Simply speaking, this is any bleed that occurs within the head.
A subarachnoid haemorrhage is just one type of intracranial bleed which occurs over the surface of the brain, due to a weakened artery. It causes cerebro-spinal fluid to mix with the blood- hence a lumbar puncture (drawing off some spinal fluid)can often be used to detect a bleed. Although CT and MRI scanning will more likely have been carried out first.
There are around 8500 cases in the UK every year, predominantly in the 40-65 year age range, with 3 cases being women for every 2 of men. It is a potentially serious life threatening condition, where statistically around 10-15% die before getting to hospital and 50% within one month of the occurence.
The nature of the bleed will likely be different in each case as will other factors, but common in most cases will be headache, nausea, vomiting and neck stiffness.
Sometimes there is seizure, loss of consciousness and disorientation.
In 75% of cases a ballooning out of an artery forms, this is called an aneurysm where the vessel wall is thinner and bursts under pressure.
An aneurysm may have been slowly forming since birth or childhood.
An angiogram, which maps out the blood vessels in the brain, will be used to locate such potential weak points and there may be more than one.
Pre-disposing risk factors include smoking and high blood pressure.
The aim is to stop a bleed recurrence which is usually done by clipping or inserting platinum coils within the aneurysm.
In 15% of cases the cause is unknown - whatever weakness was there has gone - the angiogram will have been negative and it is said that no vascular abnormality was found. In 5% of cases there will be what is called an arterio-venous malformation (AVM) where arteries and veins have joined from birth in a haphazard manner.
After a SAH there is a short term risk of getting what is called a Vasospasm, where there is a narrowing of some blood vessels in the brain. This gives rise to an increased risk of a stroke, so medication such as nimodipine is likely to be prescribed as a precaution in most cases.
With a SAH, the blood surrounding the brain sets up an acute irritation but it will eventually be re-absorbed in a matter of weeks. In some cases the blood can cause problems with the normal drainage of the cerebrospinal fluid (CSF) which can build up and cause hydrocephalus - If this happens, then it will need to be drained off manually.
There is also a possibility that some people might have seizures or epilepsy due to abnormal electrical discharges in the brain.
General symptoms following a SAH
Timescales vary but many will be short term
- Short term memory
Lack of concentration
- Anxiety/Lack of confidence
Anxiety of family members
- Feeling stressed more easily
- Limb weakness-physio may be required
- Slurred speech/difficulty getting the right words
- Some problems with vision
- Some personality issues
NB: As there is a general lack of information about, I have put the above very brief list together from a number of sources. I hope you find it useful.
There will no doubt be persons who are members on this site who can offer their personal opinions on specific issues which we hope will be of help.
Please note I am not a medical professional, the above is a generalised guide only and you should always seek advice from your health professional/Specialist.