A novel canine model of spinal cord ischemia with reproducible neurologic outcomes.

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.