Effect of a single dose of etomidate on adrenal function in patients with trauma

Studies investigating the relationship between adrenal insufficiency in sepsis and the potential need for steroids have been complicated by the use of etomidate, an anaesthetic agent that has been shown to cause adrenal impairment. Controversy still exists regarding the effects of a single dose of etomidate on adrenal function and a temporal or dose-dependent effect may occur. In an attempt to remove the confounding effect of sepsis on adrenal function, we studied a group of severely injured trauma patients to determine whether a single dose of etomidate effects adrenal function.

Trauma patients admitted to the intensive care unit of the Royal London Hospital who had received etomidate as their induction agent were enrolled within 36 hours of admission. Patients received varying doses of etomidate on induction. Plasma cortisol was measured at baseline and 60 min following a short ACTH stimulation test (250 μg synthetic ACTH). Responders were defined as having an increment in cortisol of > 250 nmol/l. Data were analysed using an unpaired t test or chi-square test as appropriate.

Twenty-two patients (17 male) with polytrauma were recruited. Nine patients had impaired adrenal function. Overall, compared with responders, there was no difference between dose of etomidate received or time from induction (Table 1).

Table 1 Table 1

There was no difference in incidence of adrenal impairment in those patients who had their adrenal function assessed pre or post 18 hours from receiving etomidate.

In conclusion, patients with severe polytrauma who have received etomidate commonly have adrenal impairment. The clinical significance of these findings is unclear but it is not possible to exclude an inhibitory effect of etomidate on adrenal function. Prior to commencing steroids in the critically ill with adrenal insufficiency, it is important to consider whether patients have received etomidate.