Intracranial hypertension in patients with ruptured intracranial aneurysm

Abstract
Simultaneous continuous recording of intracranial pressure (ICP) and systemic blood pressure was carried out in 26 patients admitted within 1 wk after subarachnoid hemorrhage (SAH) due to a ruptured intracranial aneurysm. The patients were graded as described by Hunt and Hess. Recordings were made for 1-5 days. The more impaired the consciousness, the higher the rate of ICP. In Grade III, IV and V patients, the mean ICP level was in the range of 15-40 mm Hg, 30-75 mm Hg and exceeded 75 mm Hg, respectively. A definite correlation between vasospasm shown by cerebral arteriogram and the clinical grade was not observed. In this series of ICP recordings, a typical plateau wave was never observed. The variations of ICP seen in Grade III and IV patients were the B- and C-waves (15-45 mm Hg in amplitude) described by Lundberg, and those in Grade V patients were the high amplitude monotonous waves synchronous with the arterial pulses (15-40 mm Hg in amplitude). These phenomena may indicate that Grade III and IV patients with SAH are in a condition of cerebral vasomotor instability, and Grade V patients have cerebral vasomotor paralysis.