RESUMO
In the operation room, members of the surgical team have the ultimate responsibility of safe guarding the patient from electrical devices. The electrosurgical unit is one instrument commonly used during surgical procedures. We have experienced accidental burning. Sixty-seven years-old patient received burn at the site of the ECG electrode which was caused by an electrocautery used in conjunction with electronic monitoring equipment. Although cutting and coagulation powers were very low, the normal size of the ECG electrodes led to the generation of a high current density. Prevention of interactions of this kind between properly functioning monitoring and surgical units requires good communication among all members of the operating room team and every electrical instruments should inspected, tested regularly.