Intraoperative monitoring

Intraoperative monitoring and testing is conducted to improve neurological outcomes from surgery that incurs risk of neurological injury. Many techniques are familiar from the outpatient neurodiagnostic laboratory, and can be applied with minor modifications to the operating room setting. Other techniques are specific to the operating room. Transcranial electrical motor evoked potentials cannot be applied to awake patients, but are commonly used under general anaesthesia. Monitoring teams understand the tactics for obtaining quality recordings and calling alarms when potentials change past preset limits. Surgeons and anaesthesiologists have a variety of tactics for responding to adverse neurodiagnostic changes beginning with easy actions. In experienced hands, intraoperative neurophysiological monitoring substantially reduces post-operative deficits. For example, in spinal cord monitoring the risk of paraplegia and paraparesis is reduced by 60%. Monitoring is carried out by a technologist in the operating room under the supervision of an experienced neurophysiologist. In straightforward cases, the neurophysiologist may remotely monitor from outside the operating room.