Comparison of two ultrasonic coagulating shears in sealing pulmonary vessels

Ultrasonic cutting and coagulating devices have been used successfully in thoracic applications such as pulmonary resection or artery harvesting, but few studies have evaluated their use in sealing pulmonary vessels. In this study we compared two commercially available devices, Harmonic Ace+ (HAR, Ethicon Endo-Surgery, Inc., Cincinnati OH, USA) and Sono- Surg (SS, Olympus America, Center Valley, PA, USA), in a canine preclinical model. There were three sections to the study: acute, survival, and ex vivo (burst pressure). Hemostasis of sealed pulmonary arteries and veins was assessed for the initial application and during a simu- lated hypertensive crisis, both immediately after vessel sealing and after a survival period of 30 days. Other intraoperative measures were also evaluated, including transection time, tissue sticking, tissue tags, and char on the seal. Histological evaluation was performed both after initial sealing and after the survival period. Burst pressure of sealed vessels was measured ex vivo. For both devices, hemostasis was excellent, including those measurements made under simulated hypertensive crisis. There were no differences in any of the intraoperative measures or thermal damage evaluated histologically. Wound healing was normal. The burst pressures for ex vivo vessels sealed by HAR (median 619.2 mmHg) were significantly higher than those of SS (350.3 mmHg, P = 0.022). Both devices displayed acceptable characteristics in sealing canine pulmonary arteries and veins. The only difference observed was that HAR produced burst pressures 76.8% greater than SS, which may lead to a lower percentage of failures in the region of physiological interest. Use of ultrasonic devices in thoracic applications provides a high rate of initial hemostasis, supraphysiological burst pressures, and durable seals that heal normally.