S Duffy1, P C Reid, F Sharp. 1. University Department of Obstetrics and Gynaecology, Northern General Hospital, Sheffield, UK.
Abstract
OBJECTIVE: To study the effects of electrosurgery on the living human uterus. DESIGN: Prospective observational study. SUBJECTS: Nine women with recurrent refractory dysfunctional uterine bleeding, listed for hysterectomy. INTERVENTION: Experimental endometrial resection on patients immediately prior to hysterectomy. MAIN OUTCOME MEASURES: The influence of power output, duration of exposure and repetition of consecutive surgical applications on the size of the zone of thermal necrosis in uterine tissue. RESULTS: Resection of the endometrium was associated with a narrow zone of thermal necrosis of between 0.69 and 0.76 mm which was not dependent on power output. Duration of exposure, however, was directly related to tissue necrosis (1.44 vs 1.88 mm for 1s and 5s, respectively). Coagulation by pin-point desiccation caused a zone of thermal necrosis of 3.30-3.77 mm that was independent of either power or duration of exposure to electrical energy. Thermal transmission through the uterus in situ, during electrosurgery was minimal, the maximum recorded rise in temperature from the baseline was 0.4 degrees C. The differences between the in vitro and in vivo effects of electrosurgery are highlighted and the possible reasons for these differences explored. CONCLUSIONS: The potential for unwanted thermally-induced damage to the uterus is small.
OBJECTIVE: To study the effects of electrosurgery on the living human uterus. DESIGN: Prospective observational study. SUBJECTS: Nine women with recurrent refractory dysfunctional uterine bleeding, listed for hysterectomy. INTERVENTION: Experimental endometrial resection on patients immediately prior to hysterectomy. MAIN OUTCOME MEASURES: The influence of power output, duration of exposure and repetition of consecutive surgical applications on the size of the zone of thermal necrosis in uterine tissue. RESULTS: Resection of the endometrium was associated with a narrow zone of thermal necrosis of between 0.69 and 0.76 mm which was not dependent on power output. Duration of exposure, however, was directly related to tissue necrosis (1.44 vs 1.88 mm for 1s and 5s, respectively). Coagulation by pin-point desiccation caused a zone of thermal necrosis of 3.30-3.77 mm that was independent of either power or duration of exposure to electrical energy. Thermal transmission through the uterus in situ, during electrosurgery was minimal, the maximum recorded rise in temperature from the baseline was 0.4 degrees C. The differences between the in vitro and in vivo effects of electrosurgery are highlighted and the possible reasons for these differences explored. CONCLUSIONS: The potential for unwanted thermally-induced damage to the uterus is small.