The Annals of thoracic surgery
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Brain protection during cardiopulmonary bypass and hypothermic circulatory arrest is incomplete. Activation of blood protease cascades may contribute to cellular injury under these conditions. To test this hypothesis, effects of the protease inhibitor aprotinin on recovery of brain energy metabolism after hypothermic circulatory arrest were studied in the piglet. ⋯ The response to endothelium-independent vasodilation (nitroglycerin) was the same in both groups. Carotid blood flow tended to be greater at 20 minutes of reperfusion and less during 45 to 80 minutes after reperfusion in the aprotinin-treated animals. Brain water content postoperatively was 0.8077 in the aprotinin group and 0.8122 in control animals (p = 0.06).(ABSTRACT TRUNCATED AT 250 WORDS)
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Removal of cerebrospinal fluid (CSF) has been proposed as a means of protecting the spinal cord against ischemic injury during thoracoabdominal aneurysm operations. We investigated the effect of altering CSF pressure (CSFP) on lumbar spinal cord blood flow (SCBF) in an experiment using dogs. The SCBF was measured before and after withdrawal of CSF in settings with and without thoracic aortic clamping. ⋯ Elevation of CSFP significantly reduced SCBF. Elevation of CSFP reduces SCBF, but lowering CSFP per se does not increase SCBF whether the thoracic aorta is occluded or not. This supports the notion that removal of CSF offers spinal cord protection only when CSFP is abnormally elevated.