Background: This study compared tissue injury produced by 3 types of electrosurgical current (pure cut, coagulation, blend) and two different procedures (snare and "hot biopsy").
Methods: Each type of electrosurgical current was passed through the colon of a live pig by means of a snare or "hot biopsy" forceps, and the depth of tissue injury was determined histologically. The high-frequency electrosurgical current was provided by a single electrosurgical generator. The peak power for each type of current was determined with an oscilloscope.
Results: The depth of tissue injury caused by coagulation current was significantly greater compared with blended current (p=0.0157). The depth of injury with coagulation current also was greater than with pure cut current, (p=0.0461 in a single statistical test; significance removed by Bonferroni-Dunn correction). With the hot biopsy forceps, the depth of tissue injury was deeper compared with that produced with a snare, regardless of the diameter of the snare loop. Peak power at a setting of 30 W was 1154 W for coagulation, 90.2 W for pure cut, and 227.8 W for blend current.
Conclusions: When a high-frequency electrosurgical current device is used, use of a cutting current in the blend mode is recommended instead of coagulation current because this waveform is suitable for incision and provides effective hemostasis. Skillful technique is required for safe use of a hot biopsy forceps, because there is a significant potential for deeper tissue injury with this device.