A study was performed to determine whether alternate site electrosurgical burns could be caused by an inadequately insulated guide wire left in place during endoscopic papillotomy to maintain cannulation of the common bile duct. The safety of four covered guide wires and one standard guide wire was evaluated for electrosurgical safety. All four covered guide wires were coated with polyurethane or polytetrafluoroethylene (Teflon), providing insulation. Leakage currents under normal, limiting case, and fault (damaged insulation) conditions were compared to safety limits. All covered guide wires met safety limits under normal conditions, one of four covered guide wires met safety limits under limiting case conditions, and none met safety limits under fault conditions. The uncovered guide wire did not meet the safety limit under any conditions.
Conclusion: Without a well-insulated guide wire with intact coating, our measurements indicate that leaving a guide wire in place during papillotomy may result in an electrosurgical burn.