How do you manage fluids in the ELBW - 500g infant?
We start at 100 ml/kg/d and increase by ~20 ml/kg daily.
Despite plastic wrap in DR, humidified incubators, etc we often have significant hypernatremia usually by 24 hours, sometimes > 150, sometimes > 160.
Is this a sodium problem or a water problem or (probably) both?
These little guys have lots of transepidermal water loss especially in the first 2 days. They also get Na Acetate via UAC giving sometimes 1.5-2 mEq/kg/d of Na in that first day when the kidneys (from what I read) can excrete free water but cannot filter an excess sodium load well. And some lit suggests retention of birth weight (or not having the physiologic 10-15% wt loss in ELBW) is associated with BPD, PDA, etc.
When would you give normal saline bolus for hypernatremia considering that the kidneys may not be able to excrete excess Na load? Or would you just continue to increase free water via non-Na fluids to replace the insensible losses and restore intravascular volume. How high would you go with total fluids? 180-200 ml/kg/d in the first 2-3 days of life? Higher? Any experience with sterile water drip via orogastric tube for ELBW with hypernatremia?