Yuji Sugawara1, Hajime Kumagai, Taijiro Sueda. 1. Department of Surgery, Division of Clinical Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, Minami-ku, Hiroshima 734-8551, Japan.
Abstract
PURPOSE: To develop a canine model of spinal cord ischemia (SCI) with highly reproducible neurologic outcomes. METHODS: Spinal cord ischemia was induced by cross-clamping the proximal descending aorta. To produce substantial ischemia in the critical lumbar region, the proximal aortic blood pressure (PAP) was reduced to 80 mmHg by withdrawing blood into a reservoir connected to the left subclavian artery. We conducted an intraischemia spinal cord electrophysiologic study and a postischemia assessment of hindlimb motor function in six animals subjected to this procedure with an aortic occlusion time of 40 min, and in six animals subjected only to aortic occlusion for 60 min. RESULTS: All the animals subjected to this procedure exhibited a significant decrease in motor-evoked spinal cord potentials to transcranial electric stimulation (MEPs) during the acute ischemic phase, and they were paraplegic 48 h after ischemia. In contrast, two of the animals not subjected to PAP reduction showed complete functional recovery with intact MEP findings. CONCLUSION: This model is feasible for experimental SCI studies because it can reliably and easily reproduce substantial ischemia.
PURPOSE: To develop a canine model of spinal cord ischemia (SCI) with highly reproducible neurologic outcomes. METHODS:Spinal cord ischemia was induced by cross-clamping the proximal descending aorta. To produce substantial ischemia in the critical lumbar region, the proximal aortic blood pressure (PAP) was reduced to 80 mmHg by withdrawing blood into a reservoir connected to the left subclavian artery. We conducted an intraischemia spinal cord electrophysiologic study and a postischemia assessment of hindlimb motor function in six animals subjected to this procedure with an aortic occlusion time of 40 min, and in six animals subjected only to aortic occlusion for 60 min. RESULTS: All the animals subjected to this procedure exhibited a significant decrease in motor-evoked spinal cord potentials to transcranial electric stimulation (MEPs) during the acute ischemic phase, and they were paraplegic 48 h after ischemia. In contrast, two of the animals not subjected to PAP reduction showed complete functional recovery with intact MEP findings. CONCLUSION: This model is feasible for experimental SCI studies because it can reliably and easily reproduce substantial ischemia.