for IMV induction. The mean (SD) age was 66.1 (12.4) years, 33.0% were women, and 51.6% and 39.8% presented with STEMI and cardiogenic shock, respectively. Patients in the propofol group were more likely to require preintubation vasoactive medication and mechanical circulatory support (both, P < .05). Utilization of propofol was associated with lower mortality compared to etomidate (32.3% vs 36.1%, P = .01). After propensity weighting, propofol use remained associated with lower mortality (weighted mean difference -4.7%; 95% confidence interval: -7.6% to -1.8%, P = .002). Total cost, ventilator days, and length of stay were higher in the propofol group (all, P < .001).

CONCLUSIONS

Induction with propofol, compared with etomidate, was associated with lower mortality for patients with AMI requiring IMV. Randomized trials are needed to determine the optimal induction agent for this critically ill patient population.

Understanding the Physiological Connection: Cardiac Arrest Following Prone Positioning

Prone positioning of patients is a routine occurrence in procedural suites and operating rooms (ORs). However, the physiological changes that occur with prone positioning are frequently underappreciated by proceduralists, surgeons, and anesthesiologists. This may be related to a sense of the routine or a lack of familiarity with physiological changes that accompany the prone position. The prone position, while aiding visualization and cannulation of the ampulla of Vater during endoscopic retrograde cholangiopancreatography (ERCP), can induce physiological changes such as reduced preload, inferior vena cava filling, and cardiac output; it can also increase intrathoracic pressure and mediastinal compression. Anesthetic agents can further impact cardiopulmonary physiology, decreasing systemic vascular resistance and reducing cardiac contractility. In addition, the transition from negative to positive pressure ventilation following endotracheal intubation can increase pulmonary artery pressures and right ventricular (RV) strain. Therefore, caution is needed with patients who have RV dysfunction, pulmonary hypertension, or preload dependency, as they may not tolerate prone positioning. We describe a case in which a 73-year-old male patient scheduled for an ERCP suffered cardiac arrest after being transitioned to the prone position. The patient was repositioned in the supine position and resuscitated. The case was completed in the supine position.

Problematic meta-analyses: Bayesian and frequentist perspectives on combining randomized controlled trials and non-randomized studies

PURPOSE

In the literature, the propriety of the meta-analytic treatment-effect produced by combining randomized controlled trials (RCT) and non-randomized studies (NRS) is questioned, given the inherent confounding in NRS that may bias the meta-analysis. The current study compared an implicitly principled pooled Bayesian meta-analytic treatment-effect with that of frequentist pooling of RCT and NRS to determine how well each approach handled the NRS bias.

MATERIALS & METHODS

Binary outcome Critical-Care meta-analyses, reflecting the importance of such outcomes in Critical-Care practice, combining RCT and NRS were identified electronically. Bayesian pooled treatment-effect and 95% credible-intervals (BCrI), posterior model probabilities indicating model plausibility and Bayes-factors (BF) were estimated using an informative heavy-tailed heterogeneity prior (half-Cauchy). Preference for pooling of RCT and NRS was indicated for Bayes-factors > 3 or < 0.333 for the converse. All pooled frequentist treatment-effects and 95% confidence intervals (FCI) were re-estimated using the popular DerSimonian-Laird (DSL) random effects model.

RESULTS

Fifty meta-analyses were identified (2009-2021), reporting pooled estimates in 44; 29 were pharmaceutical-therapeutic and 21 were non-pharmaceutical therapeutic. Re-computed pooled DSL FCI excluded the null (OR or RR = 1) in 86% (43/50). In 18 meta-analyses there was an agreement between FCI and BCrI in excluding the null. In 23 meta-analyses where FCI excluded the null, BCrI embraced the null. BF supported a pooled model in 27 meta-analyses and separate models in 4. The highest density of the posterior model probabilities for 0.333 < Bayes factor < 1 was 0.8.

CONCLUSIONS

In the current meta-analytic cohort, an integrated and multifaceted Bayesian approach gave support to including NRS in a pooled-estimate model. Conversely, caution should attend the reporting of naïve frequentist pooled, RCT and NRS, meta-analytic treatment effects.

Nanotherapeutics for Alleviating Anesthesia-Associated Complications

Current management of anesthesia-associated complications falls short in terms of both efficacy and safety. Nanomaterials with versatile properties and unique nano-bio interactions hold substantial promise as therapeutics for addressing these complications. This review conducts a thorough examination of the existing nanotherapeutics and highlights the strategies for developing prospective nanomedicines to mitigate anesthetics-related toxicity. Initially, general, regional, and local anesthesia along with the commonly used anesthetics and related prevalent side effects are introduced. Furthermore, employing nanotechnology to prevent and alleviate the complications of anesthetics is systematically demonstrated from three aspects, that is, developing 1) safe nano-formulization for anesthetics; 2) nano-antidotes to sequester overdosed anesthetics and alter their pharmacokinetics; 3) nanomedicines with pharmacodynamic activities to treat anesthetics toxicity. Finally, the prospects and challenges facing the clinical translation of nanotherapeutics for anesthesia-related complications are discussed. This work provides a comprehensive roadmap for developing effective nanotherapeutics to prevent and mitigate anesthesia-associated toxicity, which can potentially revolutionize the management of anesthesia complications.

The effects of etomidate on expression of high mobility group box 1 via the nuclear factor kappa B pathway in rat model of sepsis

Etomidate is an anesthetic agent used in hemodynamically unstable patients, but its use has been controversial in septic patients. The response of high-mobility group box 1 (HMGB1), a late-phase lethal cytokine in sepsis, to etomidate has not been reported. This study investigated the effects of etomidate on the expression and release of HMGB1 and the underlying mechanism using a cecal ligation and puncture (CLP) model. Thirty-six male Sprague-Dawley rats were divided into sham, CLP, and Etomi groups. Sepsis was induced in the CLP and Etomi groups, and intravenous etomidate (4 mg/kg) was infused for 40 min immediately after operation in the Etomi group. Serum creatinine, alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and HMGB1 levels were measured 6 and 24 hours after surgery. Activation of nuclear factor (NF)-ĸB and HMGB1 mRNA expression in the liver, lung, kidney, and ileum tissues were measured, and immunohistochemical staining of HMGB1 was implemented. Increases of the TNF-α level 6 h after CLP and ALT and IL-6 levels 24 h after CLP were significantly inhibited by etomidate treatment. Etomidate treatment also significantly attenuated the increase in serum HMGB1 level at 6 and 24 h after CLP and suppressed the NF-ĸB and HMGB1 mRNA in multiple organs 24 h after CLP. Immunohistochemical staining also revealed that etomidate treatment inhibited HMGB1 expression. Etomidate inhibited the systemic release of HMGB1 and its expression in various organs. The mechanism may be associated with the inhibitory effects of etomidate on pro-inflammatory cytokine release and NF-ĸB activity.

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.

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.

Effect of Anesthesia Induction on Cardiac Hemodynamics in Patients Undergoing Durable Left Ventricular Assist Device Implantation: The EACH-LVAD Study

Right ventricular (RV) dysfunction is common after left ventricular assist device (LVAD) implantation leading to clinical right heart failure (RHF) associated with worsened survival and quality of life. It is likely that intraoperative events such as anesthesia induction play a role in the development or unmasking of RV dysfunction in addition to known effects from hemodynamic changes that occur after LVAD implantation. The EACH-LVAD Study is a prospective, single-center, single-arm, observational cohort study of adult patients with advanced heart failure undergoing durable LVAD implantation with standard anesthesia induction. Intraoperative RV hemodynamics via central venous pressure, mean pulmonary artery pressure, pulmonary artery pulsatility index, and vasoactive-inotropic score (a simple weighted summation of standardized drug doses) and echocardiographic parameters (RV fractional area change, RV area in diastole, RV basal diameter, septum position, RV function, tricuspid regurgitation) were measured and compared at prespecified timepoints, including postinduction. Postoperative clinical RHF was determined based on published definitions. Forty-two patients receiving a first-time LVAD were included between September 2017 and March 2019. Propofol-based induction was used in 31 patients and etomidate-based induction in eight patients. A significant increase in central venous pressure (CVP; p < 0.001), mean pulmonary artery pressure (mPAP; p < 0.001), and vasoactive inotropic score (VIS; p < 0.001) with associated decrease in pulmonary artery pulsatility index (PAPi; p < 0.001) was observed. Right ventricular function worsened throughout. Right heart failure occurred in 70% of patients. Propofol-based induction was not associated with a higher risk of RHF (relative risk [RR], 1.01 [95% confidence interval {CI}, 0.64-1.61]). The EACH-LVAD study demonstrates an effect of anesthesia induction on worsened RV hemodynamics and echocardiographic changes which may have an effect on the development of RHF.

Clinical outcomes after a single induction dose of etomidate versus ketamine for emergency department sepsis intubation: a randomized controlled trial

Patients with sepsis often require emergency intubation. In emergency departments (EDs), rapid-sequence intubation with a single-dose induction agent is standard practice, but the best choice of induction agent in sepsis remains controversial. We conducted a randomized, controlled, single-blind trial in the ED. We included septic patients who were aged at least 18 years and required sedation for emergency intubation. Patients were randomly assigned by a blocked randomization to receive 0.2-0.3 mg/kg of etomidate or 1-2 mg/kg of ketamine for intubation. The objectives were to compare the survival outcomes and adverse events after intubation between etomidate and ketamine. Two hundred and sixty septic patients were enrolled; 130 patients/drug arm whose baseline characteristics were well balanced at baseline. In the etomidate group, 105 patients (80.8%) were alive at 28 days, compared with 95 patients (73.1%) in the ketamine group (risk difference [RD], 7.7%; 95% confidence interval [CI], - 2.5 to 17.9%; P = 0.092). There was no significant difference in the proportion of patients who survived at 24 h (91.5% vs. 96.2%; P = 0.097) and survived at 7 days (87.7% vs. 87.7%; P = 0.574). A significantly higher proportion of the etomidate group needed a vasopressor within 24 h after intubation: 43.9% vs. 17.7%, RD, 26.2% (95% CI, 15.4 to 36.9%; P < 0.001). In conclusion, there were no differences in early and late survival rates between etomidate and ketamine. However, etomidate was associated with higher risks of early vasopressor use after intubation. Trial registration: The trial protocol was registered in the Thai Clinical Trials Registry (identification number: TCTR20210213001). Registered 13 February 2021-Retrospectively registered, https://www.thaiclinicaltrials.org/export/pdf/TCTR20210213001 .

Associations of Betatrophin/ANGPTL8 with Septic Dyslipidemia in Human Peritonitis: An Explorative Analysis

Sepsis is defined by life-threatening organ dysfunction mediated by the host’s response to infection. This can result in septic dyslipidemia, which is involved in the neutralization of pathogen-related lipids. Knowledge of the regulatory mechanisms of septic dyslipidemia is incomplete. The cytokine betatrophin/Angiopoietin-like protein 8 (ANGPTL8) plays a role in the regulation of triacylglyceride metabolism, though its function in septic dyslipidemia remains unknown. Sixty-six patients were enrolled in a cross-sectional study. Circulating concentrations and adipose tissue (AT) mRNA expression of betatrophin/ANGPTL8 were studied in patients suffering from peritoneal sepsis. Insulin-resistant individuals and subjects without metabolic derangement/systemic inflammation were enrolled as controls. All underwent open abdominal surgery. Circulating betatrophin/ANGPTL8 was analyzed by an enzyme-linked immunosorbent assay and AT mRNA expression levels were assessed by real-time PCR. Standard laboratory analyses including lipid electrophoresis were evaluated. Sepsis patients showed pronounced septic dyslipidemia (p < 0.05 for all major lipid classes). Despite comparable betatrophin/ANGPTL8 mRNA expression in AT (p = 0.24), we found significantly increased circulating betatrophin/ANGPTL8 with septic dyslipidemia (p = 0.009). Expression levels of betatrophin/ANGPTL8 in AT correlated with circulating concentrations in both control groups (r = 0.61; p = 0.008 and r = 0.43; p = 0.034), while this association was undetectable in sepsis. After stratification, betatrophin/ANGPTL8 remained associated with hypertriacylglyceridemia (p < 0.05).

A systematic review and meta-analysis of the hemodynamic effects of etomidate versus other sedatives in patients undergoing rapid sequence intubation

INTRODUCTION

Rapid sequence intubation is an airway rescue and protection technique in which different sedatives are used to perform orotracheal intubation. Etomidate, due to its pharmacokinetic and pharmacodynamic qualities, particularly hemodynamic stability, is the most widely used sedative in this scenario. However, its superiority over other sedatives is controversial.

MATERIALS AND METHODS

We performed a meta-analysis using a pre-designed protocol and PRISMA guidelines to evaluate the mean difference between systolic blood pressure before and after administration of the sedative. We also analyzed the relative risks of hypotension.

RESULTS

Ten studies were included. The incidence of hypotension in patients receiving etomidate ranged from 6.4% to 75.2%, and between 24.0% and 65.9% in patients receiving other sedatives. No significant differences were found in the mean difference in systolic blood pressure during pre-intubation 0.01 mm Hg (95% CI: -0.90; 0.92) or in post-intubation 0.98 mmHg (95% CI: -0.24; 2.20). The relative risk analysis showed that the risk of hypotension is equal to an RR of 1.19 (95% CI: 0.92-1.54) between those who received etomidate and those who received the other sedatives.

CONCLUSIONS

The risk of hypotension after rapid intubation sequence with etomidate does not differ significantly compared to other sedatives. However, the studies included in this review were heterogeneous.

Single-cell atlas of murine adrenal glands reveals immune-adrenal crosstalk during systemic <i>Candida albicans</i> infection

Fungal sepsis remains a major health threat with high mortality, where the adrenal gland stress response has been rarely reported. <i>Candida albicans</i> (<i>C.albicans</i>) is the most common opportunistic fungal pathogen of life-threatening disseminated candidiasis and fungal sepsis. In the present study, we performed single-cell RNA sequencing (scRNA-Seq) using the 10x Genomics platform to analyze the changes in murine adrenal transcriptome following systemic <i>C.albicans</i> infection. A total of 16 021 cells were categorized into 18 transcriptionally distinct clusters, representing adrenocortical cells, endothelial cells, various immune cells, mesenchymal cells, smooth muscle cells, adrenal capsule, chromaffin cells, neurons and glials. As the main cell component in the adrenal gland responsible for steroidogenesis, the adrenocortical cells dramatically diminished and were further grouped into 10 subclusters, which differently distributed in the infected and uninfected samples. Pseudo-time analysis revealed transitions of the adrenocortical cells from the initial normal states to active or dysfunctional states following systemic <i>C.albicans</i> infection <i>via</i> two trajectory paths. Endothelial cells in the highly vascularized organ of adrenal gland further proliferated following infection, with the upregulation of genes positively regulating angiogenesis and downregulation of protective genes of endothelial cells. Immune cells were also excessively infiltrated in adrenal glands of <i>C.albicans</i>-infected mice. Macrophages dominated the immune microenvironments in murine adrenal glands both before and after <i>C.albicans</i> infection, mediating the crosstalk among the steroid-producing cells, endothelial cells and immune cells within the adrenal gland. NLR family, pyrin domain containing 3 (NLRP3, encoded by <i>Nlrp3</i>) and complement receptor 3 (CR3, encoded by <i>Itgam</i>) were found to be significantly upregulated on the adrenal macrophages upon systemic <i>C.albicans</i> infection and might play critical roles in mediating the myeloid response. Meanwhile, the number and strength of the interactions between the infiltrating immune cells and adrenal resident cells were unveiled by cell-cell communication analysis to be dramatically increased after systemic <i>C.albicans</i> infection, indicating that the immune-adrenal crosstalk might contribute to the compromised functions of adrenal cells. Overall, our comprehensive picture of the murine adrenal gland microenvironment in systemic <i>C.albicans</i> infection provides deeper insights into the immune-adrenal cell communications during fungal sepsis.

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

INTRODUCTION

Emergency department (ED) patients undergoing emergent tracheal intubation often have multiple physiologic derangements putting them at risk for post-intubation hypotension. Prior work has shown that post-intubation hypotension is independently associated with increased morbidity and mortality. The choice of induction agent may be associated with post-intubation hypotension. Etomidate and ketamine are two of the most commonly used agents in the ED, however, there is controversy regarding whether either agent is superior in the setting of hemodynamic instability. The goal of this study is to determine whether there is a difference in the rate of post-intubation hypotension who received either ketamine or etomidate for induction. Additionally, we provide a subgroup analysis of patients at pre-existing risk of cardiovascular collapse (identified by pre-intubation shock index (SI) > 0.9) to determine if differences in rates of post-intubation hypotension exist as a function of sedative choice administered during tracheal intubation in these high-risk patients. We hypothesize that there is no difference in the incidence of post-intubation hypotension in patients who receive ketamine versus etomidate.

METHODS

A retrospective cohort study was conducted on a database of 469 patients having undergone emergent intubation with either etomidate or ketamine induction at a large academic health system. Patients were identified by automatic query of the electronic health records from 1/1/2016-6/30/2019. Exclusion criteria were patients <18-years-old, tracheal intubation performed outside of the ED, incomplete peri-intubation vital signs, or cardiac arrest prior to intubation. Patients at high risk for hemodynamic collapse in the post-intubation period were identified by a pre-intubation SI > 0.9. The primary outcome was the incidence of post-intubation hypotension (systolic blood pressure < 90 mmHg or mean arterial pressure < 65 mmHg). Secondary outcomes included post-intubation vasopressor use and mortality. These analyses were performed on the full cohort and an exploratory analysis in patients with SI > 0.9. We also report adjusted odds ratios (aOR) from a multivariable logistic regression model of the entire cohort controlling for plausible confounding variables to determine independent factors associated with post-intubation hypotension.

RESULTS

A total of 358 patients were included (etomidate: 272; ketamine: 86). The mean pre-intubation SI was higher in the group that received ketamine than etomidate, (0.97 vs. 0.83, difference: -0.14 (95%, CI -0.2 to -0.1). The incidence of post-intubation hypotension was greater in the ketamine group prior to SI stratification (difference: -10%, 95% CI -20.9% to -0.1%). Emergency physicians were more likely to use ketamine in patients with SI > 0.9. In our multivariate logistic regression analysis, choice of induction agent was not associated with post-intubation hypotension (aOR 1.45, 95% CI 0.79 to 2.65). We found that pre-intubation shock index was the strongest predictor of post-intubation hypotension.

CONCLUSION

In our cohort of patients undergoing emergent tracheal intubation, ketamine was used more often for patients with an elevated shock index. We did not identify an association between the incidence of post-intubation hypotension and induction agent between ketamine and etomidate. Patients with an elevated shock index were at higher risk of cardiovascular collapse regardless of the choice of ketamine or etomidate.

The preclinical pharmacological study of a novel intravenous anesthetic, ET-26 hydrochloride, in aged rats

Background

ET-26 hydrochloride (ET-26HCl) is a novel analogue of etomidate approved for clinical trials. However, all results from recent studies were accomplished in young adult animals. The objective of this study was to evaluate the efficacy and safety of ET-26HCl in aged rats.

Methods

Aged Sprague-Dawley rats were randomly divided into three groups (three males and three females in each group) were given dose of two-fold of median effective dose (ED₅₀) of ET-26HCl, etomidate and propofol: the measurements of loss of the righting reflex (LORR) and cardiovascular and respiratory function after injection at the two-fold dose of the median effective dose were used for evaluation of effectiveness and safety, and the modified adrenocorticotropic hormone-stimulation experiment was used to evaluate the inhibition effect of the drugs on the synthesis of adrenal cortical hormones.

Results

There was no significant difference in the onset time among propofol, etomidate and ET-26HCl. The duration of propofol (850.5 ± 77.4 s) was significantly longer than that caused by etomidate (489.8 ± 77.0 s, p = 0.007) and ET-26HCl (347.3 ± 49.0 s, p = 0.0004). No significant difference was observed in the time to stand and normal activity among drugs. A total of 66.7% of rats in the ET-26HCl group were evaluated to have mild hematuria. Then, etomidate and ET-26HCl had a milder blood pressure inhibition effect than propofol. Apnea was observed in all rats administered propofol and the duration for this side effect was 45.0 ± 9.0 s. For etomidate and ET-26HCl, no apnea was observed. No other clinical signs of side-effect were observed, and no rats died. No significant difference was observed in corticosterone concentrations between ET-26HCl and solvent group. However, rats administered etomidate had lower corticosterone concentrations than those administered ET-26HCl at 15, 30, and 60 min.

Conclusions

Our results indicate ET-26HCl in aged rats is an effective sedative-hypnotic with stable myocardial and respiratory performance and also have mild adrenocortical suppression. Thus, these findings increase the potential for the clinical use of ET-26HCl in the elderly population.

Non-diabetic euglycaemic ketoacidosis and rapid weight loss in a post-traumatic surgical patient: is the outré preventable?

To highlight the implications of the metabolic stress response and the role of anaesthesia in attenuating its deleterious effects, we present this extremely rare case of non-diabetic euglycaemic ketoacidosis with rapid weight loss in a post-traumatic surgical patient. Ketoacidosis is the accumulation of ketone bodies in blood and is generally associated with relative or absolute insulin deficiency secondary to diabetes mellitus, sodium-glucose cotransporter 2 inhibitors and extensive fasting. The stress of systemic disease, trauma or surgery in such predisposed patients could precipitate ketoacidosis. Our patient developed high anion gap metabolic acidosis intraoperatively due to ketosis, a potentially life-threatening complication, without any predisposing factors as a result of metabolic stress of major trauma and surgery. Aiding the interpretation, he lost 15 kg weight perioperatively, suggesting his body was in a hypercatabolic state. This report emphasises the value of anaesthetic techniques to prevent such rare complications.

Independent risk factors of mortality in patients with sepsis receiving single-dose etomidate as an induction agent during rapid sequence intubation in a large tertiary emergency department in Thailand

BACKGROUND

There is limited evidence regarding factors associated with mortality in septic patients receiving etomidate. This study aimed to determine independent pre-intubation factors predicting 28-day mortality in septic patients receiving single-dose etomidate as an induction agent during rapid sequence intubation (RSI).

METHODS

This single-center retrospective cohort study included intubated septic patients receiving etomidate as an induction agent during RSI in the emergency department of Siriraj hospital, Bangkok, Thailand, between January 1st, 2016 and June 30th, 2020. Pre-intubation characteristics were compared between survivors and non-survivors. Independent risk factors associated with 28-day mortality were identified using the Cox proportional hazards regression model. Association between etomidate dosage and mortality was also determined.

RESULTS

A total of 344 patients, 238 (69%) survivors and 106 (31%) non-survivors, were included in the analyses. The initial Cox hazards model identified a pre-intubation lactate level ≥ 4 mmol/L as an independent factor associated with mortality (adjusted Hazards ratio [aHR] 2.66, 95% confidence interval [CI] 1.55-4.56). After removing lactate level from the model due to limited lactate values in the data, cancer was also predictive of 28-day mortality (aHR 1.83, 95%CI 1.10-3.04), while patients with respiratory infections and underlying chronic lung disease were associated with lower mortality (aHR 0.54, 95%CI 0.37-0.80 and aHR 0.57, 0.33-0.96, respectively). Etomidate dosage was not associated with mortality in our study.

CONCLUSION

In septic patients who received a single dose of etomidate, a pre-intubation lactate level ≥ 4 mmol/L and cancer were associated with increased 28-day mortality, while respiratory infection and underlying chronic lung disease were associated with lower mortality. Physicians may take these factors into consideration when selecting induction agents for septic patients.

E161111 is an ultra-short-acting etomidate analogue with stable haemodynamics that elicits only slight adrenocortical suppression in rats

Purpose

We report on a novel ultra-short-acting etomidate analogue, E161111, which has the same primary metabolite as etomidate.

Methods

The metabolic rate of E161111 was determined in rat plasma and liver homogenate. Rats were infused for 30 or 60 min to maintain light sedation at Richmond Agitation-Sedation Scale (RASS) for -2 to 0 score. Mean arterial pressure (MAP) was monitored during 30 min infusion. The serum corticosterone was determined during and 3 h after infusion as a measure of adrenocortical function.

Results

E161111 was not detected in rat plasma at 1 min (t_1/2 = 6.69 ± 0.07 s) and in rat liver homogenates at 5 min (t_1/2 = 10.20 ± 3.76 s); its main metabolic product was etomidate acid. The recovery time from loss of righting reflex (LORR) was 4.3 ± 1.5 min after 1-h infusion of E161111. During 30 min infusion, E161111 did not cause MAP changes. The stimulated serum corticosterone levels after 1-h infusion of E161111 were significantly higher than that after 1-h infusion of etomidate at all time points tested for the 3 h study.

Conclusions

E161111 was metabolised rapidly, the metabolites were same as etomidate, and the recovery time after 1-h infusion was short. It elicited haemodynamic stability and milder suppression of corticosterone than that elicited by etomidate.

Endotracheal intubation sedation in the intensive care unit

Endotracheal intubation is one of the most common, yet most dangerous procedure performed in the intensive care unit (ICU). Complications of ICU intubations include severe hypotension, hypoxemia, and cardiac arrest. Multiple observational studies have evaluated risk factors associated with these complications. Among the risk factors identified, the choice of sedative agents administered, a modifiable risk factor, has been reported to affect these complications (hypotension). Propofol, etomidate, and ketamine or in combination with benzodiazepines and opioids are commonly used sedative agents administered for endotracheal intubation. Propofol demonstrates rapid onset and offset, however, has drawbacks of profound vasodilation and associated cardiac depression. Etomidate is commonly used in the critically ill population. However, it is known to cause reversible inhibition of 11 β-hydroxylase which suppresses the adrenal production of cortisol for at least 24 h. This added organ impairment with the use of etomidate has been a potential contributing factor for the associated increased morbidity and mortality observed with its use. Ketamine is known to provide analgesia with sedation and has minimal respiratory and cardiovascular effects. However, its use can lead to tachycardia and hypertension which may be deleterious in a patient with heart disease or cause unpleasant hallucinations. Moreover, unlike propofol or etomidate, ketamine requires organ dependent elimination by the liver and kidney which may be problematic in the critically ill. Lately, a combination of ketamine and propofol, “Ketofol”, has been increasingly used as it provides a balancing effect on hemodynamics without any of the side effects known to be associated with the parent drugs. Furthermore, the doses of both drugs are reduced. In situations where a difficult airway is anticipated, awake intubation with the help of a fiberoptic scope or video laryngoscope is considered. Dexmedetomidine is a commonly used sedative agent for these procedures.

Etomidate versus ketamine for emergency endotracheal intubation: a randomized clinical trial

PURPOSE

Etomidate and ketamine are hemodynamically stable induction agents often used to sedate critically ill patients during emergency endotracheal intubation. In 2015, quality improvement data from our hospital suggested a survival benefit at Day 7 from avoidance of etomidate in critically ill patients during emergency intubation. In this clinical trial, we hypothesized that randomization to ketamine instead of etomidate would be associated with Day 7 survival after emergency endotracheal intubation.

METHODS

A prospective, randomized, open-label, parallel assignment, single-center clinical trial performed by an anesthesiology-based Airway Team under emergent circumstances at one high-volume medical center in the United States. 801 critically ill patients requiring emergency intubation were randomly assigned 1:1 by computer-generated, pre-randomized sealed envelopes to receive etomidate (0.2-0.3 mg/kg, n = 400) or ketamine (1-2 mg/kg, n = 401) for sedation prior to intubation. The pre-specified primary endpoint of the trial was Day 7 survival. Secondary endpoints included Day 28 survival.

RESULTS

Of the 801 enrolled patients, 396 were analyzed in the etomidate arm, and 395 in the ketamine arm. Day 7 survival was significantly lower in the etomidate arm than in the ketamine arm (77.3% versus 85.1%, difference - 7.8, 95% confidence interval - 13, - 2.4, p = 0.005). Day 28 survival rates for the two groups were not significantly different (etomidate 64.1%, ketamine 66.8%, difference - 2.7, 95% confidence interval - 9.3, 3.9, p = 0.294).

CONCLUSION

While the primary outcome of Day 7 survival was greater in patients randomized to ketamine, there was no significant difference in survival by Day 28.

Infectious Complications after Etomidate vs. Propofol for Induction of General Anesthesia in Cardiac Surgery-Results of a Retrospective, before-after Study

Background: Etomidate is typically used as an induction agent in cardiac surgery because it has little impact on hemodynamics. It is a known suppressor of adrenocortical function and may increase the risk for post-operative infections, sepsis, and mortality. The aim of this study was to evaluate whether etomidate increases the risk of postoperative sepsis (primary outcome) and infections (secondary outcome) compared to propofol. Methods: This was a retrospective before–after trial (IRB EA1/143/20) performed at a tertiary medical center in Berlin, Germany, between 10/2012 and 01/2015. Patients undergoing cardiac surgery were investigated within two observation intervals, during which etomidate and propofol were the sole induction agents. Results: One-thousand, four-hundred, and sixty-two patients, and 622 matched pairs, after caliper propensity-score matching, were included in the final analysis. Sepsis rates did not differ in the matched cohort (etomidate: 11.5% vs. propofol: 8.2%, p = 0.052). Patients in the etomidate interval were more likely to develop hospital-acquired pneumonia (etomidate: 18.6% vs. propofol: 14.0%, p = 0.031). Conclusion: Our study showed that a single-dose of etomidate is not statistically associated with higher postoperative sepsis rates after cardiac surgery, but is associated with a higher incidence of hospital-acquired pneumonia. However, there is a notable trend towards a higher sepsis rate.

Staying InformED: Top emergency Medicine pharmacotherapy articles of 2020

The year 2020 was not easy for Emergency Medicine (EM) clinicians with the burden of tackling a pandemic. A large focus, rightfully so, was placed on the evolving diagnosis and management of patients with COVID-19 and, as such, the ability of clinicians to remain up to date on key EM pharmacotherapy literature may have been compromised. This article reviews the most important EM pharmacotherapy publications indexed in 2020. A modified Delphi approach was utilized for selected journals to identify the most impactful EM pharmacotherapy studies. A total of fifteen articles, eleven trials and four meta-analyses, were identified. This review provides a summary of each study, along with a commentary on the impact to the EM literature and EM clinician.

Safety Pharmacology Study of ET-26 Hydrochloride, a Potential Drug for Intravenous General Anesthesia, in Rats and Beagle Dogs

Background: ET-26 hydrochloride (ET-26HCl), a class 1 new drug, was developed to reserve the advantages of etomidate with a mild adrenocortical inhibition.

Purpose: this study was to evaluate the potential adverse effects on the cardiovascular system of beagle dogs and the respiratory and central nervous systems of rats.

Methods: three established methods, the whole-body plethysmography for respiratory function, the prototype telemetry transmitter for cardiovascular function, and the standardized functional observational battery for central nervous system function, were accomplished with Good Laboratory Practice standards.

Results: no significant difference in the tidal volume, but the respiratory rate and minute ventilation were reduced. The degree of inhibition was the most serious in the first 15 min after dosing and function fully recovered after 1 h. For male rats, the respiratory rate of male rats was reduced significantly at 15 min after injection with ET-26HCl (4 mg/kg, 28.6%, p ≤ 0.01; 8 mg/kg, 24.5%, p ≤ 0.01; 16 mg/kg, 44.5%, p ≤ 0.001), and the minute ventilation at 15 min was decreased by 20.1% (4 mg/kg, p = 0.034), 22.2% (8 mg/kg, p = 0.019), and 44.6% (16 mg/kg, p ≤ 0.001) as compared to control group. As with male rats, the respiratory rate of the female rats was reduced significantly at 15 min (4 mg/kg, 23.3%, p ≤ 0.01; 8 mg/kg, 29.2%, p ≤ 0.001; 16 mg/kg, 44.1%, p ≤ 0.001), and the minute ventilation was decreased by 25.2% (4 mg/kg, p ≤ 0.001), 23.0% (8 mg/kg, p ≤ 0.01), and 47.6% (16 mg/kg, p ≤ 0.001). Then, all the variations in cardiovascular functions were within the expected range for normal biological variation, we concluded that ET-26HCl, even at 10-fold ED₅₀, still does not exert toxicological effects on the cardiovascular system. For male beagle dogs, the systolic blood pressure after 24 h following administration of vehicle control or 8, 12, or 16 mg/kg ET-26HCl was 137.80 ± 5.55, 131.76 ± 10.03, 139.88 ± 8.35, and 141.28 ± 8.75 mmHg, respectively. The diastolic blood pressure was 71.16 ± 4.84, 66.52 ± 8.50, 73.64 ± 8.51, and 74.24 ± 8.68 mmHg, respectively. For female beagle dogs, the systolic blood pressure after 24 h following administration of vehicle control or 8, 12, or 16 mg/kg ET-26HCl was 128.28 ± 5.22, 124.76 ± 7.29, 134.88 ± 5.56, and 135.36 ± 8.72 mmHg, respectively. The diastolic blood pressure was 67.00 ± 4.10, 62.12 ± 7.87, 69.44 ± 6.40, and 70.20 ± 8.42 mmHg, respectively. In central nervous system function experiment, all the changes observed in the functional observational battery tests, including motor activity, behavior, coordination, and sensory and motor reflex responses, and reduced body temperature, were resulted in general anesthesia effect of ET-26HCl.

Conclusion: ET-26HCl exerts mild, reversible effects on respiratory, cardiovascular, and central nervous system function as verified by standard in vivo animal models.

Propofol, Ketamine, and Etomidate as Induction Agents for Intubation and Outcomes in Critically Ill Patients: A Retrospective Cohort Study

Propofol, ketamine, and etomidate are common anesthetic agents for induction of anesthesia in the ICU. The choice between these agents is complex and may not depend solely upon severity of illness.

OBJECTIVES

To evaluate the association between the administration of propofol, ketamine, and etomidate and ICU, hospital mortality, and length of stay.

DESIGN SETTING AND PARTICIPANTS

Retrospective single-center cohort study. ICUs in a tertiary medical center, between January 01, 2012, and December 31, 2017. Critically ill adult patients given a single IV anesthetic for intubation.

MAIN OUTCOME AND MEASURES

Primary outcomes were ICU and hospital mortality. Secondary outcomes were ICU- and hospital-free days through 28 days. An inverse probability of treatment weighed approach was used. The propensity score was estimated using a generalized logit model as a function of patient characteristics, admission source, ICU type, readmission status, length of ICU stays prior to intubation, and acute physiology score. Mortality outcomes were assessed with weighted logistic regression and -free days assessed by weighted linear regression with Bonferroni correction for pairwise comparisons.

RESULTS

Of 2,673 patients, 36% received propofol, 30% ketamine and 34% etomidate. Overall ICU and hospital mortality were 19% and 29%, respectively. Patients given ketamine had higher odds of ICU mortality (1.45; [95% CI, 1.07-1.94]; p = 0.015) and patients given etomidate had higher odds of ICU mortality (1.87; 1.40-2.49; p < 0.001), hospital mortality (1.43; 1.09-1.86; p = 0.009), and less ICU-free days (-2.10; -3.21 to -1.00; p < 0.001) than those given propofol. Patients given ketamine and etomidate had similar odds of hospital mortality (1.06; 0.80-1.42; p = 0.761) and similar hospital-free days (0.30; -0.81 to 1.40; p = 0.600).

CONCLUSIONS AND RELEVANCE

Compared with ketamine and etomidate, propofol was associated with better outcome in critically ill patients undergoing anesthesia for intubation. Even after adjusting for severity of illness prior to intubation, residual confounders cannot be excluded.

Anesthesia Considerations in Neurological Emergencies

Airway obstruction and respiratory failure are common complications of neurological emergencies. Anesthesia is often employed for airway management, surgical and endovascular interventions or in the intensive care units in patients with altered mental status or those requiring burst suppression. This article provides a summary of the unique airway management and anesthesia considerations and controversies for neurologic emergencies in general, as well as for specific commonly encountered conditions: elevated intracranial pressure, neuromuscular respiratory failure, acute ischemic stroke, and acute cervical spinal cord injury.

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.

Evaluation and Management of the Physiologically Difficult Airway: Consensus Recommendations From Society for Airway Management

Multiple international airway societies have created guidelines for the management of the difficult airway. In critically ill patients, there are physiologic derangements beyond inadequate airway protection or hypoxemia. These risk factors contribute to the "physiologically difficult airway" and are associated with complications including cardiac arrest and death. Importantly, they are largely absent from international guidelines. Thus, we created management recommendations for the physiologically difficult airway to provide practical guidance for intubation in the critically ill. Through multiple rounds of in-person and telephone conferences, a multidisciplinary working group of 12 airway specialists (Society for Airway Management's Special Projects Committee) over a time period of 3 years (2016-2019) reviewed airway physiology topics in a modified Delphi fashion. Consensus agreement with the following recommendations among working group members was generally high with 80% of statements showing agreement within a 10% range on a sliding scale from 0% to 100%. We limited the scope of this analysis to reflect the resources and systems of care available to out-of-operating room adult airway providers. These recommendations reflect the practical application of physiologic principles to airway management available during the analysis time period.

A Critical Appraisal of the Effects of Anesthetics on Immune-system Modulation in Critically Ill Patients With COVID-19

Purpose

The aim of the present article was to briefly summarize current knowledge about the immunomodulatory effects of general anesthetics and the possible clinical effects of this immunomodulation in patients with COVID-19.

Methods

The PubMed, Scopus, and Google Scholar databases were comprehensively searched for relevant studies.

Findings

The novel coronavirus causes a wide spectrum of clinical manifestations, with a large absolute number of patients experiencing severe pneumonia and rapid progression to acute respiratory distress syndrome and multiple organ failure. In these patients, the equilibrium of the inflammatory response is a major determinant of survival. The impact of anesthetics on immune-system modulation may vary and includes both pro-inflammatory and anti-inflammatory effects.

Implications

Inhibition of the development of severe inflammation and/or the enhancement of inflammation resolution by anesthetics may limit organ damage and improve outcomes in patients with COVID-19.

Discovery of the EL-0052 as a potential anesthetic drug

As a γ-aminobutyric acid A receptor (GABA_AR) inhibitor, etomidate fulfills several characteristics of an ideal anesthetic agent, such as rapid onset with rapid clearance and high potency, along with cardiovascular stability. Unfortunately, etomidate has been reported to inhibit CYP11B1 at hypnotic doses, which is associated with a marked increase in patient deaths due to this unexpected off-target effect. In this study, molecular docking was used to simulate the binding mode of etomidate with GABA_AR and CYP11B1. Based on the in-depth analysis of the binding mode, strong electron-withdrawing group on the C4 position of the imidazole ring was introduced to reduce the charge density of the nitrogen, which is beneficial in reducing the coordination bond between the imidazole nitrogen and heme iron in CYP11B1, as well as in reducing the adrenocortical suppression. Based on the results of ADMET property prediction, MEP analysis, and molecular docking simulation, 4-fluoroetomidate (EL-0052) was designed and synthesized. In vivo studies in rats and mice confirmed that EL-0052 had the efficacy similar to etomidate, but without adrenocortical suppression. These findings suggested that EL-0052 was superior to etomidate and support the continued development of EL-0052 as a preclinical candidate as an anesthetic.

Anesthetic Induction With Etomidate in Cardiac Surgical Patients: A PRISMA-Compliant Systematic Review and Meta-Analysis

OBJECTIVE

This meta-analysis aimed to systematically review the effects of etomidate (ETM) during anesthetic induction on patients undergoing cardiac surgery.

DESIGN

Systematic review and meta-analysis.

SETTING

Operating room.

PARTICIPANTS

Patients undergoing cardiac surgery.

INTERVENTIONS

ETM or control drugs.

MEASUREMENTS AND MAIN RESULTS

PubMed, Cochrane Library, OVID, and EMBASE were searched through August 31, 2020. Primary outcomes included hemodynamic profiles and stress responses. Secondary outcomes included morbidity, mortality, and postoperative recovery. For continuous/dichotomous variables, treatment effects were calculated as weighted mean difference (WMD)/odds ratio (OR) and 95% confidence interval (CI). A database search yielded 18 randomized controlled trials including 1,241 patients. The present meta-analysis demonstrated that ETM-anesthetized patients had lower heart rates (WMD, -3.31; 95% CI -5.43 to -1.19; p = 0.002), higher blood pressures (systolic blood pressure: WMD, 12.02; 95% CI 6.24 to 17.80; p < 0.0001; diastolic blood pressure: WMD, 5.23; 95% CI 2.39 to 8.08; p = 0.0003; mean arterial pressure (MAP): WMD, 8.64; 95% CI 5.85 to 11.43; p < 0.00001), less requirement for vasopressor (OR, 0.26; 95% CI 0.15 to 0.44; p < 0.00001), and more nitroglycerin usage (OR, 14.89; 95% CI 4.92 to 45.08; p < 0.00001) during anesthetic induction. Current meta-analysis also demonstrated that single-dose ETM lowered cortisol levels transiently and did not have a significant effect on endogenous norepinephrine and epinephrine levels and was not associated with increased postoperative inotrope and/or vasopressor requirement. Additionally, the meta-analysis suggested that ETM anesthesia was associated with neither increased mortality nor morbidity, except a higher incidence of transient adrenal insufficiency in ETM recipients.

CONCLUSION

The present meta-analysis suggested that single-dose ETM during anesthetic induction could be associated with more stable hemodynamics, transient and reversible lower cortisol levels, and a higher adrenal insufficiency incidence, but not worse outcomes in cardiac surgical patients.

Effects of etomidate use in ICU patients on ventilator therapy: a study of 12,526 patients in an open database from a single center

Background

There is a debate regarding the safety of etomidate. We evaluated the effects of etomidate on mortality in a large cohort of critical care patients.

Methods

This retrospective matched-cohort study was performed using the Medical Information Mart for Intensive Care version 3 (MIMIC-III) database. Among 12,526 adult patients who were prescribed etomidate or propofol on the first day of mechanical ventilation, 625 patients administered etomidate were statistically matched with 6,250 patients administered propofol. The primary outcome measures were all-cause in-hospital mortality, 48-hour survival, cardiovascular morbidity, and infectious morbidity. Logistic regression analysis with stepwise selection of variables was performed to examine the dose–mortality relationship of etomidate.

Results

All-cause in-hospital mortality was 1.84 times higher in the etomidate cohort (OR: 1.84, 98.75% CI: 1.42, 2.37). Compared to the propofol cohort, the etomidate cohort showed 57% lower odds of 48-hour survival (0.43 [0.27, 0.73]), no difference in odds of cardiovascular morbidity (0.86 [0.66, 1.12]), and 1.77 times higher odds of infectious morbidity (1.77 [1.35, 2.31]). Additionally, the odds of mortality increased by 1.36 times per 0.1 mg/kg of etomidate (1.36 [95% CI: 1.23, 1.49]).

Conclusions

Etomidate is a poor choice as a hypnotic drug on the first day of mechanical ventilation, as it is associated with a dose-dependent increase in all-cause mortality, and does not improve survival for the first 48 h.

Etomidate Use Is Associated With Less Hypotension Than Ketamine for Emergency Department Sepsis Intubations: A NEAR Cohort Study

OBJECTIVE

The objectives of this study were 1) to describe the current use of etomidate and other induction agents in patients with sepsis and 2) to compare adverse events between etomidate and ketamine in sepsis.

METHODS

This was an observational cohort study of the prospective National Emergency Airway Registry (NEAR) data set. Descriptive statistics were used to report the distribution of induction agents used in patients with sepsis. Adverse events were compared using bivariate analysis, and a sensitivity analysis was conducted using a propensity score-adjusted analysis of etomidate versus ketamine.

RESULTS

A total of 531 patients were intubated for sepsis, and the majority (71%) were intubated with etomidate as the initial induction agent. Etomidate was less frequently used in sepsis patients than nonsepsis patients (71% vs. 85%, odds ratio [OR] = 0.4, 95% confidence interval [CI] = 0.4 to 0.5). Sepsis patients had a greater risk of adverse events, and vasopressor therapy was required for 25% of patients after intubation. Postprocedure hypotension was higher between those intubated for sepsis with ketamine versus etomidate (74% vs. 50%, OR = 2.9, 95% CI = 1.9 to 4.5). After confounding by indication in the propensity score-adjusted analysis was accounted for, ketamine was associated with more postprocedure hypotension (OR = 2.7, 95% CI = 1.1 to 6.7). No difference in emergency department deaths was observed.

CONCLUSIONS

Etomidate is used less frequently in sepsis patients than nonsepsis patients, with ketamine being the most frequently used alternative. Ketamine was associated with more postprocedural hypotension than etomidate. Future clinical trials are needed to determine the optimal induction agent in patients with sepsis.

A Comparison of Etomidate, Ketamine, and Methohexital in Emergency Department Rapid Sequence Intubation

BACKGROUND

Rapid sequence intubation (RSI) is routinely used for emergent airway management in the emergency department (ED). It involves the use of induction, and paralytic agents help facilitate endotracheal tube placement.

OBJECTIVE

In response to a previous national drug shortage resulting in the use of alternative induction agents for RSI, we describe the effectiveness and safety of ED RSI with ketamine or methohexital compared with etomidate.

METHODS

We conducted a retrospective, single-center observational study from March 1-August 31, 2012 describing RSI with etomidate, ketamine, and methohexital. All adult patients undergoing RSI in the ED who received etomidate prior to its shortage and methohexital or ketamine during the shortage were included.

RESULTS

The study included 47, 9, and 26 patients in the etomidate, ketamine, and methohexital groups, respectively. Successful intubation on the first attempt occurred in 74.5%, 55.6%, and 73.1% of the etomidate, ketamine, and methohexital groups, respectively. The mean number of intubation attempts and time to intubation seemed to be similar in all groups. At least three intubation attempts were required in 22.2% and 7.7% of the ketamine and methohexital groups, respectively, compared with none in the etomidate group. Two aspirations were observed in the etomidate group.

CONCLUSION

Methohexital and etomidate had similar rates of successful intubation on the first attempt and seem to be more effective than ketamine. Etomidate may reduce the need for three or more intubation attempts. Larger, prospective studies are needed to determine if ketamine or methohexital are more effective than etomidate for RSI.

Etomidate, Adrenal Insufficiency and Mortality Associated With Severity of Illness: A Meta-Analysis

PURPOSE

Etomidate causes adrenal insufficiency. Yet in critically ill patients, it is controversial whether it increases mortality rates above that of comparator anesthetic induction agents. We postulated that etomidate would increase relative mortality rates correspondingly to the severity of illness as defined by SAPS or APACHE scores.

MATERIALS AND METHODS

A literature search was performed on Pub Med, SCOPUS, and Cochrane Reviews for human studies, regardless of language, between 1983 and February 2020. The search strategy used keywords, "etomidate," "adrenal insufficiency," "glucocorticoid," and "intensive care." Both authors reviewed electronic data search titles, abstracts and extracted data, which were checked by the other reviewer. Primary outcome was 28-day survival. Secondary outcome was adrenal insufficiency.

RESULTS

There were 29 trials of etomidate versus comparators in 8584 patients. Etomidate was associated with adrenal insufficiency (risk ratio (rr) = 1·54, 95% CI; 1·42, 1·67, p < 0.001) and increased overall relative mortality rates (rr = 1.09, CI;1.04,1.16, p = 0.001). Meta-regression showed that with etomidate there was a continuous progressive relative risk of mortality associated with increasing severity of illness (predefined in each article by standard critical illness scores). In those patients who had a predicted mortality rate > the median for this analysis (predicted mortality 44%) the relative mortality rate (rr) = 1.20, Ci;1.12,1.29, p < 0.001, the absolute risk difference (rd) = 0.08, CI;0.05,0.11, p < 0.0001 and the number needed to harm (1/rd) was 12.5. In those with a calculated predicted mortality <44% there was no increase in relative mortality rate.

CONCLUSIONS

Whereas etomidate causes adrenal insufficiency, it was not shown to increase mortality in many analyzed here in ICU settings. However, etomidate associated relative mortality rates increased progressively and correlated with the severity of critical illness scores. Intensivists should anticipate the need for glucocorticoid supplementation after etomidate in those with severe critical illness and in those with acute deterioration of vital signs.

Pericardial Effusions in Patients With Cancer: Anesthetic Management and Survival Outcomes

OBJECTIVES

The objective of this study was to describe practice patterns of anesthetic management during pericardial window creation.

DESIGN

Retrospective observational cohort study.

SETTING

Single tertiary cancer center.

PARTICIPANTS

A total of 150 patients treated for cancer between 2011 and 2015 were included in the study.

MEASUREMENTS AND MAIN RESULTS

The primary objective was to evaluate anesthetic management in pericardial window creation. Secondary outcomes were 30-day mortality and overall survival after pericardial window creation. Thirty-day mortality was 19.3%, and median survival was 5.84 months. Higher American Society of Anesthesiologists (ASA) physical status of patients was associated with preinduction arterial line placement (51% ASA 3 v 79% ASA 4; p = 0.002) and use of etomidate for anesthetic induction (34% ASA 3 v 60% ASA 4; p = 0.003). However, there was no association between anesthetic management and presence of tamponade in these patients. Cardiac aspirate volume (per 10 mL: odds ratio [OR], 1.02 [95% CI, 1.0-1.04]; p = 0.026) and intraoperative arrhythmia (atrial fibrillation: OR, 6.76 [95% CI, 1.2-37.49]; p = 0.029; sinus tachycardia: OR, 4.59 [95% CI, 1.25-16.90]; p = 0.022) were associated independently with increased 30-day mortality. High initial heart rate (per 10 beats per minute: hazard ratio [HR], 1.18 [95% CI, 1.05-1.33]; p = 0.005) in the operating room and intraoperative sinus tachycardia (HR, 1.86 [95% CI, 1.15-3.03]; p = 0.012) were associated independently with worse overall survival.

CONCLUSION

Risk of death after pericardial window creation remains high in patients with cancer. Variations in anesthetic management did not affect survival in oncologic patients with pericardial effusions.

Use of etomidate in patients with heart failure undergoing noncardiac surgery

BACKGROUND

Patients with symptomatic and asymptomatic heart failure undergoing noncardiac surgery may benefit from the haemodynamic profile of etomidate. However, the safety of etomidate in this population is unknown. We examined anaesthesiologist variation in etomidate use and assessed its safety using an instrumental variable approach to account for differences in treatment selection.

METHODS

A retrospective cohort study of 19 714 patients with heart failure undergoing noncardiac surgery at two tertiary care institutions from January 2006 to December 2017 was performed. The proportion of etomidate use among 294 anaesthesiologists was examined and adjusted risk differences (aRD) for in-hospital and 30-day mortality were calculated using physician preference for etomidate as an instrumental variable.

RESULTS

Etomidate was used in 14.3% (2821/19 714) of patients. Preference for etomidate varied substantially among individual anaesthesiologists with the lowest and highest quartile users using etomidate in 0-4.7% and 20.4-66.7% of their own heart failure patients, respectively. The adjusted instrumental variable analysis showed no significant differences in the risk of in-hospital (aRD -0.2%; 95% confidence interval, -2.4%-1.9%; P=0.83) or 30 day mortality (aRD 0.2%; 95% confidence interval, -2.5%-2.9%; P=0.90). Anaesthesiologists with higher preferences for etomidate were more experienced (greater heart failure and total case volume) than anaesthesiologists with lower preferences for etomidate.

CONCLUSIONS

We found substantial variability in anaesthesiologists' preference for etomidate for use in patients with heart failure undergoing noncardiac surgery. There was no association between etomidate use and in-hospital or 30-day mortality. Etomidate is not inferior to other currently used options for induction of general anaesthesia in patients with heart failure.

Preclinical Pharmacokinetics Study of a Novel Intravenous Anesthetic ET-26 Hydrochloride

BACKGROUND

ET-26 hydrochloride is a novel intravenous anesthetic, approved for clinical trials, that produces a desirable sedative-hypnotic effect with stable myocardial performance and mild adrenocortical suppression in rats and beagle dogs. The objective of this study was to assess the absorption, distribution, metabolism, and excretion of ET-26 hydrochloride.

METHODS

Hepatocytes from human, monkey, dog, rat, and mouse were used to determine the metabolites of ET-26 hydrochloride. Distribution and excretion were assessed in rats and pharmacokinetic studies were performed in beagle dogs.

RESULTS

The metabolic pathway and proposed structure of metabolites were fully assessed resulting from the biotransformation reactions of hydrolysis, dehydrogenation, demethylation and glucuronic acid conjugation. The main distribution of the drug was in fat (15067 ± 801 ng/ml) and liver (13647 ± 1126 ng/ml), and the kidney was the primary excretion route (4.47%-11.94%). The Cmax after injection with 1.045 mg/kg, 2.09 mg/kg, and 4.18 mg/kg was 1476.5 ± 138.9 ng/ml, 2846.1 ± 223.3 ng/ml, and 6233.3 ± 238.9 ng/ml, respectively. The t1/2 of the drug was similar across dose groups at 74.8 ± 10.8 min to 81.4 ± 4.2 min. The AUC0-t values were 30208.1 ± 2026.5 min*ng/ml, 62712.8 ± 1808.3 min*ng/ml, and 130465.2 ± 7457.4 min*ng/ml, respectively.

CONCLUSION

The metabolic pathway and the proposed structure of metabolites for ET-26 hydrochloride were fully assessed. The majority of distribution for ET-26 hydrochloride occurs in the fat and liver, while the primary route of excretion for ET-26 hydrochloride is through the kidney. In dogs, pharmacokinetic features of ET-26 hydrochloride had a linear relationship with dosage.

Soft drugs in anesthesia: remifentanil as prototype to modern anesthetic drug development

PURPOSE OF REVIEW

The unique demands of modern anesthesia practice require that medications be effective, well tolerated, and efficient. These attributes are increasingly achieved with the soft drug approach, wherein novel active compounds are specifically designed to be susceptible to rapid biotransformation to inactive metabolites. The present review summarizes the historical background and recent trends in soft drug development in anesthesiology.

RECENT FINDINGS

Soft drug development programs for propranadid, etomidate, and benzodiazepine analogues have been undertaken in recent years. Although all three drugs advanced into human trials, neuro-excitatory adverse effects hampered the propranadid and etomidate analogue projects. Remimazolam, the soft benzodiazepine analogue, is at an advanced stage of development, having already received regulatory approval or review in several countries.

SUMMARY

With succinylcholine as the historical forerunner and remifentanil as the modern prototype, the soft drug paradigm continues to hold promise for the future of anesthesia drug development.

Anaesthetic Considerations for Rationalizing Drug Use in the Operating Theatre: Strategies in a Singapore Hospital During COVID-19

COVID-19 patients in the critical care unit tend to have prolonged hospital stay requiring high doses of sedation and paralysis to treat acute respiratory distress syndrome, resulting in a shortage of these drugs. In our hospital, we have instituted strategies to rationalise drug and oxygen usage. This includes prioritising time-sensitive elective cases, reducing overall elective case load, favouring opioid-reduction strategies and usage of alternative anaesthetic agents not commonly used in ICU. Both intensive care physicians and anaesthesiologists have to cooperate on drug conservation as similar drugs are used in elective operating lists as in the ICU. Patient safety is of utmost importance and we should keep in mind some pitfalls and ethical concerns of these alternative strategies.

Metabolite identification, tissue distribution, excretion and preclinical pharmacokinetic studies of ET-26-HCl, a new analogue of etomidate

ET-26-HCl, a novel anaesthetic agent with promising pharmacological properties, lacks extensive studies on pharmacokinetics and disposition in vitro and in vivo. In this study, we investigated the metabolic stability, metabolite production and plasma protein binding (PPB) of ET-26-HCl along with its tissue distribution, excretion and pharmacokinetics in animals after intravenous administration. Ultra-high performance liquid chromatography–tandem quadrupole time-of-flight mass spectrometry identified a total of eight new metabolites after ET-26-HCl biotransformation in liver microsomes from different species. A hypothetical cytochrome P450-metabolic pathway including dehydrogenation, hydroxylation and demethylation was proposed. The PPB rate was highest in mouse and lowest in human. After intravenous administration, ET-26-HCl distributed rapidly to all tissues in rats and beagle dogs, with the highest concentrations in fat and liver. High concentrations of ET-26-acid, a major hydroxylation metabolite of ET-26-HCl, were found in liver, plasma and kidney. Almost complete clearance of ET-26-HCl from plasma occurred within 4 h after administration. Only a small fraction of the parent compound and its acid form were excreted via the urine and faeces. Taken together, the results added to a better understanding of the metabolic and pharmacokinetic properties of ET-26-HCl, which may contribute to the further development of this drug.

Perioperative Management of Patients with Sepsis and Septic Shock, Part I: Systematic Approach

Sepsis and septic shock are medical emergencies, with high associated mortality. The Surviving Sepsis Campaign has developed definitions and management guidelines, emphasizing the use of hour-1 care bundle. Anesthesiologists frequently encounter sepsis when source control is required. The authors summarize expected manifestations of organ dysfunction and state-of-the-art management of patients with sepsis and septic shock. They highlight an increasingly vital role point-of-care ultrasound examination in the recognition and management of hemodynamic derangements in this patient population. Supporting the role of anesthesiologists as perioperative physicians, the authors provide a framework for transitions of care between operating room and intensive care units.

Preclinical safety evaluation of ET-26 hydrochloride, a novel intravenous anesthetic agent, in beagle dogs

ET-26 hydrochloride (ET-26HCl) is a novel etomidate analogue, approved for clinical trials, which has an effective sedative-hypnotic effect, a stable myocardial performance, and milder adrenocortical suppression than etomidate in rats and beagle dogs. Additionally, ET-26HCl showed similar hemodynamic stability as etomidate in the rat uncontrolled hemorrhagic shock model. Furthermore, ET-26HCl, in the rat lipopolysaccharide-induced sepsis model, was found to have a higher survival rate, a lower inflammatory reaction, and less organ injury. In the present study, we measured the potential adverse effects of ET-26HCl in beagle dogs in accordance with the Guidance on single- and repeated-dose toxicity published by the China Food and Drug Administration. In toxicity studies, single and repeated (14 days) intravenous doses of up to 16 mg/kg were well tolerated, with only pharmacologically related clinical signs seen in both studies. Thus, the no-observed-adverse-effect level (NOAEL) of ET-26HCl was found at 16 mg/kg/day. Toxicokinetic examination demonstrated that ET-26HCl showed a dose-dependent increase to exposure, no gender difference, and no evidence of accumulation. These results provide useful information for guiding a phase I clinical trial of ET-26HCl in healthy volunteers.