Camille,
You posted that mom get in at least 8 feedings. Is that what the average is?
I would recommend increasing that to at least 10-12.
Has the baby been evaluated for any medical problems; like an infection,
cardiac problem, ect. I don't believe her past surgery would change how the
hind milk comes down in a feeding. It sound like this baby is either too
tired or not compinsating and therefore shuts down.(IMHO)
Good luck.
Ann Perry RN IBCLC