ACUTE HYDROCEPHALUS FOLLOWING ANEURYSMAL SUBARACHNOID HEMORRHAGE

Background: Acute hydrocephalus is a potentially treatable cause of ea rly neurological deterioration after aneurysmal mal subarachnoid hemor rhage (SAH). Methods: A retrospective study of 105 consecutive cases o f aneurysmal SAH was undertaken to determine those factors significant ly related to the development of acute hydrocephalus. Acute hydrocepha lus was diagnosed when the bicaudate index was greater than the 95(th) percentile for age on a CT scan within 72 hours of the ictus, Results : Thirty-one percent of the patients developed acute hydrocephalus. Gr ade of SAH was a significant factor for the development of acute hydro cephalus on univariate analysis as 87% of patients with acute hydrocep halus (29/32) presented with at least grade 3 (Hunt-Hess) SAH (p < 0.0 5). In addition, posterior circulation aneurysms on univariate analysi s were associated with acute hydrocephalus (p < 0.05). Both premorbid hypertension and intraventricular blood (p < 0.05) were predictors for acute hydrocephalus, whereas intracisternal blood, age and sex were n ot. On multivariate linear regression analysis, factors found to be si gnificantly associated with acute hydrocephalus were premorbid hyperte nsion, intraventricular blood, CSF diversion and definitive shunt proc edures. External ventricular drainage was not associated with any inst ances of rebleeding. Thirty-seven percent (10/27) of patients with acu te hydrocephalus who survived were improved by pre-operative external ventricular drainage. Conclusions: Patients with acute hydrocephalus f ollowing SAH can be safely treated with external ventricular drainage. Multiple factors can be identified to predict those patients who will develop acute hydrocephalus post aneurysmal rupture. Approximately 30 % of those patients with acute hydrocephalus will require definitive s hunt placement. Acute hydrocephalus occurred in 31% of aneurysmal SAH patients in this series.