Rapid ischemic preconditioning with a short reperfusion time prevents delayed paraplegia in a rabbit model

Surgery for thoracic and thoracoabdominal aortic aneurysms can be complicated by a significant incidence of neurogenic deficits due to spinal cord ischemia. In this study, we investigated whether ischemic preconditioning (IPC) improves neurologic outcome in a rabbit model.

Forty rabbits underwent infrarenal aortic occlusion. The IPC group (n = 20) had 10 minutes of aortic occlusion to induce spinal cord ischemia, 40 minutes of reperfusion, and 30 minutes of ischemia, whereas the control group (n = 20) had only 30 minutes of ischemia. Tarlov scoring (0, paraplegia; 4, normal) was used to evaluate neurologic functions 7 days later, and spinal cord segments (L4-L6) were stained with hematoxylin and eosin for histologic evaluation.

Complete paraplegia (grade 0) occurred in 15 (75%) of the 20 control animals, whereas in the IPC group, 13 (65%) of 20 animals were completely normal (grade 4) (P < .05).

IPC is beneficial for protecting against neurologic damage after transient aortic occlusion in a rabbit model; however, the protective mechanisms are not clear.