Intracellular acidosis in human and experimental brain injury.

Brain tissue acidosis is considered to play a role in the complex sequence of events following traumatic brain injury. This report reviews the experimental and clinical research conducted at the Medical College of Virginia to help clarify the extent of metabolic derangement that occurs and to evaluate the effect of treatment. Experimental injury models in ventilated animals showed that trauma produces a mild brain tissue acidosis that recovers within hours of injury. Hypoxia combined with trauma produces a relative ischemia and exacerbates the acidosis, which eventually resolves with resuscitation. Other studies revealed that CSF lactate measurements should be interpreted with caution, particularly in patients with subarachnoid hemorrhage. The results of two randomized clinical trials testing therapeutic effects of sustained hyperventilation and treatment with tromethamine (THAM) are discussed.