>  Another intersting note is that he has now turned a  mild shade of
>grey/blue three times while nursing -- comes up his body over his head/face
>then receeds to pink/yellow quite rapidly, baby never stops nursing.

Anne,
I had a somewhat similar case that I posted to Lactnet 15 mos ago.  Baby
changed colors during or after nursing, had lost weight, appeared to
latch correctly, but with test weights, wasn't taking in enough milk.  I
immediately sent a MD report noting the color changes, and the concerned
MD immediately had the baby admitted for observation. During the next
couple of days her suck deteriorated greatly and she became apneic; at
the end of the week, she spontaneously improved again, though it took a
long time to get her breastfeeding back up to speed.  Never had a
definitive diagnosis, despite cardiology work-up. Suspected a possible
partial enzyme deficiency...........   I'd say, notify ped immediately!

-Lisa Marasco, BA, IBCLC