Avoiding Thermal Injury with Electrocautery

A 2-year-old Labrador retriever underwent surgery to correct a ruptured cranial cruciate injury and died because of complications involving the electrocautery unit. Anesthetic monitoring included an esophageal ECG probe placed above the base of the heart. A monopolar electrosurgery unit (ESU) was used during surgery to control bleeding. Surgery was uneventful and the dog received routine postoperative care. The day after surgery, the dog was dehydrated and had an elevated heart rate (150 beats/min). The dog initially responded to fluid administration, but respiratory distress later developed and the dog continued to deteriorate. Imaging revealed bilateral pleural effusion; thoracentesis revealed a septic exudate. A contrast esophagram revealed an esophageal perforation, but the dog died before surgery could correct the defect. Among the necropsy findings were two linear transmural perforations of the esophagus just dorsal to the heart. Histologic examination of tissue from this area was consistent with a full-thickness thermal injury. An alternative current pathway injury from the ESU to the esophageal ECG monitor probe was suspected as the cause of the esophageal necrosis and perforation and subsequent death. An investigation of the ESU, ECG monitoring device, surgical procedures,grounding pads, coupling gels, and ground plates for the ESU and ECG monitoring devices revealed several possible contributing factors to the incident. Corrective measures included avoiding the use of rectal or esophageal probes when using electrosurgery, moving the ESU from beneath the surgical table to eliminate fluid contact with the unit and prevent further corrosion, and replacing the ESU handpieces with ones that could detect alternative pathway currents.

Commentary: The authors describe an unusual case of esophageal burns in a Labrador retriever secondary to use of an esophageal ECG probe and monopolar ESU. An alternative current pathway between the esophageal ECG probe and the monopolar ESU caused full-thickness burns to the esophagus and resulted in the dog’s death. The authors describe a method for handling such incidents and detail how to avoid such a situation.—Lindsey Snyder, DVM, MS, Diplomate ACVA

An alternative pathway electrosurgical unit injury in a dog. Burgess RCF, Freeman LJ, Jennings RN, Lenz SD. VET SURG 40:509-514, 2011.