Which of the following is the most likely diagnosis for this patient’s condition?
This patient presents to the Emergency Department after a high-speed motor vehicle accident. On examination, he is tachycardic, mildly tachypneic, and has an altered mental status (somnolent). The first step in evaluating this trauma patient involves the primary survey. The primary survey is also known as the “ABCDEFs” of trauma. This stands for Airway, Breathing, Circulation, Disability, Exposure, and FAST exam (Focused Assessment with Sonography in Trauma). Each letter should be assessed in alphabetical order to avoid missing a time sensitive life-threatening condition. The primary survey should be conducted prior to taking a full history.
After the primary survey, a more detailed physical exam (secondary survey) is conducted, followed by interventions and a focused patient history. A noncontrast CT scan of the head is a reasonable test for this patient given his significant mechanism of injury and altered mental status on exam. The CT scan shows a hyperdense (white) biconvex area on the right side of the brain. This white area indicates the presence of fresh blood on the CT scan. Keep in mind that CT scans are read as if you are looking up from the patient’s feet to their head. This means left-right directionality is reversed. See image below.
A hyperdense area with a sickled or crescent-shaped appearance would indicate an acute subdural hemorrhage (Choice A). This is caused by tearing of the cerebral bridging veins. Hyperdense areas throughout the brain tissue itself would indicate an intraparenchymal hemorrhage (Choice B). Hyperdense areas around the sulci of the brain and a starfish appearance would indicate a subarachnoid hemorrhage (Choice D). Subarachnoid bleeding is caused by rupturing of a brain aneurysm or an arteriovenous (AV) malformation. Subarachnoid bleeding can also be associated with trauma.
This patient’s CT image shows an epidural hemorrhage (Choice C), indicated by the biconvex lens shaped area of blood. This is caused by tearing of the middle meningeal artery. Treatment of all types of intracranial bleeding involves general supportive care, airway management (i.e., endotracheal intubation for GCS < 8), elevating the head of the bed to 30 degrees to lower intracranial pressure (ICP), managing pain and sedation (lowers ICP), blood pressure maintenance (goal SBP <140mmHg), reversal of coagulopathy, neurosurgical evaluation for possible operative intervention, and providing ICP lowering treatments (mannitol or hypertonic 3% NaCl) when concerned about elevated ICP or brain herniation.