Treatment of Bleeding Canine Duodenal and Esophageal Ulcers with Argon Laser and Bipolar Electrocoagulation

Abstract

Although electrocoagulation and lasers are used by some endoscopists for control of bleeding from esophageal and duodenal lesions, no one has reported experimental or clinical comparative studies of efficacy or safety in either organ with power outputs and techniques that are used clinically. Our purpose was to compare the efficacy and histologic injury of bipolar electrocoagulation (BPEC) and argon laser photocoagulation (ALP) in the treatment of bleeding standard esophageal (EU) and duodenal ulcers (DU) in dogs. Clinically applied power output and techniques were used in these studies. After duodenotomy or esophagotomy, and heparinization, a standard ulcer maker was used to create acute ulcers to similar size, depth, and bleeding rate. Ulcers were randomly assigned to control or treatment with ALP or BPEG. Hemostatic effectiveness was determined acutely, and histologic injury was assessed after 7 days. Standard DUs were more difficult to treat than esophageal ulcers because of higher bleeding rates and less retraction of the submucosa with coagulation. BPEC and high-power ALP (6 or 10 W) had comparable efficacy in the duodenum although ALP caused more tissue injury. Standard EUs were easy to treat with either BPEC or ALP. For EU, high-power ALP (8-10 W) resulted in more tissue injury than BPEC or control. The mean duodena1 wall thickness of adult mongrel dogs was not significantly different from thickness of the esophagus (by micrometer, 2.52 ± 0.04 vs. 2.52 ± 0.05 mm or by histologic measurement 2.41 ± 0.05 vs. 2.76 ± 0.08 mm). The histologic injury seen with high-power ALP treatment in the esophagus or duodenum in this study was significantly greater than for the stomach of canines in previously reported studies. Histologic injury with BPEC was not significantly different. Why the duodenum, esophagus, and stomach respond differently to these thermal coagulation methods is uncertain. Both BPEC and lower-power ALP were effective and caused limited tissue damage in the esophagus and duodenum in this study. In our opinion, both should be considered for controlled human trials of endoscopic hemostatasis in the upper gastrointestinal (UGI) tract.