Cerebral venous flow velocity predicts poor outcome in subarachnoid hemorrhage

Predictors of clinical outcome in aneurysmal subarachnoid hemorrhage (SAH) vary in reliability. Measurement of cerebral venous hemodynamics by transcranial color-coded duplexsonography (TCCS) has become of increasing interest lately, and correlation with intracranial pressure (ICP) seems to be high. The aim of the presented study was to assess changes of cerebral venous hemodynamics in SAH and evaluate its relationship with clinical outcome.

We performed sequential TCCS of venous peak flow velocities (vp-FVs) in the transversal sinus in 28 consecutive patients with aneurysmal SAH (Hunt and Hess scale 1 to 5). Measurement was initiated at onset of arterial vasospasm up to 5 days after SAH. All patients had a continuous ICP monitoring. Clinical outcome was evaluated with the modified ranking scale (MRS) 30 days after SAH. Patients were divided according to outcome: group I good recovery (MRS 0-III) and group II poor outcome (death or MRS IV-V). Maximum vp-FV, time-averaged vp-FV (mv-FV), and ICP were compared between groups.

Vp-FV and mv-FV as well as ICP of group II exceeded values of group I (P<0.001 for all 3 parameters). Vp-FV showed a positive correlation with ICP (r=0.63; P<0.001). A vp-FV exceeding 35.4 cm/s (sensitivity 100%; specificity 90.9%), an mv-FV exceeding 27.3 cm/s (sensitivity 94.1%; specificity 81.8%), and an ICP exceeding 24 mm Hg (sensitivity 87.5%; specificity 81.8%) predicted poor outcome (receiver operating characteristic analysis).

Increased ICP values correlate with increased venous flow velocities. In SAH, increased ICP and increased venous flow velocities are associated with poor outcome. Flow velocity of the transversal sinus is a highly sensitive, reliable, and early predictor of outcome in SAH.