Extradural hemorrhage

Definition:

Extradural hemorrhage is a disorder caused by bleeding between the inner skull wall and the outer membrane covering the brain, called the "dura mater" (which literally means "tough mother") or "dura."

Alternative Names:

Extradural hematoma; Epidural hematoma

Causes, incidence, and risk factors:

About 10% of brain injuries are moderate to severe. An even smaller proportion involve extradural (epidural) hemorrhage. 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 extradural hemorrhage occurs when there is a rupture of a blood vessel, usually an artery, which then bleeds into the space between the "dura mater" and the skull. The affected vessels are often torn by skull fractures.

This is most often the result of a severe head injury, such as those caused by motorcycle or automobile accidents. Extradural hemorrhages can be caused by venous bleeding in young children.

Rapid bleeding causes a collection of blood (hematoma) that presses on the brain, causing a rapid increase of the pressure inside the head (intracranial pressure), which may result in additional brain injury.

An extradural hemorrhage is an emergency because it may lead to permanent brain damage and death if left untreated. There may be a rapid worsening within minutes to hours, from drowsiness to coma and death.

Symptoms:

The health care provider should be consulted for any head injury that results in even a brief loss of consciousness or if other symptoms are present after head injury (even without loss of consciousness).

The typical symptom pattern of loss of consciousness, followed by alertness, then loss of consciousness again may not appear in all people, but is highly indicative of an extradural hemorrhage.

The most important symptoms of extradural hemorrhage are:

Headache, severe
Drowsiness
Confusion
Nausea or vomiting may accompany the headache
Dizziness
Enlarged pupil in one eye
Weakness of part of the body, usually on the opposite side from the side with the enlarged pupil
Head injury or trauma followed by loss of consciousness, an alert period of time, then rapid deterioration back to unconsciousness

Note: Symptoms usually occur within minutes to hours after a head injury and indicate an emergency situation.

Signs and tests:

The neurologic examination may show "focal neurologic deficits" (signs of malfunction of a specific part of the brain, for instance arm weakness on one side) or may indicate increased intracranial pressure.

If there is increased intracranial pressure, emergency surgery may be needed in order to relieve the pressure within the head and spare the brain from further injury.

A head CT scan will confirm the diagnosis of an extradural hemorrhage and will pinpoint the exact location of the hematoma and any associated skull fracture.

Treatment:

An extradural hemorrhage is an emergency condition! Treatment goals include taking measures to save the person's life, controlling symptoms, and 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 drainage of the blood from the brain.

Large hematomas or solid blood clots may need to be removed through a larger opening in the skull (craniotomy).

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.

Expectations (prognosis):

An extradural hemorrhage has a high risk of death without prompt surgical intervention. Even with prompt medical attention, a significant risk of death remains.

Complications:

There is a risk of permanent brain injury whether the disorder is treated or untreated. Symptoms (such as seizures) may persist for several months, even after treatment, but in time they usually reduce in frequency or disappear completely. Seizures may begin as many as 2 years after the injury, however.

In adults, most recovery occurs in the first 6 months, with some improvement over approximately 2 years. Children usually recover more quickly and completely than adults.

Incomplete recovery is the result of brain damage. Other complications include permanent symptoms (such as paralysis or loss of sensation which began at the time of the injury), uncal herniation (herniation of the brain), and normal pressure hydrocephalus (water on the brain).

Calling your health care provider:

Go to the emergency room or call the local emergency number (such as 911) if symptoms of extradural hemorrhage occur.

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 the local emergency number (such as 911) if emergency symptoms develop after treatment, including: breathing difficulties, convulsions/seizures, decreased responsiveness, loss of consciousness, enlarged pupils, and uneven pupil size.

Prevention:

Epidural hemorrhage may not be preventable once a head injury has occurred.

Minimize the risk of head injury:

Use appropriate safety equipment (such as hard hats, bicycle or motorcycle helmets, and seat belts) when involved in activities that carry a significant risk of brain injury.
Use appropriate safety behaviors. 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.

Review Date: 8/1/2002
Reviewed By: Lucas Restrepo, M.D., Clinical Instructor, Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, Review provided by VeriMed Healthcare Network.

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