Published online Jul 27, 2022. doi: 10.4254/wjh.v14.i7.1357
Peer-review started: March 11, 2022
First decision: April 8, 2022
Revised: April 12, 2022
Accepted: July 6, 2022
Article in press: July 6, 2022
Published online: July 27, 2022
Processing time: 137 Days and 13.3 Hours
Ultrasonic devices are widely used in many surgical fields, including hepatectomy; however, the negative effects of tissue pad degradation of ultrasonic devices, including those in liver surgery, remain unknown. The Harmonic® 1100 (H-1100) scalpel has advanced heat control technology than previous models, such as the Harmonic® HD1000i (H-HD1000i). We hypothesized that, because of its advanced temperature-control technology, the H-1100 scalpel would show less tissue pad degradation, resulting in superior sealing performance, compared to that with the H-HD1000i scalpel.
To elucidate ultrasonic device tissue pad degradation effects on instrument temperature and sealing performance using ex vivo porcine liver/vessel models.
Two different harmonic scalpels were used and compared: A newer model, the H-1100 scalpel, and an older model, the H-HD1000i scalpel. Using ex vivo porcine livers, each instrument was activated until the liver parenchyma was dissected. The device temperature (passive jaw temperature) was measured after every 10 consecutive activations, until 300 transections of the porcine liver were performed. Tissue pad degradation was evaluated after 300 activations. Sealing performance was evaluated using excised porcine carotid vessels; vessel sealing speed and frequency of vessel burst pressure below 700 mmHg were determined after 300 transections of porcine liver parenchyma.
The temperature of the H-HD1000i scalpel was approximately 10°C higher than that of the H-1100 scalpel, and gradually increased as the number of activations increased. The median passive jaw temperature of the H-HD1000i scalpel was significantly higher than that of the H-1100 scalpel (73.4°C vs 65.1°C; P < 0.001). After 300 transections of porcine liver parenchyma, less tissue pad degradation was observed with the H-1100 scalpel than with the H-HD1000i scalpel (0.08 mm vs 0.51 mm). The H-1100 scalpel demonstrated faster vessel-sealing speed (4.9 sec. vs 5.1 sec.) and less frequent vessel burst pressure < 700 mmHg (0% vs 40%) after 300 activations than the H-HD1000i scalpel; however, the difference did not reach statistical significance (P = 0.21 and P = 0.09, respectively).
In an ex vivo porcine hepatectomy model, the H-1100 scalpel shows lower passive jaw temperature and maintains its sealing performance by avoiding tissue pad degradation compared to that with the H-HD1000i.
Core Tip: The present study showed that the tissue pad of the Harmonic® 1100 (H-1100) ultrasonic scalpel, with improved heat control technology, was preserved even in a hepatectomy model, which is a severe condition for ultrasonic devices. It can be inferred that by using the H-1100 scalpel, even surgeons-in-training inexperienced in handling ultrasonic devices do not need to worry about device issues related to tissue pad degradation. Furthermore, use of the H-1100 scalpel may eventually reduce hospital costs.