BIPOLAR COAGULATION AT DIFFERENT ENERGY-LEVELS - EFFECT ON PATENCY

Determining the extent of damage caused by bipolar coagulation at diff erent levels is critical in microsurgery. If no significant damage occ urs at known levels, this technique can be used instead of ligation, s aving considerable time. One hundred eighty Sprague-Dawley rats were d ivided into six groups of 30 each. The effects of bipolar coagulation were assessed at either 2 or 10.4 watts at the junction between the co mmon femoral artery and a branch vessel. Three common clinical setting s were used: branch coagulation without interruption of blood flow in the common femoral artery; branch coagulation with interruption of blo od flow for 30 minutes; and branch coagulation with arterial anastomos is 3-5 mm distal to the branch. Control procedures without coagulation were performed on the contralateral vessels. The animals were re-expl ored at 5-7 days. No differences occurred in patency of the coagulated vessels at 2 or 10.4 watts of delivered energy as compared with contr ols. Recanalization of the side branch occurred in approximately 80% ( 144/180) of specimens. Extensive damage to endothelium, tunica intima, and tunica media occurred for 1-2 mm around the site of the coagulate d branch. The forceps pick-up test demonstrated little difference in f low of the cauterized vessel compared with controls. However, the caut erized vessel had a clinically weaker pulse stream of the transected c ommon femoral artery. Recanalization of the coagulated side branch com monly occured with a fibrin cap at the end of the vessel. Manipulation of the branch vessel frequently caused rebleeding. Our study shows th at bipolar coagulation can be used effectively if coagulation is locat ed at least 2 mm from the main vessel.