Non-Steroidal Anti-Inflammatory Drugs After Abdominal Surgery: An Umbrella Review of Existing Evidence

Background: Multi-modal analgesia is recommended for enhanced recovery after colorectal and abdominal surgery. Previous reviews have reported highly discordant observations around the benefits and risks of non-steroidal anti-inflammatory drugs (NSAIDs). This umbrella review aimed to provide a recommendation based on the best available evidence. Methods: A systematic search was performed for reviews exploring benefits and risks of NSAIDs after abdominal surgery. The quality of reviews was assessed using the AMSTAR-2 tool. Outcomes of interest comprised clinical efficacy (pain, opioid consumption, return of gut function) and safety (intestinal bleeding, anastomotic leak, acute kidney injury). The presence of discordant conclusions across reviews was investigated using the Jadad decision algorithm to determine the best available evidence. Results: Twenty-seven reviews were included, reporting evidence for pain (n=10/27), opioid-consumption (n=11/27), gut function (n=4/27), bleeding (n=1/27), anastomotic leak (n=13/27), and acute kidney injury (n=2/27). The quality of all reviews was ‘critically low’. The reviews were concordant in showing that NSAIDs reduce pain, opioid consumption, and time to gut recovery. Studies reporting anastomotic leak after colorectal surgery were highly discordant. The best available evidence showed an increased risk of anastomotic leak with non-selective NSAIDs, but not convincingly for COX-2 inhibitors. Conclusion: NSAIDs after abdominal surgery reduce pain, opioid consumption, and the time to gut recovery. In the context of colorectal surgery, non-selective NSAIDs may increase the risk of anastomotic leak, but this is based on low quality data. Their use should be limited to selective NSAIDs until robust evidence is available to guide decision-making.