Tissue pad degradation of ultrasonic device may enhance thermal injury and impair its sealing performance in liver surgery

Figure 1 Device temperature measurement. A: The harmonic scalpel was applied to the edge of the porcine liver with an almost full tissue bite, and gradually clamped with continuous activation; B: A thermocouple temperature probe was attached to the back side of the passive jaw after every 10 consecutive activations.

Figure 2 Representative trend in device temperature measured after every 10 consecutive activations, until 300 porcine liver dissections were performed. H-HD1000i (blue, solid line) and H-1100 (orange, solid line) are shown. The equations of linear trend line are as follows: H-HD1000i (blue, dot line), y = 0.285x + 69.6; H-1100 (orange, dot line), y = 0.217x + 61.1.

Figure 3  All device temperatures measured in the two independent experiments.

Figure 4 Tissue pad of H-HD1000i and H-1100. A: Before use; B: After 300 repeated activations.