Delayed bleeding (DB) is the common adverse event after gastric endoscopic submucosal dissection (ESD), and post-ESD electrocoagulation (PEC) is widely performed as a prophylactic hemostasis to prevent DB. On the other hand, we occasionally encounter post-ESD electrocoagulation syndrome (PECS), characterized by abdominal pain, fever without perforation. PECS is expected to be caused by thermal tissue damage and known as a general adverse event in esophagus and colorectal ESD. However, it is also recently reported in gastric ESD cases. To reduce thermal damage, we underwent a non-coagulation clipping (NCC) as a prophylactic hemostasis that is only mechanical clipping to all exposed vessels without electrocoagulation. This study aimed to evaluate the safety and efficacy of NCC compared with conventional PEC, focusing on DB, postoperative inflammatory response, and incidence of PECS.

This retrospective observational study was conducted consecutive patients who underwent gastric ESD at Kyoto Prefectural University of Medicine between January 2023 and March 2025. PEC was performed from January 2023 to March 2024, and NCC from April 2024 to March 2025. Patients with aspiration pneumonia, definitive causes of inflammatory elevation without PECS, complete ulcer closure, or combined use of coagulation and clipping were excluded. Outcomes were the incidence of adverse events including DB and PECS after gastric ESD with PEC or NCC. PECS was defined as abdominal pain and fever with WBC ≥10,000/µL or CRP ≥0.5 mg/dL, without perforation. Statistical analyses were performed using chi-squared test, Fisher’s exact test, Mann–Whitney U test, and Firth’s bias‑reduced estimation, with significance defined as p < 0.05.

Of the 294 patients initially enrolled, 36 were excluded and 126 in the PEC group and 132 in the NCC group were analyzed. Patient backgrounds, comorbidities, lesion characteristics, and use of antithrombotic agents were generally comparable. Endoscopic lesion size (median [IQR]: 10 [6-19] mm vs. 13 [8-21] mm; p = 0.015) and resection size (median [IQR]: 28 [23-36] mm vs. 32 [25-40] mm; p = 0.022) were significantly larger in the NCC group. The median time required for prophylactic hemostasis did not differ significantly between groups (median [IQR]: 11 [9-14] min vs. 12 [9-16] min; p = 0.106). In the NCC group, a median of 15 clips (IQR 12–20) was used. About the postoperative course, abdominal pain occurred significantly less frequently in the NCC group compared with the PEC group (6.1% vs. 13.5%; p = 0.044), and fever incidence was also lower in the NCC group (5.3% vs. 14.3%; p = 0.015). On POD1, WBC was significantly lower in the NCC group (median [IQR]: 8.0 [6.7–9.3]×10⁶/µL vs. 8.8 [7.1–10.0]×10⁶/µL; p = 0.007), whereas CRP and hemoglobin levels showed no significant differences. PECS occurred in 4.8% of PEC patients but in none of the NCC patients (p = 0.013). DB and delayed perforation occurred at similar rates in the PEC and NCC groups (4.0% vs. 3.8%; p = 1.000), (0.8% vs. 0.8%; p = 1.000). In univariate analysis, NCC was significantly associated with reduced PECS incidence (odds ratio [OR] 0.264, 95%CI: 0.023-0.776, p=0.005). These findings suggest that mechanical clipping alone is sufficient for effective prophylactic hemostasis after gastric ESD in many cases and avoiding electrocoagulation on the post ESD ulcer may reduce the occurrence of PECS.

The NCC method significantly reduced incidence of postoperative abdominal pain, fever, inflammatory response, and PECS compared with PEC, without increasing DB. NCC has a potential of a safe, less invasive alternative procedure to PEC. Further studies are required to establish its efficacy.