The effect of anaesthetic induction with etomidate on the endocrine response to surgical trauma

In order to investigate the effects of anaesthetic induction with a single bolus dose of etomidate on the endocrine response to a standard surgical stress, five patients were randomly allocated to receive etomidate and five to receive thiopentone as an induction agent prior to elective inguinal hernia repair. The group receiving etomidate showed a significant suppression in the circulating level of cortisol at 90 and 120 min post-induction (P less than 0.001) and an elevation in their plasma adrenocorticotrophic hormone at 240 and 360 min post-induction (P less than 0.001). The effect of a bolus dose of etomidate upon circulating cortisol levels was transient and no cardiovascular instability was noted during the study. The etomidate group also showed suppression of their circulating testosterone levels at 90 min post-induction (P less than 0.001), suggesting that etomidate inhibits steroidogenesis at a site other than 11 beta-hydroxylase.