Water cooling to prevent electrocoagulation syndrome after endoscopic resection of colorectal neoplasm

Background: With the increasing frequency of electrocoagulation hemostasis used in endoscopic submucosal dissection (ESD), the incidence of postoperative bleeding is gradually decreasing, while the incidence of post-ESD electrocoagulation syndrome (PECS) is gradually increasing. Water cooling can reduce thermal injury to the intestinal wall after electrocoagulation. Therefore, this study intends to conduct a prospective, multi-center randomized controlled trial to explore the effectiveness of water cooling after electrocoagulation in reducing the occurrence of PECS. Methods: From November 2022 to October 2023, 420 patients were prospectively included. The patients were 1:1 randomly divided into two groups, named the standard ESD (S-ESD) group and the water-cooled ESD (W-ESD) group. The main outcome measure was the incidence of PECS. Secondary outcomes were ESD operative time, complete resection rates, and adverse effects. Results: The incidence of PECS in the W-ESD group was significantly lower than that in the S-ESD group (7.6% vs. 17.1%, P = 0.003). The median operation time was also shorter in the W-ESD group than in the S-ESD group (37.0 minutes, IQR: 30.0-47.0 minutes vs 42.5 minutes, IQR: 33.0-60.0 minutes, P < 0.001). There was no significant difference in specimen size between the two groups (3.8cm 2 , IQR: 3.1-6.3cm 2 vs 4.6cm 2 , IQR: 3.1-7.1cm 2 , P = 0.286), and the complete resection rate was 100%. No perforation occurred in any patient. Conclusion: Water-cooled ESD technology can significantly reduce the occurrence of PECS.