A single institution experience using the LigaSure vessel sealing system in video-assisted thoracoscopic surgery for primary spontaneous pneumothorax

This study sought to report our 6-year experience with the LigaSure vessel sealing system（LVSS） in videoassisted thoracoscopic surgery（VATS） for primary spontaneous pneumothorax.A series of 180 consecutive patients with primary spontaneous pneumothorax were operated on in our institution from May 2005 to December 2010.Intraoperatively,large lesions（bullae or blebs） with a diameter more than 2 cm were resected by staplers,and the residual lesions were treated by LVSS.LVSS was also used to ablate the apical area when no lesions were found.Conventional apical pleural abrasion was done in all cases.All patients were successfully treated using VATS with minimal perioperative bleeding.The mean operating time was 76 minutes（range,43-160 minutes） for single-side procedures and 169 minutes（range,135-195 minutes） for bilateral procedures,the mean number of applied staples was 1.93 per patient（range,0-8 days）,the duration of drainage was 3.8 days（range,2-15 days）,and the duration of hospital stay was 5.8 days（range,3-16 days）.Postoperative complications included persistent air leak（〉 5 days） in 11 cases（6.1%） and residual pneumothorax in 6（3.3%）.None required reoperation.The mean duration of follow-up was 57 months（range,24-105 months）.Recurrence was seen in three cases（1.7%）,and all underwent another operation thereafter.None of the lesions in the relapse cases received ablation with LVSS in the first operation.LVSS can optimize VATS for primary spontaneous pneumothorax and reduces the use of single-use staples.The method is safe,easy to use,and cost-effective and produces satisfactory results.

Clinical uses of ligasure vessel sealing system (LVSS) in surgery

This article provides the efficacy of the new device, Ligasure Vessel Sealing System（LVSS） for achieving hemostasis. LVSS is an alternative to suture ligatures, hemoclips, staplers, for ligating vessels and tissue bundles. This new device seals the vessels up to 7 mm in diameter by denaturing collagen and elastin within vessel wall and surrounding connective tissue.

3D TRANSIENT COUPLED THERMOELASTIC-PLASTIC CONTACT SEALING ANALYSIS OF REACTOR PRESSURE VESSEL

Sealing analysis of sealing system in reactor pressure vessels is relevant with multiple nonlinear coupled-field effects, so even large-scale commercial finite element software cannot finish the complicated analysis. A finite element method of 3D transient coupled thermo-elastic-plastic contact sealing analysis for reactor pressure vessels is presented, in which the surface nonlinearity, material nonlinearity, transient heat transfer nonlinearity and multiple coupled effect are taken into account and the sealing equation is coupling solved in iterative procedure. At the same time, a computational analysis program is developed, which is applied in the sealing analysis of experimental reactor pressure vessel, and the numerical results are in good coincidence with the experimental resuits. This program is also successful in analyzing the practical problem in engineering.

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

BACKGROUND 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.AIM To elucidate ultrasonic device tissue pad degradation effects on instrument temperature and sealing performance using ex vivo porcine liver/vessel models.METHODS 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.RESULTS The temperature of the H-HD1000i scalpel was approximately 10℃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℃vs 65.1℃;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).CONCLUSION 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.

A single institution experience using the LigaSure vessel sealing system in laparoscopic nephrectomy

Background Vascular control and tissue dissection are crucial steps in successful laparoscopic surgery. Recently, a new commercially available vessel sealing technology, the LigaSure vessel sealing system （Valleylab, Boulder, USA）,has been introduced. The aim of the present study was to evaluate the benefits of the LigaSure in laparoscopic nephrectomy.Methods From January 2005 to March 2010, 170 laparoscopic nephrectomies were performed with the LigaSure vessel sealing system, including simple and radical nephrectomy and nephroureterectomy. In a retrospective study, the laparoscopic operating time, estimated intraoperative blood loss, duration of postoperative drainage, total amount of postoperative drainage, as well as postoperative hospital stay, were recorded and studied.Results All 170 laparoscopic nephrectomies using LigaSure were accomplished successfully without conversion to open surgery. There was no severe vascular complication or other serious complications. The mean laparoscopic operating time was 124.2 minutes （range, 14-230 minutes）; mean blood loss was 148.6 ml （range, 20-540 ml）; mean time for postoperative drainage was 3.1 days （range, 1-7 days）; mean amount of postoperative drainage was 206.5 ml （range, 27-435 ml） and mean postoperative hospital stay was 6.9 days （range, 3-18 days）.Conclusions Laparoscopic nephrectomy using LigaSure appears technically feasible and easy, and produces satisfactory results. The LigaSure provides a safe and fast way to seal vessels and tissue bundles during nephrectomy.