Simultaneous use of two monopolar generators There are occasions in which it is desirable to have two generators in use on the same patient. Coronary bypass procedures commonly have two generators in use, one for surgeon removing saphenous veins from the legs, the second for the other surgeon performing the thoracotomy

The two generators are not synchronised and therefore there are periods when one patient plate has a high positive voltage, whilst the other has a negative voltage. If the generators are isolated, there will be a large potential difference between the patient plates and current will flow from one plate to the other. This is harmless providing there are no sparks or high current densities on the patient's body. To ensure that problems are not experienced, each plate should be placed as near to the appropriate operative site as possible and that the two plates are not allowed to touch, i.e. in coronary bypass procedures, the plate will be placed under the buttocks (for the vein removal team) and under the shoulder (for thoracic surgery team).