Intraoperative monitoring of sensory evoked potentials may be neither a proven nor an indicated technique.

Excluding specific neurosurgical indications for cortical localization or peripheral nerve surgery, the use of sensory evoked potentials as a monitor in the operating room should be controversial at this time. Whether appropriate or not, legal and medical forces have largely established the use of somatosensory evoked potential monitoring as a standard during procedures that threaten the integrity of the spinal cord. The author believes that such monitoring should not replace the use of a "wake-up" test during these procedures because of the recognized possible occurrence of false negative results (i.e., normal evoked potentials despite abnormal spinal cord function). Another apparent established practice is monitoring of brainstem auditory evoked potentials to recognize the onset of disturbance in the auditory system. It has not been established that other recommended evoked potential monitoring practices, such as somatosensory evoked potential monitoring for such purposes as recognizing cerebral ischemia, or brainstem auditory evoked potential monitoring for recognizing untoward medullary stimulation, are as good as or better for these purposes than currently recognized and simpler monitors.