Subdural Hematoma

(Extra-axial Haematoma; Subdural Haemorrhage; SDH)


A hematoma is a collection of blood. A subdural hematoma develops in the space between the covering of brain (the dura) and the inside of the skull. This pool of blood can put pressure on the brain and cause a range of symptoms.


A subdural hematoma is most often caused by a head injury. The injury may be caused by traumas such as falls, car accidents, or physical abuse. It can also occur spontaneously.
Head Injury
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Risk Factors

Factors that increase your chance of a subdural hematoma include:


The blood may pool quickly or take some time to build up. This will affect how fast symptoms develop. The subdural hematoma may be:
After a head injury, a subdural hematoma may cause the following symptoms:
Seek medical care right away if you have any of these symptoms after a head injury.


Your doctor will ask about your symptoms and medical history. A physical exam will be done. You may also be referred to a specialist for additional testing.
Imaging tests evaluate the brain and surrounding structures. This can be done with:
Your brain function may be assessed. This can be done with:
Your bodily fluids may be tested. This can be done with blood tests.


Talk with your doctor about the best treatment plan for you. Treatment will depend on the size and severity of the hematoma. It will also be based on your specific symptoms.
Treatment options include the following:

Monitor and Observe

A minor injury with little or no symptoms may not need treatment. Your doctor may simply ask that you watch for any new symptoms. It can take days and weeks for some symptoms to develop.


Medication may be given to relieve symptoms. Some medications may include:
  • Antiseizure medication—if seizures have occurred
  • Steroids—to decrease brain swelling.


Surgery may be needed to relieve pressure on the brain. Surgical procedures that may be considered include:
  • A small hole may be made in the scalp and skull. It will allow the blood clot to drain out of the skull.
  • A section of the skull may be removed. This is called a craniotomy .


To help reduce your chance of a head injury:


American Academy of Otolaryngology—Head and Neck Surgery

Brain Injury Association of America


Brain Injury Canada

Ontario Brain Injury Association


Servadei F, Compagnone C, Sahuguillo J. The role of surgery in traumatic brain injury. Curr Opin Crit Care. 2007;13(2):163-168.

Subdural hematoma. EBSCO Dynamed website. Available at: Updated March 17, 2014. Accessed June 2, 2014.

Subdural haematoma. Patient UK website. Available at: Updated September 28, 2011. Accessed June 2, 2014.

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