A client who is admitted to the ER for head trauma is diagnosed with an epidural hematoma. The underlying cause of epidural hematoma is usually related to which of the following conditions?
A. Laceration of the middle meningeal artery.
B. Rupture of the carotid artery.
C. Thromboembolism from a carotid artery.
D. Venous bleeding from the arachnoid space.
Correct Answer: A. Laceration of the middle meningeal artery.
Epidural hematoma or extradural hematoma is usually caused by laceration of the middle meningeal artery. Most epidural hematomas result from arterial bleeding from a branch of the middle meningeal artery. The anterior meningeal artery or dural arteriovenous (AV) fistula at the vertex may be involved.
Option B: Embolic strokes occur when clots migrate from the source to block more distal cerebral arteries causing cessation of brain tissue perfusion and ischemia. The embolic source can be cardiac, aortic, arterial, from a venous origin in the pelvis or lower limbs with the presence of a cardiac shunt resulting in paradoxical embolism, or an unknown source.
Option C: An embolic stroke is a thromboembolism from a carotid artery that ruptures. Emboli can happen due to different mechanisms including blood stasis in an abnormal, structurally enlarged left cardiac chamber such as left ventricular aneurysm with subsequent thrombus formation, material detachment from structurally abnormal calcific degenerative valves, or embolus passage from the venous to the arterial circulation (paradoxical embolism) because of the presence of right to left cardiac shunt such as Patent Foramen Ovale (PFO).
Option D: Venous bleeding from the arachnoid space is usually observed with a subdural hematoma. Up to 10% of EDHs are due to venous bleeding following the laceration of a dural venous sinus. In adults, up to 75% of EDHs occur in the temporal region. However, in children, they occur with similar frequency in the temporal, occipital, frontal, and posterior fossa regions.
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