Max had a big day today (barium study and a scheduled LP later today) so I didn't get him out of his crib. I did have a long conversation with one of his physical therapists about signs of stress in preemie infants. It turns out that there's a subtle but important distinction between preemies who are snuggling and those who are "shutting down" (a severe reaction to stress). Among the signs that your kid is shutting down: color change, grimacing, and As and Bs. All this time I thought he was just smiling at me!
We spoke to the doc who examined his barium study: no problems, and almost certainly not Hirschsprung's Disease. The slow bowel action was attributed, at worst, to his hydrocephalus. At best, it's just normal baby rhythm. The surgeon we spoke with asked about Max's head bleeds and hydrocephalus. He seemed really sad about them; I think we've made our peace with the likely consequences.
As for the incipient fluid-retention crisis, Max's sodium level was high and his protein level was low, so the kidneys were having trouble producing sufficient urine. One of Max's doctors kept talking about his BUN level. All I know about BUN I learnt from classic novel by Samuel Shem, The House of God, where Shem promulgates the nonsense law that BUN + Age = lasix dose. But I couldn't remember it and so missed my chance to impress his doctors. Oh well. Anyway, Max's age is like -0.2 years and they didn't give him lasix. The upshot is that they'll back off the supplemental sodium, increase his supplemental protein and expect his urine production to increase.
On the northern front, a head ultrasound showed a slight increase in ventricular volume, so his doctors will tap him later tonight. They will go for the standard 10 cc draw; earlier rumors of a bigger draw were simply baseless rumors.