RESUMEN
Monopolar electrosurgery is the most commonly used method of dissection and haemostasis in laparoscopic surgery. The problems of active electrode insulation failure, capacitive coupling and direct coupling associated with monopolar electrosurgery can lead to inadvertent and unrecognised energy transfer to tissues outside laparoscopic view and produce serious internal organ damage. The objective of this study was to identify and measure the depth of skin burn around the laparoscopic cannula entry sites, and to determine if the Electroscope Electroshield system can protect against such burns. A prospective randomised study comparing the use of EM-2 Electroscope Electroshield system and conventional electrosurgical instruments in 24 patients who underwent laparoscopic cholecystectomy. The Electroshield system was used in the study group [n = 10] to shield the active electrosurgical electrode throughout the operation. At the end of the operation adequate skin biopsies were taken from the edge of cannula entry wounds at the epigastric and umbilical sites of all patients. The skin biopsies were examined by two independent blinded Pathologists for evidence of coagulative necrosis and the burn depth was measured in mm. Thermal damage of varying depth was identified adjacent to plastic laparoscopic cannulas at both epigastric and umbilical sites in both study groups. There was no significant difference in the burn depth at the epigastric ports [P=0.5896] and at the umbilical ports [P=0.7468] between the two groups [Electroshield used and Electroshield not used]. Within each group there was no statistically significant differences in burn depth between the epigastric and umbilical ports [P=0.2207] for the Electroshield used group, and [P=0.4896] for the Electroshield not used group. The difference in burn depth measurements between the two Pathologists was significant [P=0.0239]. Unrecognised electrosurgical energy transfer can cause skin burns adjacent to plastic cannulas during laparoscopic abdominal surgery at both epigastric and umbilical entry wounds, regardless of whether the EM-2 Electroscope Electrofield system is used or not