143.A 20-year-old man was found on the ground next to his car after it hit
a tree on the side of the road. Bystanders state that the man got out of his car
after the collision but collapsed within a few minutes. Paramedics subse-
quently found the man unconscious on the side of the road. In the ED, his
BP is 175/90 mm Hg, HR is 65 beats per minute, temperature is 99.2°F, R R
is 12 breaths per minute, and oxygen saturation is 97% on room air. Physi-
cal examination reveals a right-sided fixed and dilated pupil. A head CT is
shown below. Which of the following is the most likely diagnosis?
Trauma 137a. Epidural hematoma
b. Subdural hematoma
c. Subarachnoid hemorrhage (SAH)
d. Intracerebral hematoma
e. Cerebral contusion
(Reproduced, with permission, from Knoop KJ, Stack LB, Storrow AB.Atlas of Emergency
Medicine. New York, NY: McGraw-Hill, 2002: 162.)