Effects and safety of neostigmine for postoperative recovery of gastrointestinal function: a systematic review and meta-analysis.

BACKGROUND The purpose of this study was to evaluate the clinical effects and safety of neostigmine for the postoperative recovery of gastrointestinal function. METHODS We performed a literature search of multiple databases [PubMed, Web of Science, Cochrane Library and China National Knowledge Internet (CNKI)] to retrieve studies comparing the postoperative gastrointestinal function of neostigmine and control groups. Review Manager 5.2 was applied for the analysis of heterogeneity, sensitivity, and bias. RESULTS After screening the articles, 17 trials involving 1,589 postoperative patients that met the eligibility criteria were included. The results suggested that neostigmine improved the first passage of flatus [standard mean difference (SMD) =-3.00; 95% confidence interval (CI): (-4.03, -1.97); P<0.001), first defecation [SMD =-3.75; 95% CI: (-5.25, -2.24); P<0.001], time of bowel sound recovery [SMD =-3.42; 95% CI: (-4.49, -2.36), P<0.001], and gastrointestinal function recovery [risk ratio (RR) =1.84; 95% CI: (1.19, 2.86); P=0.007]. Compared to the control group, the neostigmine group had lower rates of abdominal distention [RR =0.39; 95% CI: (0.18, 0.87); P=0.02; I2=76%] and overall adverse events [RR =0.49; 95% CI: (0.29, 0.82); P=0.007]. However, two groups had no difference in postoperative nausea and vomiting (PONV) [RR =0.50; 95% CI: (0.21, 1.23); P=0.13], and respiratory complications [RR =0.96; 95% CI: (0.20, 4.53); P=0.96]. Sensitivity and publication bias analyses showed that these results were robust and exhibited little publication bias. DISCUSSION Small doses of neostigmine may promote the recovery of postoperative gastrointestinal function without obvious side effects.