ABSTRACT
Has there been an episode of loss of consciousness? Sudden loss of consciousness occurs in half of all patients sustaining a subarachnoid haemorrhage (SAH) and it often lasts for more than one hour.
● Classification of acute headache Vascular
Are there symptoms of meningism? Ask about photophobia and neck stiffness. Symptoms of meningism increase the likelihood of diagnoses such as meningitis (bacterial or viral), subarachnoid haemorrhage and encephalitis. Note that the history in most of these cases will be short (hours rather than days) and, in the case of SAH, meningism usually takes more than three hours to develop. A longer history (days to weeks) with symptoms of meningitis should prompt consideration of meningeal tuberculosis (TB), particularly in patients born in countries with a high incidence of TB.
