Rostrocaudal deterioration—Why thank God...?
Why thank God when comatose patients are intubated?
Recall that the kinds of coma we are dealing with arise (presumably) from masses in the head. Tumors, strokes, blood clots, hydrocephalus, whatever.
Recall the CO2 response: for increasing pA CO2, the brain's vasculature dilates and more blood gets pumped into the brain, increasing its volume. If your brain is already packed in tightly by a blood clot, and you begin to lose consciousness and hypoventilate (raising your pA CO2),
your already-insulted brain gets hit with the additional insult of increased volume. And it doesn't like that. Your neurological deterioration accelerates, often to the point of irreversibility. This can happen with truly frightening rapidity.
DO NOT LET COMATOSE PATIENTS HYPOVENTILATE: INTUBATE EARLY!
- Hypoventilation in comatose patients MUST be avoided.
- Controlled ventilation and moderate hyperventilation can protect the brain and buy significant time in an emergency situation.