Janet,  there certainly are concerns with concentrating formula beyond the
recommended levels on the label. Electrolyte balance can be thrown way off
track. It seems to me this would be of great concern for a baby with cardiac
problems.  In addition to Cindy's recommendations as possible alternatives
perhaps fortification with polycose might work.  It also needs to be
considered that premature formula has increased concentrations of many
things.  I don't know if the baby needs or can handle additional fat,
protein, micro nutrients, carbohydrates or just needs calories.  The
cardiologist should be in on this decision along with the mom and
pediatrician.

But, before switching to any commercial concoction consider using the
expressed breastmilk, preferably in a supplemental nursing device to
increase intake.  This is the type of situation where the large bore tubing
may be the best choice.  I've read of using both tubings of the SNS at once
but haven't done it myself.  Speed of flow can also be increased by opening
the opposite tubing, warming the milk and/or raising the bottle.  Watch out
not to overwhelm the baby with too fast a flow too.

If there is adequate expressed breastmilk consider fractionating it to use
more of the higher fat portion, either by switching pumping containers mid
session or by letting the cream rise and pouring off that portion of stored
milk.  Freeze the lowfat portions for use in cereal later.

It seems time to get this baby to surgery but I'm sure that is a delicate
balancing act.  Breastfeeding is an important factor in keeping THIS baby
well and the dangers of using formula should be part of the equation of
waiting for growth vs surgery on a smaller baby.

Remind mom to protect her milk supply with pumping after feeds until baby is
well and vigorous again. She will probably need to do this for at least a
week or two after surgery.

Carla