A subdural hematoma is a collection of blood between the skull and the brain. Specifically, blood collects under the dura, the tough, protective layer around the brain. This is most often caused by a head injury, but in rare cases, may occur spontaneously, as the result of an underlying medical condition. The blood, though technically outside of the brain itself, can cause pressure in the brain, which can be life-threatening.
Symptoms of subdural hematoma include the following:
-Headaches -Nausea/vomiting
-Dizziness -Limb weakness, tingling, or numbness
-Balance problems -Weakness on one side of the body
-Confusion -Memory loss
-Changes in behaviour -Drowsiness/ excessive tiredness
-Slurred speech -Personality changes/psychosis
-Blurry/double vision -Seizures
-Loss of consciousness -Apathy (lack of interest/motivation)
The onset and severity of symptoms depends on the severity of the head injury and the amount of bleeding. Age and health conditions can also affect the body’s response to a subdural hematoma. In a severe head injury, the person may become unconscious or start showing other symptoms immediately. In a milder injury or spontaneous hematoma, it may take days or even weeks for symptoms to appear.
In infants and very young children, subdural hematomas are often seen as a sign of child abuse, most notably, in Shaken Baby Syndrome. Symptoms in an infant include a bulging soft spot in the head, increased head circumference, high-pitched crying and irritability, poor feeding, persistent vomiting, increased sleepiness, and seizures.
The following conditions may increase your risk of developing a subdural hematoma.
-Taking blood thinner medication -History of multiple head injuries (seen often in athletes)
-Age (very old or very young) -Blood clotting disorder
-Victim of child abuse -Alcohol abuse
-Frequent falls -Having an intracranial shunt
Subdural hematomas are diagnosed using a CT scan or MRI for imaging of the head/brain. The bleed can be seen in these scans by a trained healthcare provider. Usually, these are routinely performed after a severe head injury, or in patients with a history of a minor head injury and/or symptoms of a subdural hematoma.
Some subdural hematomas will resolve on their own. In cases with a small hematoma and mild symptoms, the only treatment may be “watchful waiting.” The patient is observed for changes in symptoms, and repeat imaging is done to see if the subdural hematoma is improving. In severe cases, brain surgery is required to relieve the pressure caused by the hematoma. The surgeon may remove a part of the skull temporarily or drill small holes in the skull to relieve the pressure. Medications may also be used to decrease swelling and/or control seizures. In patients with clotting disorders, medication may be used to help the blood clot and stop the bleeding. Severe subdural hematoma patients may require a ventilator/life support in an intensive care unit.
The most severe complications of subdural hematoma include coma and even death. Brain herniation (movement of the brain tissue away from its intended space within the skull) is a life-threatening complication. Some patients may continue to have seizures requiring long-term anti-seizure medication after the hematoma has been treated. A subdural hematoma may increase the risk of another brain bleed, especially in older adults. Continued weakness, difficulty speaking, confusion, dizziness, headache, or difficulty concentrating may persist short-term or long-term.
Proper use of safety equipment to protect the head is one of the best ways to prevent a subdural hematoma (helmets, hard hats, seatbelts). Older adults should take special precautions to avoid falls. Anyone who develops symptoms of a subdural hematoma, especially after a head injury, no matter how minor it seemed, should seek medical attention right away.