For literature searches we mainly used our personal database of references. This database has been prospectively built by daily search of PubMed in the past 10–15 years, by means of the following terms “subarachnoid hemorrhage [All Fields] OR subarachnoid haemorrhage [All Fields] OR aneurysm [All Fields] OR arteriovenous malformation [All Fields] OR perimesencephalic [All Fields]”. We also searched the Cochrane library with these terms. We mainly selected studies from the past 10 years,
SeminarSubarachnoid haemorrhage
Section snippets
Epidemiology
The incidence of subarachnoid haemorrhage was overestimated until brain imaging allowed accurate distinction between subarachnoid and intracerebral haemorrhage. In most populations the incidence is 6–7 per 100 000 person-years (after adjustment to age-standardised rates),2, 3 but is around 20 per 100 000 in Finland and Japan.2 Thus, a full-time general practitioner with 2000 patients will see, on average, one patient with subarachnoid haemorrhage about every 7–8 years. Although the incidence
Aneurysms
Intracranial aneurysms are not congenital, as was once believed, but develop in the course of life.7 The best estimate of the frequency of aneurysms for an average adult without specific risk factors is 2·3% (95% CI 1·7–3·1); this proportion increases with age.7 Saccular aneurysms arise at sites of arterial branching, usually at the base of the brain, either on the circle of Willis itself or at a nearby branching point (figure 1). Most intracranial aneurysms will never rupture. The rupture risk
Clinical features
Sudden headache is the most characteristic symptom of subarachnoid haemorrhage; in three out of four patients, the onset is within a split second or a few seconds.27 It is the only symptom in about a third of patients in general practice.32 Conversely, in patients who present with sudden headache alone in general practice, subarachnoid haemorrhage is the cause in one in ten patients.32 Apparently, common headaches with an exceptionally rapid onset outnumber subarachnoid haemorrhage in general
Management
Recommendations for general management and nursing are shown in panel 2. On admission, the first concern is to identify the cause of any reduction in consciousness or focal deficit, before these signs are attributed to the effect of the initial event; some of these causes require immediate intervention. In patients who survive the initial hours after the haemorrhage, three main neurological complications can threaten the patient with a ruptured intracranial aneurysm: rebleeding, delayed brain
Prevention
Three categories need to be considered here. First, there are patients with incidental aneurysms. Second, patients with subarachnoid haemorrhage might have one or more unruptured aneurysms. Last, the question of screening for aneurysms arises in patients who survive an episode of subarachnoid haemorrhage, and in first-degree relatives of patients with subarachnoid haemorrhage.
Search strategy and selection criteria
References (138)
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Lancet Neurol
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Quadrigeminal non-aneurysmal subarachnoid hemorrhage: a true variant of perimesencephalic subarachnoid hemorrhage: case report
Clin Neurol Neurosurg
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Nonaneurysmal subarachnoid hemorrhage: prevalence of perimesencephalic hemorrhage in a consecutive series
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Prospective study of sentinel headache in aneurysmal subarachnoid haemorrhage
Lancet
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Thunderclap headache as first symptom of cerebral venous sinus thrombosis
Lancet
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Resuscitation
(2002) - et al.
Management of poor-grade patients with aneurysmal subarachnoid hemorrhage in the acute stage: importance of close monitoring for neurological grade changes
Surg Neurol
(2004) - et al.
International Subarachnoid Aneurysm Trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised trial
Lancet
(2002)