Prophylactic norepinephrine infusion to reduce severe hypotension during induction of anaesthesia in patients undergoing cardiac surgery: a randomised controlled single-centre clinical trial.

Abstract

The EPITUBE trial aimed to determine whether a prophylactic infusion of norepinephrine reduced severe hypotension after induction of general anaesthesia and tracheal intubation in patients undergoing cardiac surgery. We performed a randomised controlled single-centre clinical trial including patients undergoing cardiac surgery. In the experimental group, infusion of norepinephrine started from the start of preoxygenation at an infusion rate of 0.06 μg kg^-1 min^-1, secondarily titrated to maintain mean arterial pressure (MAP) between 65 and 80 mm Hg. In the control group, ephedrine was administered if MAP decreased <65 mm Hg. Primary outcome was the occurrence of MAP <55 mm Hg. Secondary measures included tracheal intubation-related complications, postoperative complications, duration of ICU stay, and mortality. Of 210 patients randomised and analysed in the intention-to-treat analysis, the incidence of severe hypotension was not different between the groups: 43.8% in the norepinephrine group vs 44.8% in the control group (odds ratio 0.96, 95% confidence interval [CI] 0.56-1.66, P=0.99). The incidence of MAP <65 mm Hg was lower in the norepinephrine group than in the control group: 63.8% vs 78.1% (odds ratio 0.49, 95% CI 0.26-0.90, P=0.02). The rate of intubation-related complications was not different between the norepinephrine and control groups, 22.9% vs 32.4%, respectively (odds ratio 0.62, 95% CI 0.33-1.14, P=0.13). There was no difference in postoperative outcomes including acute kidney injury, time on ventilator, or length of stay in the ICU. In patients undergoing cardiac surgery, infusion of norepinephrine before general anaesthesia at a starting dose of 0.06 μg kg^-1 min^-1 did not reduce severe hypotension compared with on-demand ephedrine. ClinicalTrials.gov Identifier: NCT05335954.