A clinical evaluation of the LOTUS ultrasonic shears in gynaecological surgery

Abstract

A prospective quasiexperimental single blind study was conducted to test the hypothesis that the LOTUS (laparoscopic operation by torsional ultrasound) shears have significant advantage over conventional cutting bipolar forceps when used to divide and coagulate pedicles in gynaecological surgery. Ten university teaching hospital patients between 35 and 51 years of age were recruited. They all underwent elective abdominal hysterectomy and bilateral salpingo-oophorectomy for nonmalignant indications such as fibroids and menorrhagia. The round and infundibulopelvic ligaments were divided with the LOTUS shears or the Power Blade cutting bipolar forceps at open hysterectomy, and the time taken to complete the division was recorded. Two hundred histological samples were examined for thermal damage by the blinded histopathologist. The main outcome measures were the degree of thermal damage on histology, the time taken to divide each structure, and the need for additional haemostasis. Thermal damage was present in 99/200 slides. The LOTUS shears caused thermal damage in 47 sections. The cutting bipolar forceps caused thermal damage in 52 sections. The degree of thermal damage was less with the LOTUS shears. The mean times taken by the LOTUS shears to divide the round ligaments and infundibulopelvic ligaments were 9.24 s and 20.02 s, respectively. The corresponding times for the bipolar forceps were 9.69 s and 27.53 s, respectively. The LOTUS shears were associated with shorter bisection times and less thermal damage in this pilot study. These results were not statistically significant.