The Nightknife©: Evaluation of Efficiency and Quality of Bipolar Vessel Sealing

Abstract

Nightknife(©) is a novel reusable bipolar vessel sealing device. In the present study we analyzed its efficiency and quality of vessel sealing in comparison to a standard instrument (LigaSure™). Mesenteric veins and arteries of 5 Swabian-Hall pigs were sealed by means of Nightknife and LigaSure. Thermal performance of both devices was assessed by dynamic thermography. Analysis of the sealed vessels included the determination of seal failure rates and heat-associated macroscopic tissue appearance. The overall sealing rate of Nightknife was significantly higher than that of LigaSure (95.8% versus 87.0%; P=.012). This was associated with a more pronounced thermal spread (8.22±0.13 versus 7.12±0.10 mm; P=.012) and tissue desiccation (2.15±0.06 versus 1.86±0.07; P=.003). Moreover, sealing time (12.30±0.17 versus 7.72±0.17 seconds; P=.038) and tissue temperature (93.73°C±0.69°C versus 66.71°C±2.18°C; P=.001) were significantly higher with the use of Nightknife. Logistic regression analysis revealed that the degree of tissue desiccation correlated with the overall sealing success. Nightknife is as appropriate as LigaSure for the successful sealing of mesenteric vessels despite significant differences in tissue alterations and sealing time between the two devices.