[Value of brain metabolic studies in post-traumatic coma].

In 34 comatose patients in the acute phase, the mean hemispheric CBF is lowered as well as the CMRO2, with a quite good relation between these values and the coma level and prognostic so. The cerebral response to a PaCO2 range indicates a quite good relation with the coma level (the lowest value in the most severe comas). The cerebral autoregulation study, using Aramine induced hypertension, can separate the cases with a present autoregulation and the cases with a loss of autoregulation (the most severe and the poorest prognosis). In dynamic conditions (variation of the PaCO2 or Aramine induced hypertension), the change in CMRO2 is interesting : rather good prognosis among the patients with a normal metabolic autoregulation - poor prognosis among those whose metabolic autoregulation is lost.