Background: The consequences of inhibition of cortisol synthesis by a single dose of etomidate on subsequent vasopressor drug usage and the duration of relative adrenal insufficiency (RAI) after cardiac surgery are not known.
Methods: This was a prospective, randomized, double-blinded controlled trial of 100 patients undergoing elective cardiac surgery and receiving either etomidate or propofol at induction of anaesthesia. A short corticotropin test was performed 12, 24, and 48 h after anaesthesia induction. RAI was defined as a response <250 nmol litre(-1).
Results: The mean (sd) norepinephrine infusion rate during the first 48 postoperative hours was 0.11 (0.01) and 0.11 (0.01) µg kg(-1) min(-1) in the etomidate and propofol groups, respectively (P=0.89). Time to norepinephrine withdrawal was similar between the groups. The incidence of RAI was higher in the etomidate group at 12 h (100% vs 41%, P<0.001) and 24 h (85% vs 25%, P<0.001).
Conclusions: A single bolus of etomidate blunts the hypothalamic-pituitary-adrenal axis response for more than 24 h in patients undergoing elective cardiac surgery, but this was not associated with an increase in vasopressor requirements.