Doppler probe method to reduce delayed bleeding after endoscopic submucosal dissection in the stomach: a propensity-score matched study (with video).

Background: Prophylactic coagulation after gastric endoscopic submucosal dissection (ESD) decreases the rate of delayed bleeding; however, it cannot prevent bleeding completely, and delayed bleeding may occur from non-exposed vessels that were not detected immediately after ESD or where prophylactic coagulation was inadequate. Doppler monitoring systems which can evaluate vascular flow have been recently introduced in the endoscopic field. We developed the Doppler probe method (DOP) using the novel system and conducted a comparative study.

Methods: Data were retrospectively collected at a tertiary hospital between January 2017 and May 2021. Patients who underwent DOP were matched to those who did not (no-DOP, 1:3 ratio). After successful ESD, DOP was performed, and coagulation was additionally performed as necessary. The primary outcome was the rate of 30-day delayed bleeding.

Results: Fifty DOP patients were matched to 151 no-DOP patients. Although the differences were not statistically significant, the DOP group had lower rates of delayed bleeding (2.0% vs. 8.6%, P = 0.11; risk differences, 6.6%; 95% confidence interval [CI] 1.2-12.1%), readmission due to bleeding (0% vs. 2.7%), and blood transfusion (2.0% vs. 3.3%) compared to the no-DOP group. In the whole study population (n = 245), the log-rank test revealed that DOP was correlated to a lower incidence of delayed bleeding (P = 0.036). The Cox regression model revealed a marginally significant effect on delayed bleeding (hazard ratio = 0.17, 95% CI 0.022-1.26, P = 0.082). No procedure-related adverse events were observed.

Conclusion: DOP is safe and may reduce delayed bleeding; however, further prospective studies are required to validate our findings.