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

Objective:To systematically review the effects of etomidate(ETM)administered during anesthesia induction on patients undergoing cardiac surgery.Methods:Electronic databases Pubmed,Cochrane Library,OVID and EMBASE were searched to identify all randomized controlled trials(RCTs)comparing ETM with Control on hemodynamic profiles(e.g.blood pressure,heart rate,myocardial function),stress responses(cortisol,catecholamines)and outcomes(e.g.morbidity,mortality,post-operative recovery)of cardiac surgical patients.Two authors independently extracted relevant variables and outcome data.Continuous variables were pooled as weighted mean difference(WMD)and 95%confidential interval(CI).Dichotomous variables were calculated as odds ratio(OR)and 95%CI.Randomized-effects model was used for outcomes with significant heterogeneity,otherwise fixed-effects model was used.Sensitivity analyses were performed by transforming statistical model and eliminating individual trial(s)to assess the influence on overall effect.Publication bias was estimated through visual inspection on distribution of included studies on funnel plots.Statistical significance was defined as P<0.05.Results:A database search yielded 18 randomized controlled trials including 1,241 patients.The present meta-analysis demonstrated that ETManesthetized 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.Conclusions:The present meta-analysis suggested that,single-dose ETM administered during anesthesia induction was 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.