Capacitive coupling:
A. Results when energy bleeds from a port sleeve or laparoscope into adjacent (but not touching)To avoid thermal injury to adjacent structures, the laparoscopic field of view must include all uninsulated portions of the electrosurgical electrode. In addition, the integrity of the insulation must be maintained and assured. Capacitive coupling occurs when a plastic trocar insulates the abdominal wall from the current; in turn the current is bled off a metal sleeve or laparoscope into the viscera (Fig. below ). This may result in thermal necrosis and a delayed fecal fistula. Another potential mechanism for unrecognized visceral injury may occur with the direct coupling of current to the laparoscope and adjacent bowel.
Capacitive coupling occu rs as a result of high cu rrent density bleeding from a port sleeve or laparoscope i nto adjacent bowel.