Issues surrounding spinal cord protection.

In summary, paraplegia following procedures on the thoracic and thoraco-abdominal aorta is an unpredictable and dreadful complication of multifactorial origin. However, it appears that the major causes of immediate post-operative paraplegia are the depth and duration of ischemia during the period of aortic cross-clamping and failure to identify and reimplant critical vessels that supply blood to the spinal cord. Delayed paraplegia, which has been reported to occur from 1 to 21 days after surgery, is most commonly caused by postoperative hypotension. We believe that the final approach to the prevention of paraplegia following procedures on the thoracic aorta will be one that involves the use of a technique to assure oxygenation of the spinal cord during aortic cross-clamping, through an alternate vascular tree, along with a method that can uniformly depict critical vessels that must be reimplanted at the time of surgery.