In moderate to high-risk surgical procedures, 15–25% of patients develop a postoperative surgical site infection. Intraoperative incisional wound irrigation has the potential to reduce surgical site infections, and additional randomised controlled trials are required to provide evidence of effectiveness.

This protocol describes a pragmatic, adaptive, participant and adjudicator-blinded trial at 13 sites in Canada in up to 2500 participants. Participants planned for surgery with an abdominal or groin incision, who are eligible and provide verbal consent through an integrated consent model, are randomised to receive intraoperative incisional wound irrigation with povidone-iodine, saline or no irrigation. The primary outcome is surgical site infection within 30 days postoperatively. Secondary outcomes include quality of life measured 30 days postoperatively and morbidity, mortality and healthcare utilisation within 90 days postoperatively.

This trial has been approved by the research ethics board at the participating centres and stopped enrolling participants on May 23, 2025. All participants will provide verbal consent. Results will be disseminated via presentation at conferences, publication and posted on clinicaltrials.gov.

The study is registered with http://clinicaltrial.gov (NCT04548661; 14 September 2020).