Effect of gum chewing on ameliorating ileus following colorectal surgery: A meta-analysis of 18 randomized controlled trials

Background and objective: Chewing gum, as an alternative to sham feeding, had been shown to hasten the recovery of gut function following abdominal surgery. However, conclusions remained contradictory. We sought to conduct an updated meta-analysis to evaluate the efficacy of gum chewing in alleviating ileus following colorectal surgery. Methods: We searched PubMed, EMBASE, and Cochrane Library Databases through February 2017 to identify randomized controlled trials (RCTs) evaluating the efficacy of the additional use of chewing gum following colorectal surgery. After screening for inclusion, data extraction, and quality assessment, meta-analysis was conducted by the Review Manager 5.3 software. The outcomes of interest were the time to first flatus, time to first bowel movement, length of hospital stay, and some clinically relevant parameters. We also performed subgroup analyses according to the type of surgical approaches or on trials that adopted enhanced recovery after surgery (ERAS) protocol or sugared gum. Results: A total of 18 RCTs, involving 1736 patients, were included. Compared with standardized postoperative care, Chewing gum resulted in a shorter passage to first flatus [WMD = -8.81, 95% CI: (-13.45, -4.17), P = 0.0002], earlier recovery of bowel movement [WMD = -16.43, 95% CI: (-22.68, -10.19), P < 0.00001], and a reduction in length of hospital stay [WMD = -0.89, 95% CI: (-1.72, -0.07), P = 0.03]. Chewing gum was also associated with a lower risk of postoperative ileus [OR = 0.41, 95% CI: (0.23, 0.73), P = 0.003]. No evidence of significant advantages in overall postoperative complication, nausea, vomiting, bloating, readmission and reoperation towards the addition of chewing gum was observed. Subgroup analyses all favored gum chewing. However, the findings are hampered by the significant heterogeneity between trials. Conclusions: Based on current evidence, chewing gum offers an inexpensive, well-tolerated, safe and effective method to ameliorate ileus following colorectal surgery. However, tightly controlled, randomized and considerably larger multicenter trials are warranted to further validate our findings. (C) 2017 Published by Elsevier Ltd on behalf of IJS Publishing Group Ltd.