Excessive opioid prescribing after surgery can lead to adverse events and exacerbate the opioid crisis. Patients undergoing outpatient breast surgery are often prescribed opioids to manage pain at home; however, the value of this approach is uncertain. The Postoperative Analgesia Intervention with Non-opioid Alternatives (PAIN Alt) trial will address the following research question: among patients undergoing outpatient breast surgery, does opioid-free analgesia (OFA) result in non-inferior 7-day pain intensity and pain interference in comparison to opioid analgesia (OA)?

This is a parallel, assessor-blind, open-label randomised trial conducted at seven university-affiliated hospitals in Canada. A sample of 540 adult patients (>18 years) undergoing outpatient mastectomy or lumpectomy will be included. Participants are allocated 1:1 to receive OA (around-the-clock non-opioids and opioids for breakthrough pain) or OFA (around-the-clock non-opioids, with adjustment of non-opioid drugs and/or non-pharmacological interventions for breakthrough pain). The co-primary outcomes are 7-day pain intensity and pain interference (measured using the Brief Pain Inventory). Secondary outcomes include adverse drug events, physical and mental health status, satisfaction with pain management, postoperative complications, chronic pain, opioid misuse, persistent opioid use, healthcare utilisation and costs. The primary statistical analyses will follow the intention-to-treat principle and be conducted using mixed-effects modelling.

This trial is coordinated by the McGill University Health Centre (ethics approval MP-37-2024-102530), with ethics approval being sought at all participating sites. Our results will be published in an open-access, peer-reviewed journal, presented at relevant conferences and disseminated to the public through press releases.

NCT06507345.

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).