The cranial nerves are key because they come out of the brain stem segmentally, and the big question is: is the brain stem involved? That’s why we begin with the eyes. The eyes are the secret to unconsciousness. We can’t test smell in these patients because that requires cooperation. Remember that smelling salts do not test smell; they test pain, the fifth cranial nerve. You can test everything else, but do you? You don’t have to. The eyes include cranial nerves 2, 3, 4, and 6, so you can go from 2 to 6 just by looking at the eyes. Whether the person gags or swallows when you move the tube
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