Discontinuation of renin-angiotensin system inhibitors before non-cardiac surgery: a meta-analysis

The best management approach for renin-angiotensin system (RAS) inhibitor use before surgery is controversial. Some studies have suggested that continuation could increase the risk of clinically significant peri-operative hypotension and, thus, organ injury. By contrast, others believe that withholding them significantly increases the risk of severe hypertension and heart failure. To determine the most effective strategy, this systematic review and meta-analysis of randomized controlled trials compared discontinuation vs continuation of RAS inhibitors in patients undergoing non-cardiac and non-vascular surgeries.

PubMed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for randomized controlled trials that compared discontinuation vs continuation of RAS inhibitors in patients undergoing non-cardiac and non-vascular surgery.

Five randomized controlled trials (n = 10 773 patients; 5388 randomized to discontinuation) were included. Discontinuation of an RAS inhibitor probaby reduced peri-operative hypotension (27.66% vs 34.06%; risk ratio [RR] 0.81, 95% confidence interval [CI] 0.73-0.89; moderate certainty). The evidence is very uncertain about effects on peri-operative hypertension (9.46% vs 8.05%; RR 1.38, 95% CI 0.66-2.89; very low certainty). For major clinical outcomes, discontinuation suggested little to no difference in acute kidney injury (10.45% vs 10.69%; RR 0.98, 95% CI 0.66-1.45; low certainty), acute heart failure (5.38% vs 5.32%; RR 1.00, 95% CI 0.76-1.31; low certainty), myocardial infarction (1.22% vs 1.00%; RR 1.19, 95% CI 0.60-2.39; low certainty), stroke (0.42% vs 0.40%; RR 1.04, 95% CI 0.56-1.93; low certainty), and arrhythmias (1.80% vs 1.40%; RR 1.28, 95% CI 0.69-2.38; low certainty).

These findings suggest that discontinuation of RAS inhibitors is likely to reduce peri-operative hypotension in patients undergoing non-cardiac, non-vascular surgery, but the evidence is very uncertain about effects on peri-operative hypertension and major clinical outcomes.