Randomized clinical trial of postoperative chewing gum versus standard care after colorectal resection

Background: Chewing gum may stimulate gastrointestinal motility with beneficial effects on postoperative ileus suggested in small studies. The primary aim of this trial was to determine whether chewing gum reduces length of hospital stay (LOS) after colorectal resection. Secondary aims included examining bowel habit symptoms, complications and healthcare costs.

Method: This clinical trial randomly allocated postoperative patients to standard care with or without chewing gum (sugar-free gum for at least ten minutes, four times/day on days 1-5) in 5 UK hospitals. The primary outcome was LOS. Cox regression was used to calculate hazard ratios (HR) for LOS. Differences between groups for the selected secondary outcomes were assessed using Student’s t-test, χ² and Mann-Whitney tests as appropriate.

Results: Data from 402 of 412 patients, of whom 199 (49.5%) were allocated to chewing gum, were available for analysis. 40% of patients in both groups had laparoscopic surgery, and all study sites used enhanced recovery after surgery programmes. Median (IQR) LOS was not different between groups with both 7 (5-11) days (p=0.962) showing a HR for gum at 0.94 (95% CI=0.77-1.15, p=0.557). Compared to controls, participants allocated to gum had worse quality of life (EQ-5D-3L) at 6 and 12 weeks post-operation (but not day 4), and more Dindo-Demartines-Clavien complications graded 3 and above and deaths (6 vs. 16 and 0 vs. 11, respectively, but none were classed as related to gum). No other differences were observed.

Conclusion: Chewing gum did not alter the return of bowel function or LOS.

Trial registration: ISRCTN55784442