Multicentre randomized clinical trial of the effect of chewing gum after abdominal surgery

Background: Postoperative ileus is a common complication of abdominal surgery, leading to patient discomfort, morbidity and prolonged postoperative length of hospital stay (LOS). Previous studies suggested that chewing gum stimulates bowel function after abdominal surgery, but were underpowered to evaluate its effect on LOS and did not include enhanced recovery after surgery (ERAS)-based perioperative care. This study evaluated whether chewing gum after elective abdominal surgery reduces LOS and time to bowel recovery in the setting of ERAS-based perioperative care. Methods: A multicentre RCT was performed of patients over 18 years of age undergoing abdominal surgery in 12 hospitals. Standard postoperative care (control group) was compared with chewing gum three times a day for 30 min in addition to standard postoperative care. Randomization was computer-generated; allocation was concealed. The primary outcome was postoperative LOS. Secondary outcomes were time to bowel recovery and 30-day complications. Results: Between 2011 to 2015, 1000 patients were assigned to chewing gum and 1000 to the control arm. Median LOS did not differ: 7 days in both arms (P = 0.364). Neither was any difference found in time to flatus (24 h in control group versus 23 h with chewing gum; P = 0.873) or time to defaecation (60 versus 52 h respectively; P = 0.562). The rate of 30-day complications was not significantly different either. Conclusion: The addition of chewing gum to an ERAS postoperative care pathway after elective abdominal surgery does not reduce the LOS, time to bowel recovery or the rate of postoperative complications. Registration number: NTR2594 (Netherlands Trial Register).