Spinal fluid pyruvate and lactate levels. Relationship to blood gases in goats.

Abstract

WHEN blood gas tensions vary from normal, brain metabolism is also affected. Generally, these alterations are not severe enough to have adverse clinical effects, but in the brain-damaged patient requiring ventilatory assistance, optimum brain metabolism may be necessary for a favorable outcome. Gotoh et al 1 found a reduction in cerebral blood flow during hypocarbia in man and considered the resulting cerebral hypoxia responsible for electroencephalogram slowing in the patients studied. Cain 2 also observed reduced blood flow in dogs during periods of hypocarbia (10 and 20 mm Hg), but oxygenation of the brain appeared adequate based on pyruvate and lactate differences in arterial and jugular venous blood. Alexander et al 3 found increased conversion of brain glucose to lactate during hypocarbia in man. Elevation of pH has been shown to increase glycolysis in cat brain slices with associated increases in pyruvate and lactate production. 4 Results obtained by