Neurology

Question 1

What does an uncal/transtentorial herniation do?

Answer 1

Ipsilateral fixed and dilated pupil - compression of ipsilateral oculomotor nerve (CN III) and parasympathetic fibers

Question 2

What does a tonsilar herniation do?

Answer 2

Fixed, midposition pupils due to disruption of both sympathetic and parasympathetic innervation

Question 3

What does a subfalcine herniation do?

Answer 3

Cingulate gyrus (just above corpus callosum) pushed underneath falx cerebri

Does not cause pupillary involvement, irregular respirations, or coma (i.e. reticular activating system compression)

Progression –> ipsilateral anterior cerebral artery compression –> contralateral leg weakness

Question 4

Mild vs moderate vs severe hypothermia

Answer 4

Mild (32-35): increased shivering

Moderate (28-32): decreased shivering

Severe (<28): coma, marked hypotension, malignant ventricular arrhythmias (e.g. fib), significant acidosis; may use internal warming with pleural or peritoneal irrigation

Question 5

What to do to test whether frostbite limb is salvageable

Answer 5

Angiography or technetium scan - identifies thrombosis that can be targeted with thrombolytics