Should we still use prophylactic drain in gastrectomy for cancer? A systematic review and meta-analysis.

Prophylactic drain in gastrectomy for cancer is still widely used, although some evidence has disputed this practice and spreading enhanced recovery protocol has been pushing towards surgical simplification. This study aimed at assessing the impact of drain placement on important clinical outcomes, evaluating the results of randomised controlled trials (RCTs), or cohort studies whenever information provided by the former was scarce. PubMed, PMC, Cochrane Library, CNKI and Wanfang databases were searched from January 1990 to February 2019, both for RCTs and cohort studies comparing use or avoidance of prophylactic drain in gastric cancer patients undergoing gastrectomy. All RCTs and cohort studies were rated according to Jadad score and Newcastle-Ottawa-Scale, respectively. Meta-analysis was separately performed on RCTs and cohort studies. The following clinical outcomes were considered: anastomotic leak, reoperation rate, additional drain procedure, length of stay, postoperative morbidity, postoperative mortality, readmission rate and drain related complications. Overall, 3 RCTs (330 patients) and 7 cohort studies (2897 patients) were included. Seven studies came from Eastern Countries. Meta-analysis on RCTs evidenced that drain avoidance halves overall morbidity (RR = 0.47, 95%CI 0.26-0.86, p = 0.014) and slightly reduces length of stay (SMD -0.24, 95%CI -0.51-0.03, p = 0.083). Only one postoperative death occurred in the drain group. The other outcomes were either not reported or reported just by one RCT each. Meta-analysis on cohort studies, despite higher statistical power, did not highlight any significant difference. This meta-analysis showed that prophylactic drain avoidance can reduce morbidity and length of stay, while not significantly affecting other major surgical outcomes.