HYPOTHERMIA REDUCES NEUROLOGIC DEFICITS ASSOCIATED WITH PLACEMENT OF A VASCULAR PROSTHESIS IN THE ABDOMINAL-AORTA OF RABBITS

Treatment for atherosclerotic vascular disease in human beings ranges from medical management to interventional therapy, such as angioplasty , atherectomy, and bypass grafting. Recently, bypass grafting with a v ascular prosthesis has received increased attention and clinical use. In the course of studies to optimize use of a small-caliber vascular p rosthesis, five of six rabbits undergoing implantation of a polytetraf luoroethylene vascular prosthesis in the infrarenal abdominal aorta de veloped hind limb neurologic deficits, which resulted from focal ische mic damage to the spinal cord attributable to temporary vascular occlu sion of the abdominal aorta during placement of the vascular prosthesi s. In subsequent studies, induction of systemic hypothermia decreased the rate of development of neurologic deficits from 83 to 9% without a ny apparent perioperative complications associated with decreased body temperature. We determined that mild hypothermia (rectal temperature of 32 to 35 degrees C), combined with aortic occlusion time of <40 min , is sufficient to afford protection from ischemic injury to the spina l cord in the rabbit.