Surgical diathermy is not suitable for vascular tissue welding

The possibility of using radiofrequency energy (RFE) to produce a sutureless anastomosis is attractive both to the military surgeon and on the grounds of cost and simplicity. To investigate this, fresh rabbit aorta was divided lengthways into 4 mm strips and apposed, intima-to-itima. A Valleylab Force 30 Electrosurgery machine supplied RFE at 500 kHz. The energy was applied using standard bipolar forceps and 121 attempts were made to weld the tissue. Seventy seven welds resulted of which 36 were able to withstand a distraction force of greater than 0.1N: the strongest weld was disrupted at 0.35N. Intact tissue withstood a distraction force of greater than 2N, whilst sutured joints disrupted at 0.97 N. It is concluded therefore that radiofrequency energy at 500 kHz does not satisfactorily weld vascular tissue.