This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Clinical features

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

Typically, the patient afflicted by subarachnoid haemorrhage is over 40 years. The nature and severity of the symptoms depend upon the severity of the bleed.

These include:

  • sudden severe headache ("my worst headache ever") - worse and different in character to previous migraine; may bring the patient to their knees
  • premonitory headaches occur in the preceding weeks in 25 to 50% of cases; overlooked as often by the patient as by the physician
  • loss of consciousness or epileptic seizure occurs in 50% of cases; usually transient, sometimes prolonged
  • with less severe bleeding, the patient tends to present with a mild headache or delirium
  • bigger bleeds may cause nausea, vomiting and convulsions
  • meningism often develops with 3-12 hours
  • coma or a depressed level of consciousness may result from the direct effect of the haemorrhage or from the mass effect of an associated intracerebral haematoma
  • focal signs, e.g. limb weakness, dysphasia may result from a haematoma
  • a "reactive hypertension" is common - the patient undergoes a rise in blood pressure with no evidence of pre-existing hypertension which may last for several days
  • presence of a III nerve palsy indicates direct nerve damage from a posterior communicating artery or basilar artery aneurysm, or transtentorial herniation
  • fundus examination may reveal subhyaloid or vitreous haemorrhages, or papilloedema
  • plantar responses are usually extensor
  • back pain may arise from blood in the spinal theca

Related pages

Create an account to add page annotations

Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.