Head injury, severe

The National Institute for Health and Clinical Excellence (NICE) defines a head injury as any trauma to the head other than shallow injuries on the surface of the face.

A severe head injury may cause:

• loss of consciousness
• fits or seizures, when the body suddenly moves uncontrollably
• problems with the senses, such as loss of hearing or double vision

Glasgow Coma Scale

Head injuries are assessed by healthcare professionals using the Glasgow Coma Scale (GCS). This is a scale from 3 to 15 that is used to identify how serious the injury is and how severely the brain has been damaged (with 3 being most severe and 15 least severe).

A head injury is usually classed as being severe if someone has a GCS score of eight or less. See Diagnosing severe head injury for more information.

Brain injury

A severe head injury can cause brain damage (a brain injury). Even though the brain is protected by the bone covering of the skull, the surface of the brain can tear or bruise as it bumps against the skull. This can damage blood vessels and nerves.

These injuries can cause bleeding, blood clots or a build-up of fluid, which puts pressure on the brain. This can sometimes lead to a brain injury, which can be either temporary or permanent. Brain injuries can have many different effects, including:

• emotional effects
• behavioural effects
• physical effects

How common are head injuries?

Head injuries are more common in men and children. The most common causes of head injuries are falls, assaults and road traffic accidents.

Outlook

Severe head injuries should always be treated in hospital. See Symptoms of severe head injury for signs of a severe head injury. Treatment in hospital will involve:

• observing the condition for any changes
• running tests to check for further damage
• treating any other injuries

Of the people admitted to hospital due to a head injury, 1-3% could develop a serious complication that may require surgery. Most people (around 97%) are able to go home after 48 hours.

The rate of death after a head injury is 0.2%. This means that for every 1,000 people who attend an accident and emergency (A&E) department at a hospital with a head injury, two of them may die. 

If you have a head injury, it could affect your ability to drive. It is your legal obligation to inform the Driver and Vehicle Licensing Agency (DVLA) about a medical condition that could have an impact on your driving ability. Go to the Directgov website to find out how to tell the DVLA about a medical condition. 

Glossary

Brain
The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.