The Annals of thoracic surgery
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Comparative Study
Determination of organ blood flows during retrograde inferior vena caval perfusion.
Cerebral, renal, and hepatic blood flows and oxygen metabolism were measured in 8 mongrel dogs undergoing hypothermic (20 degrees C) retrograde perfusion via the inferior vena cava (IVC) and compared with cardiopulmonary bypass and retrograde superior vena caval perfusion. Inferior vena caval perfusion was performed with aortic drainage and clamping of the superior vena cava at an IVC pressure of 20 or 30 mm Hg. Cerebral, renal, and hepatic blood flows at 30 mm Hg of IVC pressure were 7.5 +/- 3.8, 8.1 +/- 3.1, and 15.3 +/- 5.5 mL.min-1.100 g-1, respectively, as determined by the hydrogen clearance method. ⋯ However, high IVC pressure was associated with high portal venous pressure, which may produce ascites. Regional blood flow during retrograde IVC perfusion was measured by the colored microsphere method in another 8 normothermic dogs. Inferior vena caval perfusion at 30 mm Hg supplied adequate blood flow to the liver (15.44 +/- 12.1 mL.min-1 x 100 g-1) and kidneys (6.35 +/- 2.0 mL.min-1 x 100 g-1).(ABSTRACT TRUNCATED AT 250 WORDS)
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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)