Effect of increased intracranial pressure on cerebral vasospasm in SAH.

INTRODUCTION Increased ICP is common and might precipitate cerebral vasospasm (VSP)-induced ischemic events in aneurysmal SAH (ASAH).Our objective was to determine if there is an association between increased ICP and transcranial colour coded Doppler-angiographic VSP (TCCD-A VSP) in relation to delayed neurological deficit (DND) and poor outcome. METHODS A retrospective study was undertaken in 30 patients who were status-post clipping of a ruptured anterior circulation aneurysm causing subarachnoid hemorrhage. ICP monitoring, post-operative MCA/A1 flow velocity measurements, and post-operative angiography were evaluated, with clinical follow up for at least 3 months. Statistical testing was done using a Chi- square analysis between ICP > = 30 mmHg, CPP < = 70 mmHg, TCCD-A VSP and DND and poor outcome. FINDINGS Mean ICP was 34.2 mmHg and mean CPP was 71.3 mmHg. ICP > = 30 mmHg occurred in 56.7%. of patients and CPP < = 70 mmHg occurred in 36.7%. TCCD-A VSP, DND and poor outcome occurred in 56.7%, 60% and 33% of patients respectively. Overall ICP > = 30 mmHg was significantly related to TCCD-A VSP (p value = 0.046) but not with DND or poor outcome. CPP < = 70 mmHg had no significant relationship with TCCD-A VSP, DND or poor outcome. TCCD-A VSP was significantly related to DND (p value = 0.00018) but not to poor outcome. The combination of TCCD-A VSP and ICP > = 30 mmHg was significantly related to poor outcome (p value = 0.015), but the combination of TCCD-A VSP with CPP < = 70 mmHg was not. CONCLUSIONS Increased ICP, not decreased CPP, was related to VSP. The combination of TCCD-A VSP and increased ICP was predictive of poor outcome. Management of acute ASAH should include reduction of increased ICP especially when there is concomitant TCCD-A VSP.