ABSTRACT
A series of investigations were undertaken to determine the effects of cardiopulmonary bypass, hypothermia, hyperglycemia, and barbiturates on cerebral high-energy content and intracellular pH, as measured by nuclear magnetic resonance spectroscopy in an adolescent sheep model. The sheep were cooled to 15°C, subjected to one hour of circulatory arrest, which was followed by two hours of reperfusion. Barbiturates may be beneficial because of anticonvulsant and antioxidant properties and because they decrease brain oxygen consumption. Barbiturates have been advocated for cerebroprotection during cardiac surgical procedures. Barbiturates may be beneficial because of anticonvulsant and antioxidant properties and because they decrease brain oxygen consumption. Hypothermia is the mainstay of cerebral protection because it increases ischemic tolerance. Diabetic patients with hyperglycemia who have strokes have a worse outcome than normoglycemic patients. The mechanism postulated for these findings is that hyperglycemia supplies additional substrate for anaerobic metabolism during ischemia.
