Paper of the Month - November

Transanal Drainage Tube Use for Preventing Anastomotic Leakage After Laparoscopic Low Anterior Resection in Patients With Rectal Cancer: A Randomized Clinical Trial. JAMA Surg 2021 Oct 6. doi: 10.1001/jamasurg.2021.4568. Online ahead of print.

Song Zhao, MS1; Luyang Zhang, MD2; Feng Gao, MD3; et alMiao Wu, MD4; Jianyong Zheng, MD5; Lian Bai, MD6; Fan Li, MD1; Baohua Liu, MD1; Zehui Pan, MS3; Jian Liu, MD4; Kunli Du, MD5; Xiong Zhou, MD6; Chunxue Li, MD1; Anping Zhang, MD1; Zhizhong Pu, MD7; Yafei Li, MD8; Bo Feng, MD2; Weidong Tong, MD1.

What is known on the subject?

In the East, Transanal Drainage Tubes (TDTs) are used for preventing anastomotic leak (AL) after low anterior resection. TDT is proposed to be beneficial for endoluminal pressure reduction as well as fecal diversion, resulting in a protective effect on anastomotic healing. Several meta-analytical studies have reported that the TDT is effective in AL prevention. This randomized clinical investigated whether AL rate in patients undergoing low anterior resection was reduced by the use of TDTs.

What this study adds

The authors conducted an open label parallel group RCT trial in seven hospitals in China over four years. They included patients who underwent laparoscopic low anterior resection for mid-low rectal cancer. Patients who underwent preoperative chemoradiotherapy, Hartmann’s procedure or intersphincteric resection were excluded. Patients were randomly allocated to two different groups: TDT and non-TDT. If TDT was used, it was placed approximately 5 cm above the anastomosis under laparoscopy at the end of the procedure. The TDT was to be removed at the surgeon’s discretion when the discharge of feces or flatus was clearly and repeatedly observed or when surgeons confirmed the absence of signs of AL, usually at 3 to 7 days after surgery. AL was defined according to the International Study Group of Rectal Cancer description. The primary end point was AL within 30 days after surgery. Secondary end points were the AL grade, anal postoperative pain score, and TDT-related adverse events, such as bleeding and iatrogenic colonic perforations. The study was powered (0.8) to detect a reduction of AL rate from 10.5 to 4.0% and required 560 patients at the 5% significance level.

The study included 560 patients, randomized to two equal groups of 280 patients. The AL rate was 6.4% (n = 18) in the TDT group and 6.8% (n = 19) in the non-TDT group (relative risk, 0.947; 95% CI, 0.508-1.766, P = .87). For patients without a diverting stoma, no significant difference in the AL rate was observed between the TDT group (12 of 208 [5.8%]) and the non-TDT group (15 of 191 [7.9%]; P = .41). A similar result was observed in patients with a diverting stoma (6 of 72 [8.3%] vs 4 of 89 [4.5%]; P = .50).

Further analysis of grades of AL showed no significant difference between the TDT and non-TDT groups (grade B, 14 [5.0%] and grade C, 4 [1.4%] vs grade B, 11 [3.9%] and grade C, 8 [2.9%]; P = .43), regardless of whether there was a diverting stoma. Eight patients (2.9%) were diagnosed with grade-C AL in the non-TDT group, which was twice the rate of the TDT group. However, the difference was not statistically significant, whether the analysis was stratified or not.

Implications for colorectal practice

TCTs confer no benefit in preventing anastomotic leak after laparoscopic low anterior resection.

Report by Audrius Dulskas.

ESCP Affiliates