Carprofen increases the risk of anastomotic leakage in a mouse model of Roux-en-Y gastric bypass

Anastomotic leakage following intestinal surgery in a murine Roux-en-Y gastric bypass (RYGB) model is usually fatal. Carprofen, a commonly used non-steroidal anti-inflammatory drug (NSAID) for postoperative analgesia in rodents, has been linked to negative effects on intestinal wound healing. The postoperative use of the non-opioid analgesic metamizole in this setting is rare. Here, we compared the potential effects of carprofen and metamizole on intestinal anastomotic healing in a murine RYGB model in order to optimize perioperative care in this animal model. A total of 38 mice underwent RYGB surgery as part of an in-house surgical training programme and received either carprofen (<i>n</i> = 17) or metamizole (<i>n</i> = 21) postoperatively. Within three postoperative days, anastomotic leakage occurred in 82% of carprofen-treated mice (14 of 17), mainly at the lower jejunal anastomosis (<i>n</i> = 12). The incidence of anastomotic leakage in the metamizole group was remarkably lower, occurring in four of 21 mice (19%) during the same period with three cases at the lower and one at the upper anastomosis. This is the first study demonstrating the detrimental effect of carprofen on jejunal anastomotic healing in a murine RYGB model. These findings underscore the critical importance of selecting appropriate analgesics for intestinal anastomosis surgery.