Objective: To compare the gross and histologic effects of bipolar and monopolar cautery, ultrasonic scalpel, and CO(2) laser on porcine ureter, bladder, and rectum.
Design: Experimental prospective study.
Setting: Cleveland Clinic Foundation Animal Research Laboratory, Cleveland, Ohio.
Animal(s): Nonpregnant adult female pigs.
Intervention(s): The rectum, bladder, and ureters of 12 female pigs were injured with four different laparoscopic energy sources.
Main outcome measure(s): Gross measurements of injured tissue and histologic analysis of the depth of the tissue injury.
Result(s): Gross assessment results were that monopolar injuries of the bowel and bladder were significantly longer than ultrasonic injuries (P<0.01). Injuries were generally manifest as coagulative denaturation of collagen bundles. This resulted in an eosinophilic homogenization of tissue. Nuclei were retained in the injured tissue, although in most cases they had a pyknotic, streamed appearance. The CO(2) laser caused no deep-tissue injury.
Conclusion(s): Laparoscopic energy sources injure tissue differently. Monopolar cautery appears to have the most lateral spread of thermal energy. The CO(2) laser appears to cause the least deep-tissue injury.