Incidence of Rebleed Following Cerebrospinal Fluid (CSF) Drainage in Poor Grade Subarachnoid Hemorrhage: An Institutional Experience

Background: The outcome of poor grade subarachnoid hemorrhage (SAH) is dismal. Some of these patients need cerebrospinal fluid (CSF) drainage procedure for the hydrocephalus and intraventricular hemorrhage (IVH) which may precipitate rebleeding. However, aneurysmal rebleed following CSF drainage procedure is controversial.

Objective: Our study aimed at analyzing the effect of CSF drainage procedure on aneurysmal rebleeding.

Material and methods: We retrospectively analyzed the records of all the consecutive patients diagnosed with poor grade aneurysmal SAH over three year period. Patients initially requiring either external ventricular drainage (EVD) or lumbar drain (LD) were included in the study group, and the rest (not requiring drainage) were included in the control group. Rebleeding was confirmed on computed tomography. The factors affecting rebleeding were analyzed.

Results: Overall 194 patients with poor grade SAH were enrolled in the study (91 males: 103 females; mean age: 50.6 years). The study group had 91 patients (83 EVD and 8 LD) while 103 patients were in the control group. Posterior circulation aneurysms, poor grade SAH, hydrocephalus, and IVH were more common in the study group P < 0.001. The rebleeding rate was 7.6% in the study group and 8.7% in the control group. On univariate analysis size >1 cm, multiplicity, multilobularity, vasospasm, and CSF drainage were significant risk factors for rebleeding (P < 0.001). On multivariate analysis aneurysm size >1 cm, CSF overdrainage >250 ml/day were significantly associated with risk of rebleeding.

Conclusion: Ventricular drainage is essential to relieve acute hydrocephalus and drain IVH in SAH and we found no significant association between CSF drainage and rebleeding. However, rapid overdrainage of CSF can lead to aneurysm rupture, hence controlled controlled CSF drainage should be undertaken.