Control of proximal XXXX during aortic cross-clamping: its effect on cerebrospinal fluid dynamics and spinal cord perfusion pressure.

@entity451 @entity101 @entity548 @entity1242 @entity16 @entity1854 @entity2759 @entity439 @entity86 @entity11997 @entity881 @entity432 @entity583 @entity2096 @entity1002
@entity86 remains the most devastating complication of surgery of the descending and thoraco-abdominal aorta. Control of the proximal @entity101 that follows cross-clamping of the thoracic aorta to repain @entity439 of the descending and thoraco-abdominal aorta is necessary to prevent @entity1002 , @entity583 , and @entity548 cerebral events. Both pharmacological and mechanical modalities used to control central @entity101 during @entity432 affect cerebrospinal fluid dynamics and spinal cord perfusion pressure. @entity1854 (doses >5 microg/kg/min), the most widely used pharmacological agent, decreases spinal cord perfusion pressure because it increases cerebrospinal fluid pressure and decreases blood pressure distal to the aortic cross-clamp. This effect cannot be prevented by drainage of cerebrospinal fluid. @entity1242 also decreases spinal cord perfusion pressure, but its effects on cerebrospinal fluid dynamics can be countered by drainage of cerebrospinal fluid. Active distal perfusion with left @entity2096 bypass can provide adequate perfusion of the circulation distal to the aortic cross-clamp while simultaneously reducing cerebrospinal fluid pressure. This approach can maintain mesenteric and spinal cord blood flow, therefore preventing the @entity881 caused by release of cytokines from the splanchnic district and decreasing the incidence of postoperative @entity451 from @entity2759 . In cases of limited retroperfusion, partial exsanguination and cerebrospinal fluid drainage can be used in conjunction with left @entity2096 bypass to prevent rises in cerebrospinal fluid pressure and maintain spinal cord blood flow above the threshold necessary to prevent @entity16 . The use of oxygenated @entity11997 in the subarachnoid space to provide passive oxygenation of the spinal cord during @entity432 remains experimental and requires further investigation.
