Intraoperative spinal cord monitoring during descending thoracic and thoracoabdominal aneurysm surgery

• Published in: The Annals of thoracic surgery Vol. 74; no. 5; pp. S1873 - S1876
• Main Authors: Dong, Charles C.J, MacDonald, David B, Janusz, Michael T
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY Elsevier Inc 01.11.2002; Elsevier Science
• Subjects: Adult; Aged; Aneurysm, Dissecting - physiopathology; Aneurysm, Dissecting - surgery; Aortic Aneurysm, Abdominal - physiopathology; Aortic Aneurysm, Abdominal - surgery; Aortic Aneurysm, Thoracic - physiopathology; Aortic Aneurysm, Thoracic - surgery; Biological and medical sciences; Evoked Potentials, Motor - physiology; Evoked Potentials, Somatosensory - physiology; Female; Humans; Intraoperative Complications - physiopathology; Intraoperative Complications - prevention & control; Male; Medical sciences; Middle Aged; Monitoring, Intraoperative; Neurologic Examination; Paraplegia - physiopathology; Paraplegia - prevention & control; Postoperative Complications - physiopathology; Postoperative Complications - prevention & control; Predictive Value of Tests; Risk Factors; Spinal Cord - physiopathology; Spinal Cord Ischemia - physiopathology; Spinal Cord Ischemia - prevention & control; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the heart; 26; Spinal cord; Aneurysm; Cardiovascular disease; Arterial disease; Vascular disease; Electrodiagnosis; Ischemia; Surgery; Aorta; Complication; Diagnosis; Somatosensory evoked potential; Human; Nervous system diseases; Treatment efficiency; Exploration; Intraoperative; Medical screening; Treatment; Central nervous system disease; Motor evoked potential; Technique; Spinal cord disease; Aortic disease; Comparative study
• ISSN: 0003-4975; 1552-6259
• DOI: 10.1016/S0003-4975(02)04137-1

Postoperative paraplegia is one of the most dreaded complications after descending thoracic and thoracoabdominal aneurysm surgery. In this study, intraoperative monitoring was applied during resection of descending thoracic and thoracoabdominal aneurysms to detect spinal cord ischemia and help prevent paraplegia. Fifty-six patients (descending thoracic, 25; thoracoabdominal, 31) were monitored intraoperatively with both motor- (MEP) and somatosensory- (SSEP) evoked potentials. MEPs were elicited with transcranial electrical stimulation and recorded from the spinal epidural space (D wave) or peripheral muscles (myogenic MEP). SSEPs were obtained with median and tibial nerve stimulation. A total of 16 patients (28.6%) showed MEP evidence of spinal cord ischemia, only 4 of whom had delayed congruent SSEP changes. In 13 patients (23.2%), ischemic changes in MEPs were reversed by reimplanting segmental arteries or increasing blood flow or blood pressure. None of these 13 patients suffered acute paraplegia regardless of the status of SSEP at the end of the procedure, but 1 of them developed delayed postoperative paraplegia after multisystem failure. Three patients (5.4%) who had persistent loss of MEPs despite of recovery of SSEPs awoke paraplegic. The results demonstrate that compared with SSEP, MEP, especially myogenic MEP, is more sensitive and specific in detection of spinal cord ischemia, and that intraoperative monitoring can indeed help prevent paraplegia.