RIPC Shows No Benefit in Noncardiac Surgery

TOPLINE:
The application of remote ischemic preconditioning (RIPC), a noninvasive technique used to induce brief episodes of limb ischemia and reperfusion, did not reduce the rates of postoperative myocardial injury and other complications compared with sham RIPC among patients undergoing high- or intermediate-risk noncardiac surgery.
METHODOLOGY:
Researchers conducted a large, multinational randomized controlled trial (PRINCE) to assess whether RIPC reduces myocardial injury and other complications in high-risk adults undergoing noncardiac surgery.
They included 1213 patients (mean age, 70 years; 60% men) undergoing intermediate- or high-risk noncardiac surgical procedures under general anesthesia across 25 hospitals in eight countries.
The participants were randomly assigned to receive either RIPC or sham RIPC. The RIPC intervention consisted of three 5-minute cycles of ischemia induced by inflating a blood pressure cuff to 200 mm Hg, with each cycle followed by 5 minutes of reperfusion while the cuff was deflated.
The primary outcome was the rate of postoperative myocardial injury, defined by serum cardiac troponin levels exceeding the 99th percentile of the reference limit.
TAKEAWAY:
The occurrence of myocardial injury did not differ significantly between patients in the RIPC group and those in the sham RIPC group (relative risk, 1.02; P = .84).
The number of patients presenting with postoperative troponin values five times above the 99th percentile was not significantly different between the RIPC and sham-RIPC groups.
Additionally, prespecified adverse events did not differ significantly between the groups, except for 30-day hospital readmission rates (6% vs 3.5%), and episodes of limb petechiae (1.7% vs 0.2%), which were significantly more frequent in the RIPC group than in the sham RIPC group.
IN PRACTICE:
'In contrast to previous findings, the PRINCE trial provides robust evidence of the absence of beneficial effects of RIPC on biochemical and clinical outcomes in high- and intermediate-risk noncardiac surgery patients,' the authors wrote.
SOURCE:
The study was led by Massimiliano Greco, MD, of Humanitas University in Pieve Emanuele, Italy. It was published online on June 13, 2025, in Circulation.
LIMITATIONS:
The study did not protocolize anesthesia induction. Preoperative troponin levels were not measured. Additionally, as most participants were from high-income European countries, the findings may have limited generalizability to low- and middle-income settings.
DISCLOSURES:
This study was funded by the Italian Ministry of Health. The authors declared having no conflicts of interest.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.

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