[Bispectral Index Electrodes May Induce Skin Lesions]

Bispectral index (BIS) monitoring has been used since the 1990 s, and many studies on BIS monitoring have demonstrated its usefulness and safety. Currently, BIS monitoring has become indispensable for observation of patients under general anesthesia. However, we observed the development of postoperative skin lesions in 13 patients (11 female and 2 male; age range, 14-76 years) resulting from contact with the BIS electrodes between May 2012 and April 2013. None of the patients had a history of allergies or skin diseases prior to surgery. During the surgery, nine patients were placed in the supine position and four in the prone position. The duration of anesthesia ranged from 2 hr 7 min to 13 hr. The overall incidence of skin lesions was approximately 0.27% (13/4,900), and that in patients in the prone position was 3.1% (4/129). The skin lesions resolved within 1 week without scaring following the application of a steroid-containing ointment. Although the occurrence of such skin complications is rare, some patients may experience postoperative anxiety because skin lesions caused by BIS electrodes are noticeable. Therefore, both the usefulness of BIS monitoring and the potential skin complications should be explained to patients preoperatively prior to obtaining patient consent.