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

Abstract

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.