[Cerebrospinal fluid dynamics in experimental subarachnoid hemorrhage].

To investigate the acute effects on intracerebral pressure, intracranial reserve capacity and CSF absorption resistance, a subarachnoidal haemorrhage was induced experimentally in a cat by bolus injection or continuous infusion of autologous blood into the cisterna magna. Intracisternal bolus injection resulted in a brief steep increase in intracranial pressure. 30 or 60 minutes after the haemorrhage the median intracranial pressure is slightly increased, the reserve capacity markedly reduced and the CSF absorption resistance considerably enhanced. During intracisternal blood infusion there is a continuous intracerebral pressure rise that persists to the end of the infusion and decrease again within a short time. This intracranial pressure behaviour is due to the simultaneous reduction of intracranial reserve capacity and the increase in CSF absorption resistance during the blood infusion.