Comparison of clinical outcome variables in patients with and without etomidate-facilitated anesthesia induction ahead of major cardiac surgery: a retrospective analysis

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.

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.

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.

The Impact of Anesthetic Regimen on Outcomes in Adult Cardiac Surgery: A Narrative Review

Despite improvements in surgical techniques and perioperative care, cardiac surgery still is burdened by relatively high mortality and frequent major postoperative complications, including myocardial dysfunction, pulmonary complications, neurologic injury, and acute kidney injury. Although the surgeon's skills and volume and patient- and procedure-related risk factors play a major role in the success of cardiac surgery, there is growing evidence that also optimizing perioperative care may improve outcomes significantly. The present review focuses on the aspects of perioperative care that are strictly related to the anesthesia regimen, with special reference to volatile anesthetics and neuraxial anesthesia, whose effect on outcome in adult cardiac surgery has been investigated extensively.

Anaesthetic induction with etomidate in cardiac surgery: A randomised controlled trial

BACKGROUND

Etomidate is perceived as preserving haemodynamic stability during induction of anaesthesia. It is also associated with adrenocortical dysfunction. The risk/benefit relationship is controversial.

OBJECTIVES

We tested the hypotheses that single-dose etomidate increases cumulative vasopressor requirement, time to extubation and length of stay in the ICU.

DESIGN

Double-blind randomised controlled trial.

SETTING

Bern University Hospital, Switzerland, from November 2006 to December 2009.

PATIENTS

There were 90 patients undergoing coronary artery bypass grafts (CABG) and 40 patients undergoing mitral valve surgery (MVS). Reasons for noninclusion were known adrenocortical insufficiency, use of etomidate or propofol within 1 week preoperatively, use of glucocorticoids within 6 months preoperatively, severe renal or liver dysfunction, or carotid stenosis.

INTERVENTIONS

CABG patients were allocated randomly to receive either etomidate 0.15 mg kg with placebo, propofol 1.5 mg kg with placebo or etomidate 0.15 mg kg with hydrocortisone (n = 30 in each arm). Risk stratification (low vs. high) was achieved by block randomisation. MVS patients received either etomidate 0.15 mg kg or propofol 1.5 mg kg (n = 20 in each arm).

MAIN OUTCOME MEASURES

Cumulative vasopressor requirements, incidence of adrenocortical insufficiency, length of time to extubation and length of stay in ICU.

RESULTS

Cumulative vasopressor requirements 24 h after induction did not differ between treatments in patients who underwent CABG, whereas more noradrenaline was used in MVS patients following propofol induction (absolute mean difference 5.86 μg kg over 24 h P = 0.047). The incidence of relative adrenocortical insufficiency was higher after etomidate alone than propofol (CABG 83 vs. 37%, P < 0.001; MVS: 95 vs. 35%, P < 0.001). The time to extubation, length of stay in ICU and 30-day mortality did not differ among treatments. Within low and high-risk subgroups, no differences in vasopressor use or outcomes were found.

CONCLUSION

In elective cardiac surgery, laboratory indicators of etomidate-induced adrenal insufficiency do not translate into increased vasopressor requirement or inferior early outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT 00415701.

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.

Pulmonary Hypertensive Crisis on Induction of Anesthesia

Anesthesia for lung transplantation remains one of the highest risk surgeries in the domain of the cardiothoracic anesthesiologist. End-stage lung disease, pulmonary hypertension, and right heart dysfunction as well as other comorbid disease factors predispose the patient to cardiovascular, respiratory and metabolic dysfunction during general anesthesia. Perhaps the highest risk phase of surgery in the patient with severe pulmonary hypertension is during the induction of anesthesia when the removal of intrinsic sympathetic tone and onset of positive pressure ventilation can decompensate a severely compromised cardiovascular system. Severe hypotension, cardiac arrest, and death have been reported previously. Here we present 2 high-risk patients for lung transplantation, their anesthetic induction course, and outcomes. We offer suggestions for the safe management of anesthetic induction to mitigate against hemodynamic and respiratory complications.

Effects of continuous infusion of etomidate at various dose rates on adrenal function in dogs

BACKGROUND

Etomidate is a commonly used sedative in intravenous anesthesia. The aim of this study was to compare the effects of various etomidate doses administered by continuous infusion on adrenal function in dogs under general anesthesia.

METHODS

Thirty-six healthy adult male dogs were randomly divided into six groups. Sodium pentobarbital alone was administered to the control group (group C); five experimental groups (E1, E2, E3, E4, and E5) were also given etomidate at doses of 10, 15, 20, 25, and 30 μg · kg(-1) · min(-1), respectively, to maintain anesthesia. Heart rate (HR), mean arterial pressure (MAP), and bispectral index (BIS) were monitored. Serum cortisol, aldosterone, adrenaline, and noradrenaline levels were measured, and HR, MAP, and BIS values recorded, before intubation (T0), and at 1 h, 2 h, and 3 h after intubation (T1-3).

RESULTS

Cortisol and aldosterone levels in groups E1-5 decreased as the doses and times of continuous infusion of etomidate increased. The cortisol level was significantly decreased compared with baseline at T3 in group E1 and at T1-3 in groups E2-5 (P < 0.05). Compared with the corresponding levels in group C, cortisol levels were significantly lower than T0 values at T3 in group E1 and at T1-3 in groups E2-5 (P < 0.05). The aldosterone level was significantly lower at T3 in group E2 and at T1-3 in groups E3-5 (P < 0.05). Significant reductions in cortisol levels at T2-3 in group E2 and at T1-3 in groups E3-5 compared with group C were also observed (P < 0.05). The plasma adrenaline and noradrenaline levels, HR, MAP, and BIS in groups E1-5 were within the normal range at the different times and with the different doses (P > 0.05).

CONCLUSIONS

Cortisol and aldosterone levels decreased with time and continuous infusion of etomidate; there were no significant changes in adrenaline and noradrenaline levels, HR, MAP, and BIS in any group.

Etomidate in pediatric anesthesiology: Where are we now?

Etomidate is an intravenous anesthetic agent released for clinical use in the United States in 1972. Its popularity in clinical practice is the result of its beneficial effects on intracerebral dynamics with limited effects on hemodynamic function. These properties have made it a safe and effective anesthetic induction agent in both adult and pediatric patients with altered myocardial performance, congenial heart disease, or hypovolemia. However, recent concern has been expressed regarding its effects on the endogenous production of corticosteroids and the impact of that effect on patient outcomes. The following manuscript reviews clinical reports regarding etomidate use in the pediatric population and discusses recent concerns regarding its effects on corticosteroid metabolism and the implications of such effects for clinical use.

Etomidate for anesthesia induction: friends or foe in major cardiac surgery?

Use of etomidate for anesthesia induction is still debated. In the previous issue of Critical Care, Heinrich and colleagues reported that etomidate for anesthesia induction had similar outcome in comparison with other drugs, in a specific population of 3,054 patients ahead of major cardiac surgery. For the authors, the similar outcomes for mortality and length of hospital stay add to the hemodynamic stability and the improved intubation conditions to support keeping etomidate in the emergency drugs armamentarium for induction of anesthesia in patients at risk of hemodynamic failure. This commentary reviews the results and implications of their study.