Abstract
Bispectral index (BIS) monitors are useful devices for monitoring the depth of anesthesia. However, reports of contact hypersensitivity caused by electrode placement have been made. Herein, we report a case of a patient who experienced contact dermatitis caused by BIS electrodes.
The patient was a 21-year-old woman who underwent a Le Fort I osteotomy and bilateral sagittal split ramus osteotomy under general anesthesia because of a jaw deformity. Her vital signs during surgery were stable, and she had no abnormalities on the skin of her forehead at the time of the removal of the BIS electrodes after surgery.
Two days after surgery, redness and swelling appeared at the site of the BIS electrode placement. The patient was diagnosed as having contact dermatitis by a dermatologist, and steroid ointment was prescribed. The symptoms improved within 5 days and had disappeared completely at 10 days after the surgery.
Contact dermatitis is a common inflammatory skin disease that can be of two types : irritant and allergic. Previous studies have suggested that propylene glycol, which is a component of the gel used with BIS monitoring electrodes, is a probable cause of contact dermatitis. The erythematous lesions in this case were considered to be delayed-type allergic contact dermatitis because the skin lesions developed relatively slowly.
As BIS monitoring is often used during general anesthesia, cases of allergic contact dermatitis may increase. Therefore, it may be important to follow the condition of the skin for several days after surgery.
