[Hyperventilation and mannitol administration during surgery in patients with space-occupying intracranial lesions]

The aim of this work was to evaluate the effect of hyperventilation and mannitol on brain volume during neurosurgical operations. The material comprises 30 cases of supratentorial tumours. pO2, pCO2, pH and lactate concentration were determined in the arterial blood and in 7 cases also in the CSF. It was established that hyperventilation sometimes fails to decrease ICP; it was observed that hyperventilation was more effective in decreasing brain volume of the pCO2 level decreased by 14,6 mm Hg on the average. The joint use of hyperventilation and hypertonic mannitol was found to be more effective. Neither of the above methods was effective in the case of cystic tumors.