Improved Spinal Cord Perfusion during Thoracoabdominal Aortic Repair[1]

Abstract

Objectives: The study's aim is to evaluate whether intraoperative neurophysiological monitoring with transcranial motor-evoked potentials (tcMEP) permits early recognition of neuronal lesions, thus making interventions to prevent irreversible spinal cord damage possible. Material and Methods: TcMEP monitoring was carried out in twelve patients (mean age 60 years) during open surgical thoracoabdominal aortic replacement. Current approaches for corrective, spinal cord-protecting interventions consist of: raising distal perfusion by increasing cardiopulmonary bypass (CPB) flow, catecholamine application, reducing central venous pressure, reimplantation of segmental arteries, and cerebrospinal fluid (CSF) drainage. Results: Nine patients exhibited loss of tcMEP after segmental aorta clamping. In five patients we observed a recovery of tcMEP through counteractive measures. Three patients died intraoperatively, one patient presented with postoperative paraplegia and loss of tcMEP. Conclusion: TcMEP loss is associated with spinal cord ischaemia, causing postoperative paraplegia. TcMEP monitoring is an excellent method to detect spinal cord ischaemia at an early stage.

Key words

Aortic surgery - thoracoabdominal aortic aneurysm - spinal cord perfusion - transcranial motor-evoked potentials (tcMEP)

1 Presented at the Fourth Joint Meeting of The German, Austrian, and Swiss Society for Thoracic and Cardiovascular Surgery, Hamburg, Germany, February 15 - 18, 2004

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1 Presented at the Fourth Joint Meeting of The German, Austrian, and Swiss Society for Thoracic and Cardiovascular Surgery, Hamburg, Germany, February 15 - 18, 2004