A B C D E F G H I J K L M N O P R S T U V W

SUBARACHNOID HAEMORRHAGE - BRAIN ANEURYSMS

What is a Subarachnoid Haemorrhage ?

The arachnoid is a thin membrane that covers the brain, behaving very much like cling-film . Within this membrane, travel the major arteries supplying the brain. If one of these bursts, a subarachnoid haemorrhage occurs. The main symptom is headache, worse than any other that the patient has had before. There is also usually vomiting and pain on looking at light. Symptoms are usually so severe that you will need to go straight to hospital, and occasionally may become comatose. Some people with mild haemorrhage do not see a doctor: they think they have a simple headache or migraine.

How does a Subarachnoid Haemorrhage occur ?

It is a rare condition affecting only 1 person in every 10 000. Most sufferers have a weak spot, growing like a tiny balloon out of the side of an artery. This is called an aneurysm. It has been suggested that smoking may weaken a blood vessel and that high blood pressure may cause the aneurysm to burst. A few people appear to be born with an abnormal area of weak blood vessels. This is called an arteriovenous malformation (AVM). In some instances, no cause is ever found: it is likely that there is a tiny aneurysm or AVM too small to show up on tests. This is destroyed by the haemorrhage and is unlikely ever to bleed again.

Treatment involved for a Subarachnoid Haemorrhage

When a subarachnoid haemorrhage is suspected, you will normally be transferred rapidly to the nearest neurosurgical centre. There the diagnosis will be confirmed by a computerized x-ray (CT) or a magnetic resonance scan (MRI). It is often necessary to do a lumbar puncture, a test where fluid surrounding the brain and spinal cord is examined by removing some through a needle placed briefly in the low back. You will be confined to bed. A drip of intravenous fluid is given to ensure adequate fluid intake. A number of drugs, including painkillers, will be given.

Some people can go on to suffer a stroke after the haemorrhage: this is due to a narrowing of the brain arteries called vasospasm . The stroke may take the form of weakness or mild confusion. There is no way of predicting who will have this vasospasm and the only help that can be given is to prevent dehydration and provide certain drugs which might widen the artery. Most patients will undergo an angiogram: a test where dye is injected so that the arteries of the brain can be seen (together with any aneurysm or AVM), on a special screen. The test is performed with either general or local anaesthetic. For this test, an artery in the groin is punctured, allowing a thin tube to be passed up to the brain vessels. Dye is injected and x-rays taken to show the possible cause. Having discovered an aneurysm or AVM, the decision concerning operation then needs to be made. This operation may be a traditional one, involving opening the skull.

A newer approach performed by the radiologist, consists of sealing the aneurysm by inserting platinum coils into the artery itself. This uses a tube similar to the one used for the initial x-ray. Open operation has a proven track record, but is theoretically more dangerous. « Endovascular coiling » is to some extent still experimental : it is not used in all centres, so that trials are underway to see which approach is best. With an aneurysm, the timing of the operation can be difficult. Too early a procedure can worsen the vasospasm. If left too late, further bleeding may occur. In the elderly or the frail, the risk of operating may be greater than the risks of another bleed. In this case, surgery will not be suggested. The operation consists of opening the head (craniotomy). With the aid of a microscope, the aneurysm is found, and a metal clip similar to a clothes peg is used to clip the neck of the aneurysm. This seals it off without damaging the main artery. Sometimes the aneurysm is packed with a type of glue to stop if from bleeding again. For an AVM, an operation to remove it is sometimes possible, depending on its position. Sometimes it may be managed with radiotherapy. All operations carry some risks but this is usually less than the risk of another bleed.

After Treatment

Some patients will sustain another bleed from the same source, often in the first week after the original bleed. Treating the blood pressure, avoidance of dehydration, and rest are usually the main parts of after-care. You will have to rest in bed for a few days and the intravenous drip will be removed. It will probably be possible for you to leave hospital about 3 weeks after the haemorrhage and you will need 6 weeks of convalescence before working. If you should be found to have more than one aneurysm, the one that has ruptured is dealt with first. If the second aneurysm cannot be dealt with immediately, this may be done 3 months later. You cannot drive after your haemorrhage and the DVLC needs to be notified. The licence will be withdrawn for up to one year. One can then lead a normal life. Treating any raised blood pressure is important, since this reduces the risk of another bleed. It will be necessary to have your blood pressure checked regularly. It is a good idea to give up smoking.

Effects on the family of a Subarachnoid Haemorrhage

Close friends and family will be concerned by the sudden illness, and will be reassured to know that many patients with this condition return to a perfectly normal life. However, they will need to take over some of the responsibilities of the patient for the 6 to 8 weeks after the initial attack.