Electrosurgical trocar assembly

摘要

A trocar assembly includes an elongate trocar device and a surrounding cannula. The trocar device incorporates an electrosurgical cutting element which is used to make a guide hole for the cannula and thus enables the remainder of the trocar assembly to enlarge the puncture. An electronic control circuit senses the current flow to the cutting element and, when the trocar device breaks through the wall of the organ being cut, this circuit cuts off the connection to the associated electrosurgical generator. Further control circuitry prevents a surgeon from resuming electrosurgery until a predetermined time period has elapsed. Multiple trocars of different diameters are provided for the same assembly.