Management problems in acute hydrocephalus after subarachnoid hemorrhage.

Abstract
In a consecutive series of 473 patients admitted within 72 hours after a subarachnoid hemorrhage, 91 (19%) had hydrocephalus on the initial computed tomogram. Consciousness was unimpaired in 25 of the 91 (28%). In 11 more patients acute hydrocephalus developed within 1 week after subarachnoid hemorrhage. Thirty-eight (8%) of all 473 patients subsequently showed clinical deterioration because of acute hydrocephalus; 11 of these 38 had fluctuations in the level of consciousness. Of the 66 patients with acute hydrocephalus and impaired consciousness on admission, 26 (39%) spontaneously improved within 24 hours. Ventricular drainage was performed in 32 (31%) of the 102 patients with acute hydrocephalus (7% of all 473 patients). Consciousness improved after ventricular drainage in 25 (78%) of the 32 patients. Ventriculitis developed in 12 of the 24 patients with external drainage, mainly after greater than 3 days of drainage, and in none of the eight patients with an internal shunt. Among the 340 patients with aneurysmal subarachnoid hemorrhage and no long-term tranexamic acid treatment, the frequency of rebleeding in patients with ventricular drainage (43% of 23) was significantly higher than in hydrocephalic patients without drainage (15% of 52 patients; chi 2 = 5.009, p = 0.025) and patients without acute hydrocephalus (20% of 265 patients; chi 2 = 5.521, p = 0.019). We conclude that spontaneous improvement occurs in half of the patients with acute hydrocephalus and impaired consciousness on admission, which is usually apparent within 24 hours, and that the outcome of patients who need ventricular drainage will improve if rebleeding and infection after insertion of the ventricular drain can be prevented.