Comparing Thermal Damage Using Monopolar Hook Versus Harmonic Scalpel in Total Laparoscopic Hysterectomy; A Double-Blind Randomized Controlled Trial

OBJECTIVE: The use of energy during minimally invasive surgery is associated with thermal damage that can affect the process of wound healing. METHODS: This was a randomized clinical trial including 78 women who underwent total laparoscopic hysterectomy. Patients were randomized based on the device used for colpotomy, monopolar hook versus harmonic scalpel. The thickness of the cauterized margins in the cervicovaginal tissues of the hysterectomy specimens was measured by the pathologist. RESULTS: The primary outcome was the amount of lateral thermal damage based on histologic assessment. Secondary endpoints included postoperative pain scores and postoperative complications. Baseline characteristics were comparable between the two groups. The amount of thermal injury in the monopolar group was significantly greater in only one region, the right lateral order of the cuff (3.85 ± 1.01 mm vs. 3.08 ± 0.95 mm (p = 0.001)). With regard to secondary outcome measures, there was no significant difference between the two groups. CONCLUSION: The use of the harmonic device was associated with significantly less tissue damage during colpotomy in the right lateral cuff region. This is especially important in overweight and obese women in whom the distance between the cervix and the ureter is shorter. Trial Registration https://en.irct.ir/trial/33902?revision=61236. IRCT20180130038567N2.