The effect of coffee/caffeine on postoperative ileus following elective colorectal surgery: a meta-analysis of randomized controlled trials

Postoperative ileus (POI) is the most common complication of elective colon resection. Coffee or caffeine has been reported to be useful in improving gastrointestinal function after abdominal surgery. This study aimed to investigate the effect of coffee/caffeine on POI in patients undergoing elective colorectal surgery.We searched Cochrane library, Embase, PubMed, and ClinicalTrials.gov (until July 2021) to identify randomized controlled trials (RCTs) evaluating the effect of coffee or caffeine on bowel movements and POI in patients undergoing elective colorectal surgery. The mean difference (MD) for continuous outcomes and risk ratio (RR) for dichotomous outcomes were calculated and are presented with 95% confidence intervals (CIs). A random effects model was used in all meta-analyses.A total of four RCTs including 312 subjects met the inclusion criteria and were included in the meta-analysis. Postoperative coffee or caffeine consumption decreased the time to first bowel movement (MD, - 10.36 h; 95% CI, - 14.61 to - 6.11), shortened the length of hospital stay (MD, - 0.95 days; 95% CI, - 1.57 to - 0.34), and was associated with a decreased risk of the use of any laxatives after the procedure (RR, 0.64; 95% CI, 0.44 to 0.92). The time to first flatus, time to tolerance of solid food, risk of any postoperative complication, postoperative reinsertion of a nasogastric (NG) tube, and anastomotic leakage showed no statistical differences between groups.Postoperative coffee or caffeine consumption improved bowel movement and decreased the duration of hospital stay in patients undergoing elective colorectal surgery. This method is safe and can prevent or treat POI.