Intracranial pressure in patients with diffuse cerebral arterial spasm following ruptured intracranial aneurysms.

Intracranial pressure (ICP) was recorded continuously in 12 pre-operative patients with angiographic evidence of diffuse cerebral arterial spasm due to a ruptured intracranial aneurysm. Recordings were made for 1 to 7 days, starting within 13 days after the haemorrhage. 1. An increased ICP was observed in the first week after subarachnoid haemorrhage (SAH) in 4 of the patients without any signs of angiographic arterial spasm. 2. This initial increase was regularly followed by a depression of ICP in between 7--12 days after SAH. In 11 out of 12 patients such a depression was concomitant with the beginning of arterial spasm. During the period of depressed ICP pattern, 6 patients showed little or no neurological deterioration, whereas 5 patients showed impaired consciousness or neurological deficits. 3. A secondary rise of ICP thereafter always followed due to ischaemic brain swelling or infarction, and was usually associated with a serious neurological deterioration. 4. Continuous ventricular drainage was performed to control the secondary increased ICP in 7 patients who survived, 4 of them with good clinical improvement and 3 with severe neurological deficits. 5. In the stage of depressed ICP, the administration of isoproterenol and steroids is recommended in order to try to alleviate the secondary rise of ICP.