Cerebral edema is when fluid builds up around the brain, causing an increase in pressure known as intracranial pressure.
Swelling or inflammation is part of the body's natural response to injury. Edema refers to swelling due to trapped fluid, and it can happen anywhere in the body. If edema occurs in the brain, however, it can cause severe complications.
Cerebral edema can restrict the supply of blood to the brain. Blood carries oxygen to the brain, which the brain requires to function. A lack of oxygen in the brain can damage brain cells or cause them to die.
Intracranial pressure (ICP) can affect specific regions of the brain or the whole brain depending on the underlying cause.
Cerebral edema can cause irreversible damage and, in some cases, be fatal.
Symptoms of cerebral edema may include:
- a headache
- memory problems
- difficulty speaking
- vision loss
- neck pain
- difficulty moving
- loss of consciousness
The symptoms will vary depending on the severity and underlying cause of the swelling.
The ICP associated with cerebral edema can have a range of different causes, including:
- Traumatic brain injury: A traumatic brain injury is an acute trauma, such as from a fall or vehicle accident.
- Ischemic stroke: An ischemic stroke occurs when a blood clot restricts the flow of oxygen to the brain. A lack of oxygen can damage the brain cells and cause swelling and pressure.
- Brain tumor: A brain tumor can press against other areas of the brain or prevent fluid from leaving the brain, causing elevated ICP.
- Infection: Infections caused by bacteria or a virus can cause swelling in the brain. For example, encephalitis is an infection that causes inflammation in the brain, and elevated ICP may develop as a result.
- Brain hemorrhage: A brain hemorrhage occurs when a blood vessel in the brain ruptures and leaks. This causes inflammation and an increase in ICP.
- High altitude: Cerebral edema can also occur above altitudes of around 4,000 meters.
Diagnosing cerebral edema can be challenging, as there are many potential causes and the symptoms may vary considerably.
To make a diagnosis, a doctor may do:
Cerebral edemas require immediate medical attention to reduce the risk of permanent damage or death.
Treatments will vary depending on the severity and underlying cause of ICP, but may include:
- Medication: Doctors will use drugs to reduce swelling or blood clots. Examples include warfarin, which thins the blood and reduces the chances of blood clots. In some cases, a doctor may recommend aspirin, but current guidelines no longer advise this for most people, because of the risk of bleeding.
- Surgery: In severe cases, surgery may be necessary to reduce ICP. Surgery could involve removing a part of the skull and repairing the damage, such as a ruptured blood vessel. Ventriculostomy is another possible procedure. It involves inserting a plastic tube into the skull to drain excess fluid and reduce ICP.
- Hypothermia: This form of therapy involves lowering the body temperature, which can reduce swelling in the brain.
- Osmotherapy: Osmotherapy involves using medications to remove water from the brain to help increase blood flow to the brain and reduce ICP.
Cerebral edemas can have severe and irreversible consequences. The outlook can vary considerably, depending on the precise location and severity of the edema, as well as how quickly a person receives treatment.
It is crucial for doctors to provide immediate and appropriate medical attention to minimize the risk of complications.