Effect of discontinuing antihypertensives on perioperative hypotension in older patients before non-cardiac surgery: multicentre, randomised, double blind, controlled trial

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A randomized trial across five hospitals in China found that withholding ACE inhibitors or ARBs on the morning of non-cardiac surgery reduced perioperative hypotension in older patients. It did not significantly change postoperative hypotension, 30-day complications, or mortality compared with continuing the medications.

AbstractObjectiveTo determine whether discontinuing versus continuing angiotensin converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) on the morning of surgery reduces perioperative hypotension in older patients undergoing non-cardiac surgery.DesignMulticentre, randomised, double blind, placebo controlled trial.SettingFive tertiary teaching hospitals in China, November 2020 to December 2023.Participants2036 older patients (60-80 years) using ACE inhibitors or ARBs for at least two weeks and scheduled for non-cardiac surgery under general anaesthesia.InterventionsPatients were randomised to receive their usual ACE inhibitor or ARB or a placebo in identical capsules on the morning of surgery.Main outcome measuresThe primary outcome was the incidence of perioperative hypotension (mean blood pressure <65 mm Hg or a ≥30% decrease from baseline requiring treatment). Secondary outcomes included duration of hypotension, requirement for a vasopressor, intraoperative fluid volume, postoperative hypotension, and 30 day complications (neurocognitive disorders, major cardiocerebral events) or mortality.Results2012 patients (mean age 68.8 years; 54.4% male) completed the study: 1004 were included in the antihypertensive group and 1008 in the no antihypertensive group. The incidence of perioperative hypotension was lower in the no antihypertensive group (314/1008, 31.2%) versus antihypertensive group (457/1004, 45.5%): adjusted odds ratio 0.52 (95% confidence interval (CI) 0.43 to 0.63); absolute risk difference -14.4% (95% CI -18.5% to -10.1%); P<0.001. The duration of hypotension and requirement for a vasopressor were both reduced in the no antihypertensive group: adjusted mean difference -1.3 minutes (95% CI -1.8 to -0.8 minutes) and 28.5% v 41.1%; adjusted odds ratio 0.54 (95% CI 0.44 to 0.66). Intraoperative fluid volume, postoperative hypotension, 30 day complications, and mortality did not differ significantly between groups.ConclusionsDiscontinuing ACE inhibitors or ARBs on the morning of surgery in older patients with hypertension statistically significantly reduced perioperative hypotension and the requirement for vasopressors without increasing 30 day complications or mortality. This simple strategy provides high certainty evidence for preoperative drug management in this patient population.Trial registrationChinese Clinical Trial Registry ChiCTR2000039376.