Microwave energy compared with heater probe and BICAP in canine models of peptic ulcer hemorrhage

The safety and efficacy of a new endoscopic microwave hemostatic device (Microtaze) was compared with BICAP and heater probe using previously established canine models of endoscopic hemostasis. Parameters evaluated included (a) depth of injury, (b) efficacy of hemostasis (bleeding gastric ulcer model), and (c) strength of coaptive bonding (mesenteric artery model). Depth of injury was graded histologically 1 wk after coagulation as the percentage of lesions showing gastric full-thickness damage for each probe. In depth-of-injury studies probes were applied at maximum force (established endoscopically with a specially designed force gauge) and at maximum power settings (50 W Microtaze, 30 J heater probe, dial setting 10 BICAP) to determine safety. There was no significant difference in the percentage of external muscle layer damage: 85%, 74%, and 86% for Microtaze, heater probe, and BICAP, respectively. Hemostasis was achieved 100% of the time in endoscopically induced bleeding gastric ulcers in heparinized dogs. Canine mesenteric arteries measuring 1-2 mm in diameter were isolated at laparotomy and coaptively sealed, and the bond strength was measured by application of hydrostatic pressure. Bursting pressures were not significantly different for Microtaze, heater probe, or BICAP probes (1062 +/- 77 mmHg, 863 +/- 85 mmHg, and 1154 +/- 139 mmHg, respectively). In conclusion, microwave energy may be applied endoscopically to produce hemostasis with similar safety and efficacy to BICAP and heater probe.