Diagnosing a subarachnoid haemorrhage
If you may have a subarachnoid haemorrhage, immediate hospital transfer is necessary to confirm the diagnosis.
A computerized tomography (CT) scan is used to check for evidence of brain haemorrhage. This involves taking a series of X-rays, which a computer then makes into a detailed 3D image.
In some cases, a subarachnoid haemorrhage isn’t picked up by a CT scan. If a CT scan is negative, but symptoms strongly suggest a haemorrhage, a test called a lumbar puncture will usually be carried out.
A lumbar puncture involves a needle being inserted into the lower part of the spine, so fluid that surrounds and supports the brain and spinal cord (cerebrospinal fluid) can be sampled. The fluid collected will then be sent to the laboratory for analysis.
Planning treatment
If the results of a CT scan or lumbar puncture confirm you’ve had a subarachnoid haemorrhage, you’ll usually be referred to a neurologist.
Further tests are usually needed to help plan treatment, which may include either:
- computed tomography angiography (CTA) – using a CT scan
- magnetic resonance angiography (MRA) – using an MRI scan
Both of these tests are carried out similarly as a regular scan. However, a special dye is injected into a vein (usually in your arm or hand) which contrasts blood vessels and tissues.
Occasionally, an angiogram may be needed. This involves inserting a thin tube called a catheter into one of your blood vessels (usually in the groin). A local anaesthetic is used where the catheter is inserted.
Using a series of X-rays displayed on a monitor, the catheter is guided into the blood vessels in the neck that supply blood to the brain. Once in place, special dye is injected through the catheter and into the arteries of the brain. This dye casts a shadow on an X-ray, so the outline of the blood vessels can be seen and the exact position of the aneurysm can be identified.
Treating subarachnoid haemorrhages
If the diagnosis of subarachnoid haemorrhage is made, or is strongly suspected, referral and transfer to a specialized unit in neuroscience is done.
These units have a range of equipment and treatments to support many of the body’s vital functions, such as breathing, blood pressure and circulation.
In more severe cases, transfer to the intensive care unit (ICU) may be recommended.
Medication
Nimodipine
One of the main complications of a subarachnoid haemorrhage is secondary cerebral ischaemia. This occurs when the blood supply to the brain is reduced significantly, wherein inadequate support to the brain’s normal function. is where the supply of blood to the brain becomes dangerously reduced, disrupting the normal functions of the brain, causing brain damage.
You’ll usually be given a medication called nimodipine to reduce the chances of this happening. This is normally taken for three weeks, until the risk of secondary cerebral ischaemia has passed.
Side effects of nimodipine are uncommon, but can include:
- flushing
- feeling sick
- increased heart rate
- headaches
- a rash
Pain relief
Medication can be effective in relieving the severe headache associated with a subarachnoid haemorrhage.
Commonly used analgesics include morphine and a combination of codeine and paracetamol.
Other medications
Other medications that may be used to treat a subarachnoid haemorrhage include:
- anticonvulsants, such as phenytoin – which may be used to prevent seizures
- antiemetics, such as promethazine – which can stop the nauseated feeling and vomiting
Surgery and procedures
If scans show an aneurysm to be the cause of the subarachnoid haemorrhage, a procedure to repair the affected blood vessel and prevent rebleeding may be recommended.
This can be carried out using one of two main techniques. These are described below.
Neurosurgical clipping
Neurosurgical clipping is carried out under general anaesthesia, meaning that throughout the procedure the patient will be unconcious. A cut is made in your scalp (or sometimes just above your eyebrow) and a small flap of bone removed, so the surgeon can access your brain. This type of operation is known as a craniotomy.
When the aneurysm is located, the neurosurgeon (an expert in surgery of the brain and nervous system) will clamp the aneurysm with a metal clip. After the bone flap has been replaced, the scalp is stitched together.
Over time, the blood vessel lining will heal along where the clip is placed, permanently sealing the aneurysm and preventing it from growing or rupturing again.
Endovascular coiling
Endovascular coiling is also usually carried out under general anesthesia. The procedure involves inserting a thin tube called a catheter into an artery in the leg or groin. The tube is guided through the network of blood vessels into the head and into the aneurysm.
Tiny platinum coils are then passed through the tube and into the aneurysm. Once the aneurysm is full of coils, blood can’t enter it. This means the aneurysm is sealed off from the main artery, preventing it from growing or rupturing again.
Coiling versus clipping
The choice of whether to do clipping or coiling is used will depend on the size, location, and shape of the aneurysm.
Coiling is often the preferred technique because it has a lower risk of short-term complications (such as seizures) than clipping, although the long-term benefits over clipping are uncertain.
Those who underwent coiling usually have a shorter hospital stay than those who had clipping. Overall recovery time can be shorter for those who had coiling.
However, when these types of surgery are carried out as an emergency procedure, your recovery time and hospital stay depend more on the rupture’s severity than the type of surgery used.