An epidural hematoma is bleeding between the inside of the skull and the outer covering of the brain (called the "dura").
Extradural hematoma; Extradural hemorrhage
An epidural hematoma is often caused by a skull fracture during childhood or adolescence. This type of bleeding is more common in young people because the membrane covering the brain is not as firmly attached to the skull as it is in older people.
An epidural hematoma occurs when there is a rupture of a blood vessel, usually an artery. The blood vessel then bleeds into the space between the "dura mater" and the skull.
The affected vessels are often torn by skull fractures. The fractures are most often the result of a severe head injury, such as those caused by motorcycle or automobile accidents. Epidural hematomas can be caused by bleeding from a vein (venous bleeding) in young children.
Rapid bleeding causes a collection of blood (hematoma) that presses on the brain. The pressure inside the head (intracranial pressure) increases quickly. This pressure may result in additional brain injury.
An extradural hemorrhage is an emergency. It may lead to permanent brain damage and death if left untreated. It may get worse very quickly, progressing from drowsiness to coma and death within minutes to hours.
The typical pattern of symptoms that indicate an epidural hematoma is a loss of consciousness, followed by alertness, then loss of consciousness again. But this pattern may NOT appear in all people.
The most important symptoms of an epidural hematoma are:
- Drowsiness or altered level of alertness
- Enlarged pupil in one eye
- Headache (severe)
- Head injury or trauma followed by loss of consciousness, a period of alertness, then rapid deterioration back to unconsciousness
- Nausea or vomiting
- Weakness in part of the body, usually on the opposite side from the side with the enlarged pupil
The symptoms usually occur within minutes to hours after a head injury and indicate an emergency situation.
Sometimes, bleeding does not start for hours after a head injury. The symptoms of pressure on the brain also do not occur right away.
Exams and Tests
The brain and nervous system (neurological) examination may show that a specific part of the brain is not working well (for instance, there may be arm weakness on one side). The exam may also indicate increased intracranial pressure.
If there is increased intracranial pressure, emergency surgery may be needed to relieve the pressure and prevent further brain injury.
An epidural hematoma is an emergency condition. Treatment goals include:
- Taking measures to save the person's life
- Controlling symptoms
- Minimizing or preventing permanent damage to the brain
Life support measures may be required. Emergency surgery is almost always necessary to reduce pressure within the brain. This may include drilling a small hole in the skull to relieve pressure and allow blood to drain from the brain.
Medications used in addition to surgery will vary according to the type and severity of symptoms and brain damage that occurs.
Anticonvulsant medications (such as phenytoin) may be used to control or prevent seizures. Some medications called "hyperosmotic agents" (like mannitol, glycerol, and hypertonic saline) may be used to reduce brain swelling.
An epidural hematoma has a high risk of death without prompt surgical intervention. Even with prompt medical attention, a significant risk of death and disability remains.
There is a risk of permanent brain injury, even if the disorder is treated. Symptoms (such as seizures) may persist for several months, even after treatment. In time they may become less frequent or disappear completely. Seizures may begin up to 2 years after the injury.
In adults, most recovery occurs in the first 6 months. Usually there is some improvement over approximately 2 years. Children usually recover more quickly and completely than adults.
Brain damage can lead to incomplete recovery. Other complications include permanent symptoms, such as:
- Herniation of the brain and permanent coma
- Normal pressure hydrocephalus, which can lead to weakness, headaches, incontinence, and difficulty walking
- Paralysis or loss of sensation (which began at the time of the injury)
When to Contact a Medical Professional
Go to the emergency room or call 911 if symptoms of epidural hematoma occur.
Spinal injuries often occur with head injuries. If you must move the person before help arrives, try to keep his or her neck still.
Call your health care provider if symptoms persist after treatment, including memory loss, difficulty maintaining attention, dizziness, headache, anxiety, speech difficulties, and complete or partial loss of movement in part of the body.
Go to the emergency room or call 911 if emergency symptoms develop after treatment, including breathing difficulties, convulsions/seizures, decreased responsiveness, loss of consciousness, enlarged pupils, and uneven pupil size.
An epidural hematoma may not be preventable once a head injury has occurred.
To minimize the risk of head injury, use appropriate safety equipment (such as hard hats, bicycle or motorcycle helmets, and seat belts).
Follow general safety rules. For example, do not dive into water if the water depth is unknown or if rocks may be present. Use appropriate safety precautions in sports, recreation, and work. Drive safely.
Biros MH, Heegaard WG. Head injury. In: Marx JA, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, PA: Elsevier Mosby; 2009:chap 38.