Selective deep hypothermia of the spinal cord prevents paraplegia after aortic cross-clamping in the dog model.

We tested, in the dog, the hypothesis that selective deep hypothermia (19 degrees to 12 degrees C) of the spinal cord protects it from the ischemia that follows double aortic cross-clamping. The extracorporal perfusion system consisted of heat exchanger and a pump, infusing saline solution at 5 degrees C into the subarachnoid space (L-6) and draining it through the cisterna magna. After 30 minutes this system cools a normally perfused spinal cord to a stable temperature gradient of 13 degrees C (inflow) to 18 degrees C (outflow).