Comparison between the effects of electrosurgical coagulation and hot air coagulation on blood vessels.

Hot air coagulation (HAC) was tested directly on small isolated bleeding vessels, in comparison with two conventional methods of electrosurgical haemostasis, to assess haemostasis and histological damage. Eighty rats, divided into nine experimental and one control group, were used to carry out bipolar (BC) and monopolar coagulation (MC) and HAC at three different output powers, on sectioned and bleeding femoral arteries and veins. Haemorrhages were controlled by the minimum time of coagulation necessary to stop them. Four animals in each group were studied immediately after coagulation, and 4 a week after coagulation. Vascular closures induced by HAC were observed to be as safe as electrosurgical closures, and no complications such as secondary haemorrhage were found. The degree of histological damage and postoperative regeneration induced by HAC was more similar to BC than to MC.