Epidural hematoma (also known as extradural hematoma) is a blood collection between the dura mater and the skull with a characteristic lens-shaped appearance on the CT scan. It can be present in up to 1-4% of traumatic head injuries.
Most cases (85%) occur due to arterial trauma (skull fracture with lesion of the middle meningeal artery). The other 15% occur due to venous lesions. Epidural hematomas caused by nontraumatic processes (autoimmune diseases, surgery) are rare.
SIGNS & SYMPTOMS:
At the presentation the patient may be asymptomatic or have various degrees of neurological deterioration.
The epidural hematoma often presents with a lucid interval: the person will lose consciousness for a moment but will feel better for hours after before deteriorating again.
Other clinical features are related to increased intracranial pressure (vomiting, headache, bradycardia, hypertension).
In neonates and children, irritability, vomiting, lethargy and seizures may occur.
A history of head trauma and physical examination with altered mental status or signs of intracranial pressure are helpful for the suspicion. The diagnosis is confirmed by a head CT scan showing a lens-shaped collection.
Ideally, the diagnosis should be made during the lucid interval (before the deterioration).
Other tests that are important include CBC, CMP, coagulation studies (PT, PTT) and blood typing and crossmatching.
Features associated with prognosis include the severity of the neurological deficits (GCS), pupillary abnormalities, hematoma volume, degree of midline shift and the severity of the associated trauma.
Since epidural hematoma is often present in a polytraumatized patient, it is important to use a systematic approach to stabilize the patient (A, B, C, D, E) before doing further interventions.
When everything else (ABC) is secure, the patient should have his neurological status assessed (e.g. GCS). If an epidural hematoma (or any other intracranial condition for that matter) is suspected a CT scan should be obtained promptly.
Most cases will require surgical evacuation of the hematoma as soon as possible. Adult patients with no neurological deficits and hematomas <30cm3, hematoma clot thickness <15mm and midline shift <5mm may be treated with observation (frequent imaging and neurological examination).
If the patient was being anticoagulated, the anticoagulation should be reversed (cessation of the drug, vitamin K 10mg IV slowly, infusion of Prothrombin Complex Concentrate or fresh frozen plasma – all to reach an INR <1.2).
SOURCES & FURTHER READING:
- Maugeri R et al. Conservative vs. Surgical Management of Post-Traumatic Epidural Hematoma: A Case and Review of Literature. Am J Case Rep 2015; 16:811-817.
- Bor-Seng-Shu E et al. Epidural hematomas of the posterior cranial fossa. Neurosurg Focus 16 (2):Clinical Pearl 1, 2004.
- Tataranu L et al. Extradural hematoma – is surgery always mandatory? Rom J Leg Med  45-50 .
- Brain Trauma Foundation. Severe TBI Guidelines. ©2010 Brain Trauma Foundation.