Updated evidence of the effectiveness and safety of transanal drainage tube for the prevention of anastomotic leakage after rectal low anterior resection: a systematic review and meta-analysis.

Backgrounds: Anastomotic leakage (AL) represents a major complication after rectal low anterior resection (LAR). Transanal drainage tube (TDT) placement offers a potential strategy for AL prevention; however, its efficacy and safety remain contentious.

Methods: A systematic review and meta-analysis were used to evaluate the influence of TDT subsequent to LAR as part of the revision of the surgical site infection prevention guidelines of the Japanese Society of Surgical Infectious Diseases (PROSPERO registration; CRD42023476655). We searched each database, and included randomized controlled trials (RCTs) and observational studies (OBSs) comparing TDT and non-TDT outcomes. The main outcome was AL. Data were independently extracted by three authors and random-effects models were implemented.

Results: A total of three RCTs and 18 OBSs were included. RCTs reported no significant difference in AL rate between the TDT and non-TDT groups [relative risk (RR): 0.69, 95% confidence interval (CI) 0.42-1.15]. OBSs reported that TDT reduced AL risk [odds ratio (OR): 0.45, 95% CI 0.31-0.64]. In the subgroup excluding diverting stoma (DS), TDT significantly lowered the AL rate in RCTs (RR: 0.57, 95% CI 0.33-0.99) and OBSs (OR: 0.41, 95% CI 0.27-0.62). Reoperation rates were significantly lower in the TDT without DS groups in both RCTs (RR: 0.26, 95% CI 0.07-0.94) and OBSs (OR: 0.40, 95% CI 0.24-0.66). TDT groups exhibited a higher anastomotic bleeding rate only in RCTs (RR: 4.28, 95% CI 2.14-8.54), while shorter hospital stays were observed in RCTs [standard mean difference (SMD): -0.44, 95% CI -0.65 to -0.23] and OBSs (SMD: -0.54, 95% CI -0.97 to -0.11) compared with the non-TDT group.

Conclusions: A universal TDT placement cannot be recommended for all rectal LAR patients. Some patients may benefit from TDT, such as patients without DS creation. Further investigation is necessary to identify the specific beneficiaries.