Subarachnoid haemorrhage: diagnosis and treatment.

In this review the diagnosis and management of the acute phase of subarachnoid haemorrhage (SAH) are discussed. CT is a sensitive method of predicting a ruptured aneurysm in patients with SAH. If angiography does not reveal an aneurysm, the bleeding pattern on CT may predict if a patient is still at risk of rebleeding. Spectophotometric analysis of the CSF is a reliable method of distinguishing between traumatic tap and SAH and is a sensitive method of detecting SAH even 4 weeks after the bleeding. Many kinds of treatment can be considered in SAH, but few have been tested in well-conducted clinical trials. Based on the study methodology, different levels of evidence of treatment effectiveness can be distinguished. The effectiveness of nimodipine in reducing poor outcome has the most evidence in favour of it.