Patient education: Subdural hematoma and epidural hematoma (The Basics)

What are subdural hematomas and epidural hematomas? — These terms refer to bleeding on the surface (and outside) of the brain.

"Hematoma" means a collection of blood. The words "subdural" and "epidural" refer to the exact location of the bleeding (figure 1):

●A subdural hematoma is bleeding just under the tough, outer covering of the brain. This covering is called the "dura."

●An epidural hematoma is bleeding just under the skull on top of the dura. This type of hematoma is not common.

Although the bleeding is not actually in the brain, if there is a big blood clot, it can put pressure on the brain. This can lead to symptoms.

What causes subdural hematomas and epidural hematomas? — They can happen after an injury to the head. The most common causes include:

●A car crash

●A fall

●A physical attack or assault

If a head injury causes a blood vessel inside the skull to tear, it can lead to a hematoma. An "acute" hematoma happens in the first hours after the injury. If the bleeding continues, the hematoma can keep growing, days after the injury. Many people with a head injury that causes an epidural hematoma also have a skull fracture.

A subdural hematoma can also be "chronic." This type happens most often in older people whose brains have shrunk slightly due to age. In these people, a mild head injury can cause a tear in a small vein. This can then lead to bleeding on the brain's surface. The injury can be so mild that the person doesn't even notice it or remember it later. The hematoma grows slowly, over several days or weeks.

Rarely, a subdural hematoma or an epidural hematoma can happen without a head injury. This can happen if there is a problem with the blood vessels in the brain or a bleeding disorder. It can also happen if a brain infection causes a blood vessel to break.

What are the symptoms of a subdural hematoma or an epidural hematoma? — Some people pass out after getting a serious head injury and a large, acute hematoma. Other times, the symptoms appear later, as the hematoma puts pressure on the brain.

Symptoms depend on where the hematoma is and how big it is. They can include:

●Headache

●Vomiting

●Weakness

●Numbness

●Trouble walking

●Slurred speech or being unable to speak

●Acting less alert than normal

●Dizziness

●Confusion or trouble thinking

●Sleepiness

●Seizures

Will I need tests? — Yes. Tests include imaging tests that take pictures of your brain, such as:

●CT scan

●MRI

These tests can show where and how big the bleed is. They will also show whether it is a subdural hematoma or an epidural hematoma.

Your doctor or nurse will also do a "neurologic exam." During this, the doctor checks how your brain, nerves, and muscles are working.

How is a subdural hematoma or an epidural hematoma treated? — It depends on the type and size of the hematoma and your symptoms.

●Many people with epidural hematomas need surgery. Some people with subdural hematomas that are large or causing symptoms need surgery. The surgery involves draining the hematoma and relieving the pressure on the brain.

●If the hematoma is small, your doctor might recommend waiting to see if it gets better on its own. You might need to stay in the hospital during this time. In this case, the doctor will do a follow-up CT scan or MRI to confirm that the hematoma is going away.

●If you take certain medicines, your doctor might tell you to stop taking them for a time. Examples include aspirin, clopidogrel (brand name: Plavix), or "blood thinners" such as warfarin, dabigatran, apixaban, or rivaroxaban. Talk to the doctor who first prescribed these medicines about when and if you should start taking them again.

What will my life be like? — Many people who are treated for a subdural hematoma or an epidural hematoma recover fully. Others have long-term problems. It depends on how big the hematoma was, and whether it was causing serious symptoms. It also depends on the person's age and overall health. Your doctor can talk to you about what to expect as you recover.

More on this topic

Patient education: Head injury in adults (The Basics)
Patient education: Skull fractures (The Basics)