Evoked Response Monitoring

Monitoring of the central nervous system using evoked responses allows assessment of neural tracts that are normally silent during coma or anesthesia. This chapter will discuss the techniques of the auditory brainstem response (ABR), somatosensory evoked potential (SSEP), motor evoked potential (MEP), electromyography (EMG), and a few related techniques. These have been applied widely in a large number of surgical and neuroradiological procedures involving head, spine, neck, and vascular procedures among others and are a standard of care in selected procedures. The implications for anesthesia management will be mentioned, as the anesthesiologist plays a key role in facilitating the monitoring.