Wednesday, November 26, 2008

The ABDs of the NICU

In the NICU, babies are said to have "A"s and "B"s. In addition, I think they should also be said to have "D"s.

A is for apnea, babies' disquieting habit of forgetting to breathe. Max, and many other preemies, are reminded to breathe by being giving IV caffeine and having air blown at their face (hence Max's continued use of a nasal canula). Many a nurse and doctor has taken us aside to explain that "caffeine is a stimulant". Seven years of grad school taught us that, thanks very much. But if the idea of giving your infant a big cup of coffee every morning strikes you as odd, welcome to the NICU.

B is for bradycardia; in infants, when the heart rate falls below 100 beats per minute. There doesn't seem to be a good explanation for why preemies have bradycardia episodes (or "bradies"), but it seems related to their underdeveloped brains; the episodes are correlated with apneas as well. Usually, Max comes out of apnea/bradycardia episodes on his own, or with gentle prompting.

D is for desaturation; NICU patients have a red light bulb taped to their feet. This measures (sort of) the oxygen saturation of the tissues near the surface of the skin as far as I can tell. This saturation can drop because the infant is experiencing an "A" or "B", or simply for no reason at all that I can divine. Interestingly, Ada's sats were pretty good until the end, but direct measurement of the oxygen content of her blood showed severe oxygen deprivation, so the sat monitor isn't perfect.