Prevention of Spinal Cord Dysfunction in a New Model of Spinal Cord Ischemia
Document Type
Conference Proceeding
Publication Date
1-1-1995
Description
Paraplegia or paraparesis caused by temporary cross-clamping of the aorta is a devastating sequela in patients after surgery of the thoracoabdominal aorta. No effective clinical method is available to protect the spinal cord from ischemic reperfusion injury. A small animal (rat) model of spinal cord ischemia is established to better understand the pathophysiological events and to evaluate potential treatments. Eighty-one male Sprague-Dawley rats weighing 300 g to 350 g were used for model development (45) and treatment evaluation (36). The heparinized and anesthetized rat was supported by a respirator following tracheostomy. The thoracic aorta was cannulated via the left carotid artery for post-clamping intra-aortic treatment solution administration. After thoracotomy, the aorta was freed and temporarily clamped just distal to the left subclavian artery and just proximal to the diaphragm for different time intervals: 0, 5, 10, 15, 20, 25, 30, 35, and 40 minutes (five animals per group). The motor function of the lower extremities postoperatively showed consistent impairment after 30 minutes clamping (5/5 rats were paralyzed), and this time interval was used for treatment evaluation. For each treatment, six animals per group were used, and direct local intra-aortic infusion of physiologic solution (2 mL) at different temperatures with or without buffer substances was given immediately after double cross-clamp to protect the ischemic spinal cord. Arterial blood (2 mL) was infused in the control group. The data indicate that the addition of HCO3-(20 mM) to the hypothermic (15°C) solution offered complete protection of the spinal cord from ischemic injury. We conclude that this clinically applicable treatment warrants further investigation for the development of a 'neuroplegic solution' for the protection of the ischemic spinal cord during repair of the thoracoabdominal aorta. Additionally, this report describes a technically easy and reproducible model of spinal cord ischemia suitable for evaluating other therapies.
Citation Information
Lopez, S.; Manahan, E.; Evans, J. R.; Kao, R. L.; and Browder, W.. 1995. Prevention of Spinal Cord Dysfunction in a New Model of Spinal Cord Ischemia. American Surgeon. Vol.61(1). 16-20. PMID: 7832375 ISSN: 0003-1348