Regional cerebral blood flow in the pig after a localized cerebral contusion treated with barbiturates.

Regional cerebral blood flow determined with microsphere technique in anaesthetized pigs was measured before and after a localized cerebral contusion as well as after treatment with pentobarbital. No overall reduction in intracranial pressure or perfusion pressure was observed. Flow reduction due to pentobarbital was different in different regions with a high percentage change in the highly perfused basal structures and cortical grey matter except in the centre of the contusion where the reduction was half compared to the rest of cortical grey matter. Changes in white matter were less than in cortical grey matter but more pronounced than in the very high flow areas (choroid plexus and pineal gland). The accumulated change was greatest in the damaged region. Contralateral to the contusion, where a significant increase in flow was noticed after the contusion, there was a very low accumulated change in flow. In white subcortical matter underlying the contusion a similar low flow change was observed but this was not accompanied by as large an accumulated change as in grey cortical matter. At each fraction of injected pentobarbital a short-lasting increase in intracranial pressure and a reduction in mean arterial blood pressure was observed. The amplitude and the height of the intracranial pressure change was reduced during the pentobarbital injections.