OBJECTIVETo evaluate the accuracy and related affecting factors of the intra-operative somatosensory evoked potential monitoring in cervical and thoracic surgery.

METHODSCortical somatosensory evoked potential (CSEP) monitoring and sub cortical somatosensory evoked potential (Sub-CSEP) monitoring were performed in cervical and thoracic surgery. Somatosensory evoked potential (SEP) changes were recorded during anaesthesia and operation and postoperative, which could be used to evaluate accuracy of SEP.

RESULTSBilateral CSEP wave abnormalities were related to anaesthesia, decreasing wave amplitudes did not reach the alarming standard. Intra-operative manipulation to affect spinal cord would influence iso-lateral wave abnormality of CSEP and sub-CSEP, decreasing amplitudes reached the alarming standard. Local hypothermia such as cold water irrigating spinal cord would be to prolong the latent period. Low mean arterial pressure (MAP) mostly influenced amplitudes. Changes of SEP in local hypothermia and MAP did not reach the alarming standard.

CONCLUSIONSCSEP and Sub CSEP can reflex physiopathological condition of spinal cord, it is useful in evaluating spinal cord function and providing the safety for cervical and thoracic surgery.