Subarachnoid haemorrhage (SAH) may arise spontaneously or as a result of trauma. Spontaneous SAH accounts for about 5% of all strokes. Ruptured aneurysms are the cause of 85% of spontaneous SAH. The most characteristic clinical feature is sudden-onset severe headache. Other features include vomiting, photophobia, and focal neurological deficit or seizures, or both. As the headache may have insidious onset in some cases, or may even be absent, a high degree of suspicion is required to diagnose SAH with less typical presentations.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of surgical treatments for people with confirmed aneurysmal subarachnoid haemorrhage? What are the effects of medical treatments to prevent delayed cerebral ischaemia in people with confirmed aneurysmal subarachnoid haemorrhage? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2009 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
We found 6 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
In this systematic review we present information relating to the effectiveness and safety of the following interventions: endovascular coiling; surgical clipping; timing of surgery; and oral and intravenous nimodipine.
Subarachnoid haemorrhage (SAH) may arise spontaneously or as a result of trauma. Spontaneous SAH accounts for about 5% of all strokes. Ruptured aneurysms are the cause of 85% of spontaneous SAH. This review deals with only spontaneous aneurysmal SAH.
Without treatment, mortality rates of about 50% at 1 month after spontaneous aneurysmal SAH have been reported.
Treatment is aimed at prevention of re-bleeding from the same aneurysm. This can be performed by surgical clipping or by endovascular coiling.
In people suitable for either procedure, endovascular coiling has lower rates of poor functional outcome compared with surgical clipping, but it is also associated with increased rate of recurrent haemorrhage from the treated aneurysm and a higher rate of re-treatment for the same aneurysm. Most evidence is in small (<11 mm) aneurysms of the anterior circulation. Therefore, the conclusions cannot be applied to all aneurysms (particularly large and giant aneurysms, and aneurysms with broad necks).Factors that should be considered when deciding on the method of treatment include the morphology of the aneurysm, the age and clinical condition of the person, and the presence or absence of a space-occupying intracranial haematoma.
We do not know the optimal timeframe for carrying out surgical clipping or endovascular coiling after aneurysmal SAH. However, early surgery will prevent re-bleeding from the aneurysm, and is preferred in most people.
Oral nimodipine reduces poor outcome (death or dependence), secondary ischaemia, and CT/MRI evidence of infarction after aneurysmal SAH.
We found no evidence on the effects of intravenous nimodipine alone.