Significance and cost-effectiveness of somatosensory evoked potential monitoring in cervical spine surgery

Abstract

Background : Intraoperative somatosensory evoked potential (SSEP) monitoring during cervical spine surgery is not a universally accepted standard of care. Our retrospective study evaluated the efficacy and cost-effectiveness of intraoperative SSEP in a single surgeon's practice. Materials and Methods : Intraoperative SSEP monitoring was performed on 210 consecutive patients who had cervical spine surgery: anterior cervical approach 140 and posterior approach 70. They were screened for degradation or loss of SSEP data. A cost analysis included annual medical costs for health and human services, durable goods and expendable commodities. Results : Temporary loss of the electrical wave during cauterization resolved upon discontinuation of the cautery. We had no loss of cortical wave with preservation of the popliteal potential. A drop in the amplitude of the cortical wave was observed in three patients. This drop was resolved after hemodynamic stabilization in the first patient, readjusting the bone graft in the second patient, and interrupting the surgery in the third patient. The additional cost for SSEP monitoring was $835 per case and the total cost of the surgery was $13,835 per case. By spending $31,546 per year on SSEP, our institution is saving a total cost ranging from $64,074 to $102,192 per patient injured per year. Conclusion : Intraoperative SSEP monitoring is a reliable and cost-effective method for preventing postoperative neurological deficit by the early detection of vascular or mechanical compromise, and the immediate alteration of the anesthetic or surgical technique.