Back to 2011 Program

Introduction: To determine if intraoperative somatosensory evoked potential (SSEP) monitoring could detect and prevent peripheral positioning related neuropathies in high risk urologic patients.
Materials & Methods: 64 patients underwent urethral reconstruction and intraoperative neuromonitoring by a single surgeon from March 2009 through August 2010. Electrodes were placed at the wrist to stimulate peripheral nerves. The SSEPs were recorded at the brachial plexus, cervical spine, and cortex. The functional integrity of the pathway was monitored using the characteristic SSEP waveform parameters (amplitude and latency) from the various recording sites. When significant waveform changes occurred, the patient was re-positioned. Patients were assessed postoperatively for neurologic deficits.
Results: 9 of the 64 patients experienced significant intra-operative SSEP changes. 8 of these SSEP reductions were detected within ten minutes of the beginning of the case and returned to baseline with repositioning of the affected extremity. In these 9 patients, there were no postoperative events. 2 of the 64 patients awoke with neurologic symptoms that were not detected intraoperatively. One experienced transient bilateral forearm numbness and hand extensor weakness. The second patient experienced right upper extremity sensory and motor weakness requiring extensive neurologic assessment and prolonged physical therapy with 95% resolution of symptoms at 3 months.
Conclusions: SSEP is a useful monitoring tool to detect common position related neuropathies. SSEP monitoring may help avoid positioning related neuropathies in high risk patients. Detection of potential peripheral nerve damage largely occurred within the first ten minutes after positioning with resolution after re-positioning and no post-operative events.