The Utility of Bispectral Index Monitoring in Management of Motor Evoked Potential Depression Occurring During Scoliosis Surgery under Total Intravenous Anesthesia: A Case Report

Motor evoked potential monitoring is becoming one of the gold standard monitoring performed to detect nerve injuries caused by surgical manipulation, especially motor deficits during spine surgeries, but there exist clinical situations that make its interpretation very challenging. Recently, a 19-year-old male who underwent scoliosis correction with total intravenous anesthesia using propofol and remifentanil showed overall motor evoked potential depression on all recording sites during surgery, only to show signal recovery after propofol infusion was stopped. We present the utility of bispectral index monitoring, a processed electroencephalogram monitor that measures the depth of anesthesia, in the situation when motor evoked potential depression occurs without any factors which affect motor evoked potential responses except anesthetic depth.