Prostacyclin usage for spinal cord protection during experimental thoracic aortic cross-clamping

The risk of paraplegia associated with thoracic aortic cross-clamping is high even when various methods of spinal cord protection are used. In this study prostacyclin I-2 (PGI(2)) was selected as an agent to reduce the spinal cord injury because of its vasodilator, antiaggregant, and cytoprotective properties. Twelve dogs underwent sixty-minute aortic occlusion. Six dogs received PGI(2) whereas the other 6 did not (controls). PGI(2) administration was started at a rate of 5 ng/kg/minute five minutes before aortic occlusion. This dosage was increased to 25 ng/kg/minute during aortic occlusion. PGI(2) at a dosage of 5 ng/kg/minute was maintained for a period of five minutes after the aortic occlusion was released. Three dogs in the control group were paraplegic. There were no paraplegic dogs in the PGI(2) group. Distal aortic perfusion pressure was 31 +/- 6 mmHg in the PGI(2) group and 22 +/- 3 in the control group (P < 0.008). As a result of this study the authors conclude that PGI(2) is a valuable agent for decreasing the risk of spinal cord injury during thoracic aortic cross-clamping lasting sixty minutes.