Electrocardiographic Interference on Bispectral Index Monitor: A Case of Crossed Wires

The Bispectral Index (BIS) has been widely utilized to monitor patients’ levels of consciousness during anesthesia. Despite its practicality and prevalence, BIS monitors have been reported to show erroneous readings due to various factors that interfere with the proper reading of the brain’s electrical activity. We present a case where the BIS monitor misinterpreted the patient’s cardiac activity as her neural activity and resulted in a falsely elevated BIS number despite proper placement and lack of underlying patient medical condition, including neurological injury. It is crucial to remain vigilant about monitoring and understanding BIS readings to assess patients’ awareness and effectiveness of anesthesia properly.