Stroke
What is a stroke?
A stroke happens when the blood supply to the brain is interrupted due to a blocked or burst artery.
Types of stroke
If a stroke happens because of a blocked artery, it is called an ischaemic stroke.
If a stroke happens because of a burst artery, it is called a haemorrhagic stroke. This is a medical emergency that carries with it a high risk of death; therefore people who have a haemorrhagic stroke need to be admitted to the intensive care unit (ICU).
There are two types of haemorrhagic stroke:
- Intracerebral haemorrhage – This is when a blood vessel inside the brain bursts and bleeds into the brain tissue. Causes include high blood pressure, head injury, blood vessel abnormalities, bleeding into a brain tumour and infection.
- Subarachnoid haemorrhage – This is when a blood vessel on or near the surface of the brain bursts and bleeds into the space between the surface of the brain and the skull. The most common cause is an aneurism (a weakness in a blood vessel that leads to it bursting).
Symptoms of stroke
There are many possible symptoms of stroke, depending on the type of stroke and which area of the brain is damaged.
Symptoms of stroke can include:
- weakness on one or both sides of the body (e.g. face, arm and/or leg)
- difficulty controlling or coordinating movements
- difficulty speaking or swallowing
- difficulty with thinking and memory
- changes in vision or perception.
If the stroke is due to a burst blood vessel in the brain, symptoms may also include:
- severe headache
- nausea and vomiting
- seizures
- loss of consciousness.
Assessing someone who has had a stroke
When someone first has a stroke, a number of tests and procedures will need to be done to assess their situation. These may include:
- brain scans, such as magnetic resonance imaging (MRI) or computed tomography (CT) scans
- heart tests, such as an electrocardiogram (ECG) or echocardiogram (echo)
- blood vessels tests, such as an angiogram.
A range of other investigations may also be needed such as x-rays, blood tests and urine tests.
Regular observations will also be made to monitor their blood pressure, heart rate, temperature, blood sugar level, oxygen levels and breathing pattern.
Treating stroke
There is no medical treatment available that will repair brain damage caused by a stroke. In some people who have an ischaemic stroke, a treatment known as thrombolysis may be suitable. This involves giving a drug to break down the problem blood clot and allows blood flow to return to the brain.
In people who have had a haemorrhagic stroke, possible treatment options may include:
- inserting a drain to remove excess blood from the brain
- placing a metal clip around the neck of an aneurysm to prevent further bleeding (‘clipping’)
- threading tiny platinum coils into an aneurysm to block its blood flow and prevent further rupture and bleeding (‘coiling’).
What happens in intensive care?
- Monitoring of the heart rate, blood pressure, oxygen saturation and temperature. This will be seen on a bedside monitor.
- If the patient has a head injury they may have monitoring of the pressure in their brain (ICP monitoring).
- An arterial line may be inserted to monitor blood pressure and to take blood samples.
- Medication and intravenous fluids may be given via an intravenous cannula or a central venous catheter.
- If a patient is unconscious, or cannot breathe or swallow properly, an endotracheal tube will be inserted and they will be mechanically ventilated. Some patients who need to be ventilated for more than a week or two will have a tracheostomy tube inserted. The ventilated patient will require suctioning to remove secretions from the lungs and airways.
- If a patient is unable to eat, nutrition will be given via a nasogastric tube. This is a tube that is placed in the nose and goes down the throat into the stomach. Fluid can also be removed from the stomach via the nasogastric tube.
- Insertion of an indwelling catheter to drain and measure urine output.
- Chest x-rays and other tests such as blood tests, CT scan, MRI, echocardiogram, ECG and urine tests.
- Warming and/or cooling blankets may be needed.
- Sequential compression devices may be put on the legs to prevent deep vein thrombosis.
- An air mattress may be used to prevent pressure areas developing.