An additional therapeutic effect of adequate hyperventilation in severe acute brain trauma: normalization of cerebral glucose uptake.

In a total of 309 frequent serial studies, arteriojugular differences in glucose and oxygen levels were concurrently evaluated in 33 adult patients who were experiencing the most acute phase of severe brain trauma. Hyperventilation therapy was optimized to maintain both normalized intracranial pressure and cerebral extraction of oxygen. Under these circumstances, global cerebral glucose extraction was found to be closest to normal during profound optimized hyperventilation, with PaCO2 levels below 25 mm Hg. In contrast, during normocapnia global cerebral glucose extraction dropped below normal range, indicating impairment of cerebral glucose uptake. Findings from this study show that in severe acute brain injury, optimized hyperventilation exerts an additional metabolic effect with respect to cerebral glucose uptake.