Anesthetic induction with etomidate, rather than propofol, is associated with increased 30-day mortality and cardiovascular morbidity after noncardiac surgery

Why sedative hypnotics often fail in development

PURPOSE OF REVIEW

Drug development to support anaesthesia and sedation has been slow with few candidates emerging from preclinical discovery and limited innovation beyond attempted reformulation of existing compounds.

RECENT FINDINGS

The market is well supported by low-cost generic products and development compounds have not been shown to improve patient outcomes or possess other distinctive characteristics to justify the cost of development.

SUMMARY

To make progress in a large-volume, low margin and highly competitive environment requires meaningful advances in relevant basic science. Opportunities exist, but probably require bolder initiatives than further attempts at reformulation or fiddling with the structure of propofol. Extending development ambitions to include nonanaesthesiologist providers challenges professional boundaries but may facilitate cost-effective changes in patterns of care.

A case of fatal poisoning caused by etomidate: evidence from pathological and toxicological analyses

Etomidate is a nonbarbiturate sedative derived from imidazole. Prolonged and excessive use of etomidate can lead to the suppression of adrenocortical function, myoclonus, and even death. This report describes a rare case of a 47-year-old man who died from acute intoxication after oral ingestion of liquid containing etomidate. The cause of death was conclusively attributed to etomidate based on a comprehensive investigation, including autopsy, histopathological examination, toxicological analysis, and biochemical analysis. This is the first reported case of a fatality solely resulting from the oral ingestion of etomidate, which can provide valuable insights for future forensic investigations involving etomidate poisoning. Therefore, it is imperative to share this case with the scientific community.

The need to monitor emerging issues in etomidate usage: the misuse or abuse potential

Since 2011, the misuse or abuse of etomidate has gradually increased when propofol was designated a controlled drug under the Narcotics Control Act in Korea. Accordingly, the Ministry of Food and Drug Safety announced that etomidate would be under the 'Regulation on the designation of drugs that may cause concerns of misuse or abuse' rule in June 2020, which is less stringent than the Narcotics Control Act. Therefore, this review investigates potential misuse or abuse cases of etomidate to consider strengthening its management. A literature search was conducted to compare etomidate with other sedatives in their efficacy and side effects, as well as identify the adverse health outcomes, abuse cases, and analytical methods of etomidate. Etomidate has an equal or higher sedative efficacy and lower risk of adverse cardiopulmonary events than propofol. However, major adverse effects of etomidate include adrenocortical suppression and unproven associated deaths, as well as myoclonus requiring pre-treatment. Although the issue of abuse and misuse of etomidate is emerging in recent years, there are few academic reports on these issues and analytical methods in the forensic field. In order to effectively manage the misuse or abuse of etomidate, it is necessary to continuously monitor related cases with great interest and to be more intensively studied on its abuse potential.

Remimazolam vs Etomidate: Haemodynamic Effects in Hypertensive Elderly Patients Undergoing Non-Cardiac Surgery

Background

Remimazolam tosilate (RT) is a novel ultrashort-acting γ-aminobutyric acid subtype A (GABAA) agonist, with several advantages including rapid induction and recovery, stable haemodynamics, and mild respiratory inhibition. However, studies have not been conducted to explore the haemodynamic effects of RT in elderly hypertensive subjects undergoing non-cardiac surgery. Therefore, we sought to compare the effects of anaesthesia induction using different doses of RT and etomidate on the haemodynamics of this group of patients.

Methods

Patients were recruited into this single-center, prospective, randomized, double-blind trial from October 2022 to June 2023. A total of 150 hypertensive elderly undergoing non-cardiac surgery were randomly assigned into 0.2 mg/kg RT group (Group RL), 0.3 mg/kg RT group (Group RH) and 0.3 mg/kg etomidate group (Group E). The primary outcome of the study was haemodynamic changes (mean arterial pressure fluctuation value -∆MAP and heart rate fluctuation value -∆HR) observed during anaesthesia induction. Secondary outcomes included incidence of adverse cardiovascular events and adverse drug reactions (injection pain and myoclonus), cumulative doses of vasoactive drugs and vital signs at different time points.

Results

Patients in Group E and Group RL had significantly lower haemodynamic fluctuations (∆MAP), lower incidence of hypotension and cumulative dose of ephedrine than subjects in Group RH. Patients in groups RL and RH had significantly lower incidence of injection pain and myoclonus compared with patients in group E. The results showed no statistically significant differences in ∆HR, hypertension, bradycardia, tachycardia, and time to loss of eye-opening reflex and start of intubation, and vital signs at different time points among the three groups.

Conclusion

Use of low-dose RT (0.2 mg/kg) for induction of non-cardiac surgical anaesthesia in elderly hypertensive patients is more effective in maintaining haemodynamic stability and has fewer adverse effects compared with etomidate.

General Anesthesia Versus Nongeneral Anesthesia for Patients With Acute Posterior Circulation Stroke Undergoing Endovascular Therapy: A Systematic Review and Meta-analysis

There is continued controversy regarding the optimal anesthetic technique for endovascular therapy in patients with acute posterior circulation ischemic stroke. To compare the clinical outcomes general anesthesia (GA) and non-GA, we performed a systematic review and meta-analysis of randomized controlled trials and observational studies focused on the anesthetic management for endovascular therapy in patients with acute posterior circulation stroke, without language restriction. In addition, we compared clinical outcomes among the studies with different non-GA types (conscious sedation or local anesthesia). Outcome variables were functional independence, excellent outcomes, favorable outcomes, mortality, successful recanalization, hemodynamic instability, intracerebral hemorrhage, and respiratory or vascular complications. Eight studies including 1777 patients were identified. Although GA was associated with a lower odds of functional independence at 90 days (odds ratio [OR]: 0.55; 95% confidence interval [CI] 0.38 to 0.81; P =0.009), substantial heterogeneity was noted ( I2 =65%). Subgroup analysis showed that GA was associated with higher odds of mortality than conscious sedation (OR: 1.83; 95% CI, 1.30 to 2.57; I2 =0%), but there was no difference between GA and local anesthesia ( I2 =0%). Interestingly, subgroup analysis did not identify a relationship between functional independence and GA compared with local anesthesia (OR: 0.90; 95% CI, 0.64 to 1.25; P =0.919; I2 =0%). This meta-analysis demonstrates that GA is associated with worse outcomes in patients with acute posterior circulation stroke undergoing endovascular therapy based on current studies.

Development and usage of an anesthesia data warehouse: lessons learnt from a 10-year project

This paper describes the development and implementation of an anesthesia data warehouse in the Lille University Hospital. We share the lessons learned from a ten-year project and provide guidance for the implementation of such a project. Our clinical data warehouse is mainly fed with data collected by the anesthesia information management system and hospital discharge reports. The data warehouse stores historical and accurate data with an accuracy level of the day for administrative data, and of the second for monitoring data. Datamarts complete the architecture and provide secondary computed data and indicators, in order to execute queries faster and easily. Between 2010 and 2021, 636 784 anesthesia records were integrated for 353 152 patients. We reported the main concerns and barriers during the development of this project and we provided 8 tips to handle them. We have implemented our data warehouse into the OMOP common data model as a complementary downstream data model. The next step of the project will be to disseminate the use of the OMOP data model for anesthesia and critical care, and drive the trend towards federated learning to enhance collaborations and multicenter studies.

Comparison of Remimazolam Tosilate and Etomidate on Hemodynamics in Cardiac Surgery: A Randomised Controlled Trial

Background

Remimazolam tosilate (RT) is a new ultrashort-acting γ-aminobutyric acid subtype A (GABA_A) agonist, with the characteristics of rapid onset and offset, minimal cardiorespiratory depression. Currently, few studies have compared the effect of RT and etomidate on hemodynamics during anesthesia induction. Here, we aimed to compare the hemodynamic effects of different doses of RT and etomidate for anesthesia induction in patients undergoing cardiac surgeries.

Methods

Patients were recruited from January to September 2022 in this single-center, prospective, randomized, double-blind trial. A total of 117 patients undergoing selective valve replacement surgery were randomly divided into low-dose RT (0.2 mg/kg) group (group LR), high-dose RT (0.3 mg/kg) group (group HR), or etomidate (1.5 mg/kg) group (group E), respectively. The primary outcome was hemodynamic fluctuations (mean arterial pressure fluctuation value [∆MAP]; heart rate fluctuation value [∆HR]) during anesthesia induction. Secondary outcomes included the incidence of adverse drug reactions (injection pain and myoclonus) and adverse cardiovascular events, vital signs at different time points and the cumulative doses of vasoactive drugs.

Results

The hemodynamic fluctuations (∆MAP) in group LR and group E were significantly lower than that in group HR. In addition, the incidence of hypotension and the cumulative norepinephrine doses in group E and group LR were also significantly lower than that in group HR. Furthermore, the incidence of injection pain and myoclonus in group LR and group HR were less frequently recorded compared with group E. There were no significant differences in terms of ∆HR, tachycardia, hypertension, severe bradycardia, vital signs at different time points, lactic acid and blood glucose between both groups.

Conclusion

Compared with etomidate, low-dose RT (0.2mg/kg) can not only provide stable hemodynamic parameters but also cause fewer adverse reactions when used for anesthesia induction in patients with cardiac disease.

Effect of remimazolam tosilate versus etomidate on hemodynamics in patients undergoing valve replacement surgery: study protocol for a randomized controlled trial

BACKGROUND

Patients with a history of cardiac disease are prone to develop cardiovascular adverse events such as hypotension, hypertension, and tachycardia during anesthesia induction. Therefore, hemodynamic stability is one of the most important concerns for induction of anesthesia in patients undergoing cardiac surgery. Remimazolam tosilate is a new, ultra-short-acting benzodiazepine agent, with the advantages of rapid onset, rapid offset, and minimal cardiorespiratory depression. We aim to compare the effect of remimazolam tosilate and etomidate on hemodynamics during anesthesia induction in patients undergoing valve replacement surgery.

METHODS/DESIGN

The trial is a prospective, randomized, double-blinded, controlled, single-center trial to compare the effect of remimazolam tosilate and etomidate on hemodynamics in patients undergoing valve replacement surgery. One hundred seventeen patients undergoing selective valve replacement surgery between January 1, 2022, and December 31, 2023, will be enrolled and randomly allocated into one of three groups: low-dose remimazolam group (Group LR), high-dose remimazolam group (Group HR), or etomidate group (Group E). The primary outcome is hemodynamic fluctuations during anesthesia induction (the difference between mean arterial pressure [MAP] to baseline, ▴MAP; and the difference between maximum or minimum heart rate [HR] and baseline, ▴HR). Secondary outcomes include the incidence of adverse cardiovascular events (hypotension, severe bradycardia, hypertension, tachycardia, and arrhythmia), the cumulative doses of vasoactive drugs used per patient, incidence and degree of injection pain and myoclonus, blood glucose values, and vital signs at different time points.

DISCUSSION

This research will determine the effectiveness and safety of remimazolam tosilate induction on hemodynamics in patients undergoing valve replacement surgery.

TRIAL REGISTRATION

www.chictr.org .cn identifier ChiCTR2100052535 . Registered on 17th Dec 2021, http://www.chictr.org.cn/ ).

Effect of Etomidate vs Propofol for Total Intravenous Anesthesia on Major Postoperative Complications in Older Patients: A Randomized Clinical Trial

Question

Does etomidate compared with propofol provide a noninferior effect on in-hospital morbidity when used for induction and maintenance of general anesthesia in older patients undergoing abdominal surgery?

Findings

In this randomized clinical trial involving 1944 older patients who underwent elective abdominal surgery, the rate of major in-hospital complications was noninferior between patients who received etomidate and those who received propofol for general anesthesia (9.3% vs 8.7%).

Meaning

Findings of this trial indicate that etomidate anesthesia does not increase postoperative morbidity in older patients compared with propofol.

Importance

Older patients may benefit from the hemodynamic stability of etomidate for general anesthesia. However, it remains uncertain whether the potential for adrenocortical suppression with etomidate may increase morbidity.

Objective

To test the primary hypothesis that etomidate vs propofol for anesthesia does not increase in-hospital morbidity after abdominal surgery in older patients.

Design, Setting, and Participants

This multicenter, parallel-group, noninferiority randomized clinical trial (Etomidate vs Propofol for In-hospital Complications [EPIC]) was conducted between August 15, 2017, and November 20, 2020, at 22 tertiary hospitals in China. Participants were aged 65 to 80 years and were scheduled for elective abdominal surgery. Patients and outcome assessors were blinded to group allocation. Data analysis followed a modified intention-to-treat principle.

Interventions

Patients were randomized 1:1 to receive either etomidate or propofol for general anesthesia by target-controlled infusion.

Main Outcomes and Measures

Primary outcome was a composite of major in-hospital postoperative complications (with a noninferiority margin of 3%). Secondary outcomes included intraoperative hemodynamic measurements; postoperative adrenocortical hormone levels; self-reported postoperative pain, nausea, and vomiting; and mortality at postoperative months 6 and 12.

Results

A total of 1944 participants were randomized, of whom 1917 (98.6%) completed the trial. Patients were randomized to the etomidate group (n = 967; mean [SD] age, 70.3 [4.0] years; 578 men [59.8%]) or propofol group (n = 950; mean [SD] age, 70.6 [4.2] years; 533 men [56.1%]). The primary end point occurred in 90 of 967 patients (9.3%) in the etomidate group and 83 of 950 patients (8.7%) in the propofol group, which met the noninferiority criterion (risk difference [RD], 0.6%; 95% CI, –1.6% to 2.7%; P = .66). In the etomidate group, mean (SD) cortisol levels were lower at the end of surgery (4.8 [2.7] μg/dL vs 6.1 [3.4] μg/dL; P < .001), and mean (SD) aldosterone levels were lower at the end of surgery (0.13 [0.05] ng/dL vs 0.15 [0.07] ng/dL; P = .02) and on postoperative day 1 (0.14 [0.04] ng/dL vs 0.16 [0.06] ng/dL; P = .001) compared with the propofol group. No difference in mortality was observed between the etomidate and propofol groups at postoperative month 6 (2.2% vs 3.0%; RD, –0.8%; 95% CI, –2.2% to 0.7%) and 12 (3.3% vs 3.9%; RD, –0.6%; 95% CI, –2.3% to 1.0%). More patients had pneumonia in the etomidate group than in the propofol group (2.0% vs 0.3%; RD, 1.7%; 95% CI, 0.7% to 2.8%; P = .001). Results were consistent in the per-protocol population.

Conclusions and Relevance

Results of this trial showed that, compared with propofol, etomidate anesthesia did not increase overall major in-hospital morbidity after abdominal surgery in older patients, although it induced transient adrenocortical suppression.

Trial Registration

ClinicalTrials.gov Identifier: NCT02910206

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.

Transforming Anesthesia Data Into the Observational Medical Outcomes Partnership Common Data Model: Development and Usability Study

BACKGROUND

Electronic health records (EHRs, such as those created by an anesthesia management system) generate a large amount of data that can notably be reused for clinical audits and scientific research. The sharing of these data and tools is generally affected by the lack of system interoperability. To overcome these issues, Observational Health Data Sciences and Informatics (OHDSI) developed the Observational Medical Outcomes Partnership (OMOP) common data model (CDM) to standardize EHR data and promote large-scale observational and longitudinal research. Anesthesia data have not previously been mapped into the OMOP CDM.

OBJECTIVE

The primary objective was to transform anesthesia data into the OMOP CDM. The secondary objective was to provide vocabularies, queries, and dashboards that might promote the exploitation and sharing of anesthesia data through the CDM.

METHODS

Using our local anesthesia data warehouse, a group of 5 experts from 5 different medical centers identified local concepts related to anesthesia. The concepts were then matched with standard concepts in the OHDSI vocabularies. We performed structural mapping between the design of our local anesthesia data warehouse and the OMOP CDM tables and fields. To validate the implementation of anesthesia data into the OMOP CDM, we developed a set of queries and dashboards.

RESULTS

We identified 522 concepts related to anesthesia care. They were classified as demographics, units, measurements, operating room steps, drugs, periods of interest, and features. After semantic mapping, 353 (67.7%) of these anesthesia concepts were mapped to OHDSI concepts. Further, 169 (32.3%) concepts related to periods and features were added to the OHDSI vocabularies. Then, 8 OMOP CDM tables were implemented with anesthesia data and 2 new tables (EPISODE and FEATURE) were added to store secondarily computed data. We integrated data from 5,72,609 operations and provided the code for a set of 8 queries and 4 dashboards related to anesthesia care.

CONCLUSIONS

Generic data concerning demographics, drugs, units, measurements, and operating room steps were already available in OHDSI vocabularies. However, most of the intraoperative concepts (the duration of specific steps, an episode of hypotension, etc) were not present in OHDSI vocabularies. The OMOP mapping provided here enables anesthesia data reuse.

Preintervention imaging and intraoperative management care of the hypertrophic obstructive cardiomyopathy patient

With an estimated overall mortality of less than 1 percent per year, hypertrophic cardiomyopathy, is the most common genetic cardiomyopathy. Intraoperative transesophageal echocardiography is the standard of care for assessing patients with hypertrophic obstructive cardiomyopathy undergoing surgical septal myectomy, allowing surgical planning, intraoperative hemodynamic monitoring, and postprocedural assessment of the repair, including detection of immediate complications. At various phases during surgical septal myectomy, the changing hemodynamic conditions may lead to worsening or improvement in left ventricle outflow tract obstruction by change in preload or afterload, systolic anterior motion of the mitral valve, or sympathetic stimulation. These characteristics represent unique challenges in the management of these patients, requiring a comprehensive understanding of the management of all the conditions required to decrease the left ventricle outflow tract gradient avoiding obstruction, which include the maintenance of sinus rhythm, adequate rate avoiding tachycardia and bradycardia, and avoidance of systemic hypotension preserving preload and afterload, with adequate vasoactive agents. The aim of this review is to summarize the perioperative assessment and management of patients undergoing hypertrophic obstructive myopathy surgery.

Etomidate and its Analogs: A Review of Pharmacokinetics and Pharmacodynamics

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

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.

Current status of perioperative hypnotics, role of benzodiazepines, and the case for remimazolam: a narrative review

Anaesthesiologists and non-anaesthesiologist sedationists have a limited set of available i.v. hypnotics, further reduced by the withdrawal of thiopental in the USA and its near disappearance in Europe. Meanwhile, demand for sedation increases and new clinical groups are using what traditionally are anaesthesiologists' drugs. Improved understanding of the determinants of perioperative morbidity and mortality has spotlighted hypotension as a potent cause of patient harm, and practice must be adjusted to respect this. High-dose propofol sedation may be harmful, and a critical reappraisal of drug choices and doses is needed. The development of remimazolam, initially for procedural sedation, allows reconsideration of benzodiazepines as the hypnotic component of a general anaesthetic even if their characterisation as i.v. anaesthetics is questionable. Early data suggest that a combination of remimazolam and remifentanil can induce and maintain anaesthesia. Further work is needed to define use cases for this technique and to determine the impact on patient outcomes.

CON: Propofol Is Better Than Etomidate for Induction in Cardiac Surgical Patients

There is an ongoing debate regarding the choice of ideal induction agent between propofol and etomidate for cardiac surgical patients. Etomidate appears to be better than propofol as the induction agent due to the superior hemodynamic stability. However, the adrenal suppression due to etomidate can pose challenges to the anesthesiologist in certain clinical situations.

Etomidate vs propofol in coronary heart disease patients undergoing major noncardiac surgery: A randomized clinical trial

BACKGROUND

The ideal depth of general anesthesia should achieve the required levels of hypnosis, analgesia, and muscle relaxation while minimizing physiologic responses to awareness. The choice of anesthetic strategy in patients with coronary heart disease (CHD) undergoing major noncardiac surgery is becoming an increasingly important issue as the population ages. This is because general anesthesia is associated with a risk of perioperative cardiac complications and death, and this risk is much higher in people with CHD.

AIM

To compare hemodynamic function and cardiovascular event rate between etomidate- and propofol-based anesthesia in patients with CHD.

METHODS

This prospective study enrolled consecutive patients (American Society of Anesthesiologists grade II/III) with stable CHD (New York Heart Association class I/II) undergoing major noncardiac surgery. The patients were randomly allocated to receive either etomidate/remifentanil-based or propofol/remifentanil-based general anesthesia. Randomization was performed using a computer-generated random number table and sequentially numbered, opaque, sealed envelopes. Concealment was maintained until the patient had arrived in the operating theater, at which point the consulting anesthetist opened the envelope. All patients, data collectors, and data analyzers were blinded to the type of anesthesia used. The primary endpoints were the occurrence of cardiovascular events (bradycardia, tachycardia, hypotension, ST-T segment changes, and ventricular premature beats) during anesthesia and cardiac troponin I level at 24 h. The secondary endpoints were hemodynamic parameters, bispectral index, and use of vasopressors during anesthesia.

RESULTS

The final analysis included 40 patients in each of the propofol and etomidate groups. The incidences of bradycardia, hypotension, ST-T segment changes, and ventricular premature beats during anesthesia were significantly higher in the propofol group than in the etomidate group (P < 0.05 for all). The incidence of tachycardia was similar between the two groups. Cardiac troponin I levels were comparable between the two groups both before the induction of anesthesia and at 24 h after surgery. When compared with the etomidate group, the propofol group had significantly lower heart rates at 3 min after the anesthetic was injected (T1) and immediately after tracheal intubation (T2), lower systolic blood pressure at T1, and lower diastolic blood pressure and mean arterial pressure at T1, T2, 3 min after tracheal intubation, and 5 min after tracheal intubation (P < 0.05 for all). Vasopressor use was significantly more in the propofol group than in the etomidate group during the induction and maintenance periods (P < 0.001).

CONCLUSION

In patients with CHD undergoing noncardiac major surgery, etomidate-based anesthesia is associated with fewer cardiovascular events and smaller hemodynamic changes than propofol-based anesthesia.

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.

Perioperative pharmacotherapy to prevent cardiac complications in patients undergoing noncardiac surgery

Introduction: Despite advances in surgical and anesthetic techniques, perioperative cardiovascular complications are a major cause of 30-day perioperative mortality. Major cardiovascular complications after noncardiac surgery include myocardial ischemia, congestive heart failure, arrhythmias, and cardiac arrest. Along with surgical risk assessment, perioperative medical optimization can reduce the rates and clinical impact of these complications.Areas Covered: In this review, the authors discuss the pharmacological basis, existing evidence, and professional society recommendations for drug management in preventing cardiovascular complications in patients undergoing noncardiac surgery.Expert opinion: Perioperative management of cardiovascular disease is an increasingly important and growing area of clinical practice. Societal guidelines regarding the use of most routine cardiovascular medications are based on a number of large clinical studies and provide a basic foundation to guide management. However, the heterogeneous nature of patients, as well as surgeries, makes it practically impossible to devise a 'one size fits all' recommendation in this setting. Thus, the importance of a more individualized approach to perioperative risk stratification and management is being increasingly recognized. The underlying comorbidities and cardiac profile as well as the risk of cardiac complications associated with the planned surgery must be factored in to understand the nuance of the management strategies.

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.

Ketamine for rapid sequence intubation in adult trauma patients: A retrospective observational study

BACKGROUND

In the trauma population, ketamine is commonly used during rapid sequence induction. However, as ketamine has been associated with important side effects, this study sought to compare in-hospital mortality in trauma patients after induction with ketamine versus other induction agents.

METHODS

We retrospectively identified adult trauma patients intubated in the pre-hospital phase or initially in the trauma bay at two urban level-1 trauma centers during a 2-year period using local trauma registries and medical records. In-hospital mortality was compared for patients intubated with ketamine versus other agents using logistic regression with adjustment for age, gender, Injury Severity Score (ISS), systolic blood pressure (SBP) < 90 mm Hg, and pre-hospital Glasgow Coma Scale (GCS) score.

RESULTS

A total of 343 trauma patients were included with a median ISS of 25 [17-34]. The most frequently used induction agents were ketamine (36%) and propofol (36%) followed by etomidate (9%) and midazolam (5%). There was no difference in ISS or the presence of SBP <90 mm Hg according to the agent of choice, but the pre-hospital GCS score was higher for patients intubated with ketamine (median 8 vs 5, P = .001). The mortality for patients intubated with ketamine was 18% vs 27% for patients intubated with other agents (P = .14). This remained statistically insignificant in the multivariable logistic regression analysis (odds ratio 0.68 [0.33-1.41], P = .30).

CONCLUSIONS

We found no statistically significant difference in mortality among patients intubated in the initial phase post-trauma with the use of ketamine compared with other agents (propofol, etomidate, or midazolam).

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.

The effect of midazolam or lidocaine administration prior to etomidate induction of anesthesia on heart rate, arterial pressure, intraocular pressure and serum cortisol concentration in healthy dogs

OBJECTIVE

To evaluate selected effects of midazolam or lidocaine administered prior to etomidate for co-induction of anesthesia in healthy dogs.

STUDY DESIGN

Prospective crossover experimental study.

ANIMALS

A group of 12 healthy adult female Beagle dogs.

METHODS

Dogs were premedicated with intravenous (IV) butorphanol (0.3 mg kg^-1), and anesthesia was induced with etomidate following midazolam (0.3 mg kg^-1), lidocaine (2 mg kg^-1) or physiologic saline (1 mL) IV. Heart rate (HR), arterial blood pressure, respiratory rate (f_R) and intraocular pressure (IOP) were recorded following butorphanol, after co-induction administration, after etomidate administration and immediately following intubation. Baseline IOP values were also obtained prior to sedation. Etomidate dose requirements and the presence of myoclonus, as well as coughing or gagging during intubation were recorded. Serum cortisol concentrations were measured prior to premedication and 6 hours following etomidate administration.

RESULTS

Blood pressure, f_R and IOP were similar among treatments. Blood pressure decreased in all treatments following etomidate administration and generally returned to sedated values following intubation. HR increased following intubation with midazolam and lidocaine but remained stable in the saline treatment. The dose of etomidate (median, interquartile range, range) required for intubation was lower following midazolam (2.2, 2.1-2.6, 1.7-4.1 mg kg^-1) compared with lidocaine (2.7, 2.4-3.6, 2.2-5.1 mg kg^-1, p = 0.012) or saline (3.0, 2.8-3.8, 1.9-5.1 mg kg^-1, p = 0.015). Coughing or gagging was less frequent with midazolam compared with saline. Myoclonus was not observed. Changes in serum cortisol concentrations were not different among treatments.

CONCLUSIONS AND CLINICAL RELEVANCE

Midazolam administration reduced etomidate dose requirements and improved intubation conditions compared with lidocaine or saline treatments. Neither co-induction agent caused clinically relevant differences in measured cardiopulmonary function, IOP or cortisol concentrations compared with saline in healthy dogs. Apnea was noted in all treatments following the induction of anesthesia and preoxygenation is recommended.

Effect of dexmedetomidine on etomidate-induced myoclonus: a randomized, double-blind controlled trial

Background: Etomidate used for the induction of general anesthesia can result in myoclonus. We tested the hypothesis that pretreatment with dexmedetomidine (Dex) reduces the incidence of etomidate-induced myoclonus during the induction of general anesthesia.

Materials and methods: One hundred patients who were scheduled for selective operations under general anesthesia were included in this randomized, double-blind controlled trial. Patients were randomized to receive either Dex 0.5 µg/kg in 20 mL of normal saline or the same volume of normal saline as pretreatment agents 15 mins before the injection of etomidate 0.3 mg/kg. The primary endpoint was the incidence of etomidate-induced myoclonus. Secondary endpoints were the severity of etomidate-induced myoclonus and the incidence of adverse effects from the onset of action of Dex or normal saline to the injection of etomidate, such as dizziness, respiratory depression, bradycardia, hypotension and nausea/vomiting.

Results: All of the 100 patients completed the trial. Dex resulted in a significant 38% reduction in the number of patients who experienced etomidate-induced myoclonus: 13 (26%) vs 32 (64%) (P=0.0001). Additionally, the severity of myoclonus was also reduced in the Dex group than that in the placebo group (P=0.02). Incidence of dizziness, respiratory depression, bradycardia, hypotension and nausea/vomiting was similar in both groups.

Conclusions: Pretreatment with Dex 0.5 µg/kg 15 mins before the induction of general anesthesia not only resulted in a 38% reduction in the incidence of etomidate-induced myoclonus, but also reduced the severity of myoclonus, without inducing any adverse effects.

Anesthesiologist and Emergency Medicine Physician Attitudes and Knowledge Regarding Etomidate for Intubation

PURPOSE

The use of etomidate as an induction agent for critically ill patients is controversial. While its favorable hemodynamic profile is enviable, etomidate has been shown to cause transient adrenal suppression. The clinical consequences of transient adrenal suppression are poorly understood. Anecdotally, some clinicians advocate strongly for etomidate, while others feel it can cause significant harm. To better understand the current clinical environment with respect to single-dose etomidate use in critically ill patients, Canadian anesthesiologists and Canadian emergency medicine (EM) physicians were questioned regarding their opinions, knowledge, and preferences about etomidate use as an induction agent.

METHODS

Invitations to participate with the electronic survey were sent to 100 Canadian EM physicians and 260 Canadian anesthesiologists. The survey had 4 general parts: demographics, familiarity with the current literature, choice of induction agent given various clinical scenarios, and opinions on the controversy. The Pearson γ² test was used to detect whether significant differences exist between physician groups.

RESULTS

Ninety three anesthesiologists and 42 EM physicians responded for response rates of 36% and 42%. There were no self-reported differences in knowledge about etomidate properties between EM physicians and anesthesiologists. There were significant differences in etomidate use between EM physicians and anesthesiologists in general rapid sequence intubation, noncritically ill patients, and those with undifferentiated hypotension. Both EM physicians and anesthesiologists describe the current etomidate controversy as significant and not adequately resolved.

CONCLUSION

There is no significant difference in self-reported etomidate knowledge between anesthesiologists and EM physicians; however, significant practice pattern differences exist with EM physicians using etomidate more often. Broad agreement supports future research to investigate etomidate's impact in critically ill patients.

Comparing Hemodynamic Responses to Diazepam, Propofol and Etomidate During Anesthesia Induction in Patients with Left Ventricular Dysfunction Undergoing Coronary Artery Bypass Graft Surgery: a Double-blind, Randomized Clinical Trial

Background:

Anesthesia induction is often accompanied by a period of hemodynamic instability, which could be deleterious in patients with coronary artery disease (CAD) and left ventricular dysfunction undergoing coronary artery bypass graft (CABG) surgery. The aim of this study was to compare the hemodynamic responses to propofol, etomidate, and diazepam following anesthesia induction, laryngoscopy and intubation in CABG surgery patients with low ejection fraction (EF).

Methods:

A double-blind randomized, clinical study was performed on 150 patients with CAD and left ventricular dysfunction (EF≤35%) scheduled for elective CABG surgery with Cardiopulmonary bypass (CPB). Patients were randomly allocated to three groups A, B, and C. These patients received propofol, etomidate or diazepam at induction of anesthesia, respectively. Hemodynamic variables (systolic and diastolic blood pressure [SBP, DBP], mean arterial pressure [MAP] and heart rate [HR]) were measured and recorded at baseline, immediately before laryngoscopy and tracheal intubation and one and three minutes after intubation.

Result:

One minute after induction and before laryngoscopy, there was a statistically significant decrease from the baseline in SBP, DBP and MAP in all three groups, but these variables in each hemodynamic parameters in diazepam group were less than other two groups (p<0.001). Moreover, the mean HR decreased in patients receiving propofol and etomidate one minute after induction and before laryngoscopy, but did not decreased in the diazepam group (p=0.005).

Conclusion:

The present study showed that in patients undergoing CABG surgery with low EF, diazepam is more favorable in terms of hemodynamic stability compared to propofol and etomidate and this drug can be used safely for induction of anesthesia in patients with impaired ventricular function.

Current evidence for anesthesia management during endovascular stroke therapy: updated systematic review and meta-analysis

Introduction

Debate continues about the optimal anesthetic management for patients undergoing endovascular treatment (ET) of acute ischemic stroke due to emergent large vessel occlusion.

Objective

To compare, using current evidence, the clinical outcomes and procedural characteristics among patients undergoing general anesthesia (GA) and local or monitored anesthesia (non-GA).

Methods

We performed a systematic review and meta-analysis of all available studies that involved the use of stent retrievers for ET (stentriever group). Additionally, we included studies that were published in 2015 and later, and compared the clinical outcomes among the studies using stentrievers or no stentrievers (pre-stentriever group). Outcome variables included functional independence (FI; modified Rankin Scale scores of 0–2), symptomatic hemorrhage, mortality, procedure duration, and vascular and respiratory complications. We calculated pooled odds ratios and 95% CIs using random-effects models.

Results

Sixteen studies (three randomized controlled clinical trials (RCTs) and 13 non-randomized studies) were identified comprising 5836 patients. Although non-GA was associated with higher odds of 3-month FI (OR=1.57; 95% CI 1.17 to 2.10; P=0.003) and lower odds of 3-month mortality (OR=0.62; 95% CI 0.47 to 0.82; P=0.0006, substantial heterogeneity was noted across included trials. Sensitivity analyses of RCTs showed that non-GA was inversely associated with FI (OR=0.55; 95% CI 0.34 to 0.89; P=0.01; I2=15%), while no association was noted with mortality (OR=1.36; 95% CI 0.79 to 2.34; P=0.27; I2=0%).

Conclusion

Our updated meta-analysis demonstrates favorable results with non-GA, probably owing to inclusion of non-randomized studies. Recent single-center RCTs indicate that GA is associated with higher odds of FI at 3 months, while other outcomes are similar between the two groups.

Predictors of major complications after elective abdominal surgery in cancer patients

Background

Patients undergoing abdominal surgery for solid tumours frequently develop major postoperative complications, which negatively affect quality of life, costs of care and survival. Few studies have identified the determinants of perioperative complications in this group.

Methods

We performed a prospective observational study including all patients (age > 18) undergoing abdominal surgery for cancer at a single institution between June 2011 and August 2013. Patients undergoing emergency surgery, palliative procedures, or participating in other studies were excluded. Primary outcome was a composite of 30-day all-cause mortality and infectious, cardiovascular, respiratory, neurologic, renal and surgical complications. Univariate and multiple logistic regression analyses were performed to identify predictive factors for major perioperative adverse events.

Results

Of a total 308 included patients, 106 (34.4%) developed a major complication during the 30-day follow-up period. Independent predictors of postoperative major complications were: age (odds ratio [OR] 1.03 [95% CI 1.01–1.06], p = 0.012 per year), ASA (American Society of Anesthesiologists) physical status greater than or equal to 3 (OR 2.61 [95% CI 1.33–5.17], p = 0.003), a preoperative haemoglobin level lower than 12 g/dL (OR 2.13 [95% CI 1.21–4.07], p = 0.014), intraoperative use of colloids (OR 1.89, [95% CI 1.03–4.07], p = 0.047), total amount of intravenous fluids (OR 1.22 [95% CI 0.98–1.59], p = 0.106 per litre), intraoperative blood losses greater than 500 mL (2.07 [95% CI 1.00–4.31], p = 0.043), and hypotension needing vasopressor support (OR 4.68 [95% CI 1.55–27.72], p = 0.004). The model had good discrimination with the area under the ROC curve being 0.80 (95% CI 0.75–0.84, p < 0.001).

Conclusions

Our findings suggest that a perioperative strategy aimed at reducing perioperative complications in cancer surgery should include treatment of preoperative anaemia and an optimal fluid strategy, avoiding fluid overload and intraoperative use of colloids.

Electronic supplementary material

The online version of this article (10.1186/s12871-018-0516-6) contains supplementary material, which is available to authorized users.

Steroid administration after anaesthetic induction with etomidate does not reduce in-hospital mortality or cardiovascular morbidity after non-cardiac surgery

BACKGROUND

We tested the primary hypothesis that corticosteroid administration after etomidate exposure reduces a composite of in-hospital mortality and cardiovascular morbidity after non-cardiac surgery.

METHODS

We evaluated ASA physical status III and IV patients who had non-cardiac surgery with general anaesthesia at the Cleveland Clinic. Amongst 4275 patients in whom anaesthesia was induced with etomidate, 804 were also given steroid intraoperatively, mostly dexamethasone at a median dose of 6 mg. We successfully matched 582 steroid patients with 1023 non-steroid patients. The matched groups were compared on composite of in-hospital mortality and cardiovascular morbidity using a generalized-estimating-equation model. Secondly, the matched groups were compared on length of hospital stay using a Cox proportional hazard model, and were descriptively compared on intraoperative blood pressures using a standardized difference.

RESULTS

There was no significant association between intraoperative steroid administration after anaesthetic induction with etomidate and the composite of in-hospital mortality or cardiovascular morbidity; the estimated common odds ratio across the two components of the composite was 0.86 [95% confidence interval (CI): 0.64, 1.16] for steroid vs non-steroid, P=0.33. The duration of postoperative hospitalisation was significantly shorter amongst steroid patients [median (Q1, Q3): 6 (3, 10) days] than non-steroid patients [7 (4, 11) days], with an estimated hazard ratio of 0.89 (0.80, 0.98) for steroid vs non-steroid, P=0.01. Intraoperative blood pressures were similar in steroid and non-steroid patients.

CONCLUSIONS

Steroid administration after induction of anaesthesia with etomidate did not reduce mortality or cardiovascular morbidity.

Pharmacologic studies on ET-26 hydrochloride in a rat model of lipopolysaccharide-induced sepsis

BACKGROUND

ET-26 hydrochloride (ET-26 HCl) is a promising sedation-hypnotic compound with stable hemodynamic features that elicits virtually no adrenocortical suppression. However, whether it preserves better pharmacologic characteristics in a rat model of sepsis is not known. This study compared the survival rate, levels of corticosterone and pro-inflammatory cytokines, and histologic injury in the lungs and kidneys of rats suffering from sepsis treated with ET-26 HCl, etomidate, or normal saline (NS).

METHODS

Rats were given lipopolysaccharide (1mg/kg body weight, i.v.) to establish a sepsis model. Thirty minutes after lipopolysaccharide administration, ET-26 HCl, etomidate or NS were given as a bolus injection at equivalent doses. Plasma levels of corticosterone, interleukin-1β, interleukin-6, interleukin-10, and tumor necrosis factor-α were measured 1, 2, 4, 6 and 24h after administration. Histologic injury was observed at the time of death or 24h after drug administration.

RESULTS

The survival rate for rats in the etomidate, ET-26 HCl and NS groups was 40%, 90% and 90%, respectively. Corticosterone concentrations in the etomidate group were lower than those in the other groups 1h after administration of hypnotic compounds. Concentrations of pro-inflammatory cytokines in the ET-26 HCl group and NS group were not significantly different, but were significantly lower than those in the etomidate group. The injury scores of kidneys and lungs in the etomidate group were higher than those in ET-26 HCl and NS groups.

CONCLUSIONS

ET-26 HCl showed virtually no suppression of corticosterone synthesis, lower concentrations of pro-inflammatory cytokines, higher survival rate, and less organ injury in rats suffering from sepsis compared with the etomidate group. It may be safer to induce anesthesia using ET-26 HCl, rather than etomidate, in patients suffering from sepsis.

ET-26 hydrochloride (ET-26 HCl) has similar hemodynamic stability to that of etomidate in normal and uncontrolled hemorrhagic shock (UHS) rats

Objective

ET-26 HCl is a promising sedative–hypnotic anesthetic with virtually no effect on adrenocortical steroid synthesis. However, whether or not ET-26 HCl also has a sufficiently wide safety margin and hemodynamic stability similar to that of etomidate and related compounds remains unknown. In this study, the effects of ET-26 HCl, etomidate and propofol on therapeutic index, heart rate (HR), mean arterial pressure (MAP), maximal rate for left ventricular pressure rise (D_max/t), and maximal rate for left ventricular pressure decline (D_min/t) were investigated in healthy rats and a rat model of uncontrolled hemorrhagic shock (UHS).

Methods

50% effective dose (ED₅₀) and 50% lethal dose (LD₅₀) were determined after single bolus doses of propofol, etomidate, or ET-26 HCl using the Bliss method and the up and down method, respectively. All rats were divided into either the normal group and received either etomidate, ET-26 HCl or propofol, (n = 6 per group) or the UHS group and received either etomidate, ET-26 HCl or propofol, (n = 6 per group). In the normal group, after preparation for hemodynamic and heart-function monitoring, rats were administered a dose of one of the test agents twofold-higher than the established ED₅₀, followed by hemodynamic and heart-function monitoring. Rats in the UHS group underwent experimentally induced UHS with a target arterial pressure of 40 mmHg for 1 hour, followed by administration of an ED₅₀ dose of one of the experimental agents. Blood-gas analysis was conducted on samples obtained during equilibration with the experimental setup and at the end of the experiment.

Results

In the normal group, no significant differences in HR, MAP, D_max/t and D_min/t (all P > 0.05) were observed at any time point between the etomidate and ET-26 HCl groups, whereas HR, MAP and D_max/t decreased briefly and D_min/t increased following propofol administration. In the UHS group, no significant differences in HR, MAP, D_max/t and D_min/t were observed before and after administration of etomidate or ET-26 HCl at ED₅₀ doses (all P > 0.05). Administration of propofol resulted in brief, statistically significant reductions in HR and D_max/t, with a brief increase in D_min/t (P ˂ 0.05), while no significant differences in MAP were observed among the three groups. The blood-lactate concentrations of rats in the ET-26 HCl group were significantly lower than those in etomidate and propofol groups (P ˂ 0.05).

Conclusions

ET-26 HCl provides a similar level of hemodynamic stability to that obtained with etomidate in both healthy rats, and rat models of UHS. ET-26 HCl has the potential to be a novel induction anesthetic for use in critically ill patients.

A randomized clinical trial comparing hemodynamic responses to ketamine-propofol combination (ketofol) versus etomidate during anesthesia induction in patients with left ventricular dysfunction undergoing coronary artery bypass graft surgery

INTRODUCTION

Anesthesia induction is often accompanied by a period of hemodynamic instability, which could be a significant problem in patients with compromised ventricular function. The aim of this study is to compare the hemodynamic responses to etomidate versus a combination of ketamine and propofol (ketofol) for anesthetic induction in patients with left ventricular dysfunction undergoing coronary artery bypass graft (CABG) surgery.

MATERIAL AND METHODS

In a double-blind randomized clinical study, a total of 84 patients with ischemic left ventricular dysfunction (EF < 40%) were randomly assigned to two groups (A and B). Patients in group A received etomidate 0.2 mg/kg and a placebo (normal saline); group B received a combination of ketamine (1 mg/kg) and propofol (1.5 mg/kg) at the induction of anesthesia. Two minutes after induction, hemodynamic variables, including systolic, diastolic, mean arterial pressure (SAP, DAP, MAP) and heart rate (HR), were measured immediately before and after the laryngoscopy, and before intubation and post-intubation at 1, 2, and 3 min.

RESULTS

The decrease in all hemodynamic parameters (SBP, DBP, MAP and HR) from induction time to laryngoscopy was greater in the ketofol group (group B) than in the etomidate group (group A) (p < 0.05). The ephedrine prescription rate due to hemodynamic changes was 24.4% (10 patients) and 5% (2 patients) in group B and group A, respectively (p = 0.03).

CONCLUSIONS

We found that etomidate provides superior hemodynamic stability as compared to ketofol in patients with left ventricular dysfunction undergoing CABG surgery under general anesthesia.

Acute left ventricle failure on induction of anesthesia: a case report of reverse stress cardiomyopathy-presentation, diagnosis and treatment

Reverse takotsubo cardiomyopathy (TCM) is a less common variant of classic TCM that presents within a different patient profile and with its own hemodynamic considerations. A 46-year-old woman was admitted to our hospital for laryngoscopy and possible balloon dilatation for tracheal stenosis under general anesthesia. One year prior to this admission, the patient was admitted after a motor vehicle accident with subdural hematoma, subarachnoid hemorrhage, and fracture of the eighth thoracic vertebra. She underwent uneventful anesthesia for thoracic spine surgery and tracheostomy to help her wean from the ventilator during that admission. Since her previous admission, she developed posttraumatic anxiety and depression (a neuropsychiatric disorder triggered by subdural hematoma and subarachnoid hemorrhage) and was treated with antianxiety and antidepressant medication. At this admission, the patient developed acute left ventricle failure on induction of anesthesia secondary to reverse TCM. We report a case of reverse TCM, where posttraumatic emotional stress of a neuropsychiatric disorder combined with physical stress from anesthesia and laryngoscopy triggered TCM in a patient with previous uneventful anesthesia 1 year earlier.

The role of etomidate as an anaesthetic induction agent for critically ill patients

Etomidate is an anaesthetic induction agent which may be favoured in critically ill patients because of its cardiovascular stability. However, etomidate causes adrenocortical suppression which may be particularly harmful in these patients. This article reviews current evidence and debates the use of etomidate in critical illness.