What is a subdural haematoma?
A haematoma is a collection of blood that has pooled outside of a blood vessel after it has leaked or burst.
Subdural haematomas form inside the skull in the subdural space. This is a space between two of the brain’s protective membranes called the dura mater and arachnoid mater. The leakage of blood into this space can place pressure on the brain, which can damage brain tissue.
A subdural haematoma can be life-threatening and needs urgent medical assessment.
What causes subdural haematomas?
Subdural haematomas usually occur following a head injury. Head injuries can be caused by road traffic collisions, falls, assaults or other accidents. Even a seemingly minor head injury such as a concussion can cause a subdural haematoma, particularly in someone with additional risk factors, such as being of older age, having a blood-clotting disorder or being on anticoagulant medication.
Symptoms of a subdural haematoma may develop immediately after a head injury or over the following days or weeks. This is why it is important to monitor for symptoms after a head injury and to follow medical advice given.
In rare cases, subdural haematomas can be caused by non-traumatic events, such as blood clotting disorders, being on medicines that affect blood clotting and, less commonly, other medical conditions.
Brain injury and me
Steven's story
“Steven Kelly had worked as an actor, musician, poet and comedian for the majority of his life. But following his brain injury, he worried that he’d lose his creative ability altogether.
“In November 2019, Steven was crossing the road on his way home from work when he was knocked down by a pushbike.
“He suffered a haematoma and a fractured skull which left him with balance problems, dizziness, bouts of confusion and sensory impairment.”
What happens during a subdural haematoma?
A head injury can cause the brain to suddenly move around within the skull. Small blood vessels can be damaged, causing them to leak blood into the subdural space. This is the space between the dura mater and the arachnoid mater, two of the brain’s protective membranes which, along with the pia mater, are collectively called the meninges.
The bleeding into this space is called a subdural haemorrhage, while the pooling of blood that collects in this space is called a subdural haematoma.
Symptoms of a subdural haematoma can include:
A severe headache that does not improve or gets steadily worse
Drowsiness or difficulty staying awake
Feeling or being sick
Memory problems
Weakness or difficulty moving one side of the body
Problems with balance
Blurred vision or double vision
Confusion
Slurred speech
Problems with swallowing
Loss of consciousness
Changes in personality or behaviour
Seizures
Call 999 immediately if you or someone else has had a head injury and they are unconscious or struggling to stay awake. You should also call 999 if there are problems with seeing, hearing, walking, balance, understanding, speaking or writing, a seizure, or bruising around the eyes without direct eye injury, bleeding from the ears or clear fluid coming out of the ears or nose following head injury.
You should go to A&E if you have had a head injury followed by vomiting, a headache that does not get better, changes in your behaviour or thinking skills or if you were unconscious but have now woken up. You should also go to A&E if you take anticoagulant medicine, have a blood-clotting condition or any other concerning symptoms after head injury. Do not drive yourself to A&E.
Call NHS 111 for any other concerns or if you are unsure what to do following a head injury.
How are subdural haematomas treated?
Upon arrival at hospital and following initial assessment, a brain scan such as computerised tomography (CT) or magnetic resonance imaging (MRI) may be needed to diagnose and locate the subdural haematoma.
Treatment depends on the size of the haematoma, the symptoms it is causing and its effect on the brain.
A small haematoma causing mild symptoms may be monitored without immediate treatment. Medicines may be given to help reduce swelling in the brain caused by the haematoma.
In more serious cases, surgery may be needed to remove the pooled blood. This can take two forms:
A surgical procedure known as a craniotomy might be performed, in which part of the skull is temporarily removed to allow access to the brain. The part of the skull that is removed is called a ‘bone flap’. The leaked and pooled blood is drained away, helping to relieve pressure on the brain. The bone flap is usually then replaced and secured.
Small holes may be drilled into the skull (called burr holes) to drain the leaked blood and relieve pressure on the brain.
What happens after a subdural haematoma is treated?
Following treatment for a subdural haematoma, a person will usually need to stay in hospital to recover. They will continue to be monitored by the medical team. The length of the hospital stay will depend on the type and severity of the haematoma, the treatment provided and the person’s individual needs.
The person may have rehabilitation to help manage the physical, cognitive or emotional impact of the haematoma. This can take place within the hospital, at a specialist brain injury rehabilitation unit or through community-based teams.
A person may be able to return directly home from hospital, but they will need to continue resting. The time needed to recover and return to usual activities varies from person to person.
For more information on these next stages, see our section Treatment and rehabilitation.
Recovery from any brain injury can be a long process, but with support it is possible to improve life after brain injury. Find out more about the support we can offer by visiting our Supporting you section.
