What is low sodium? Another look.

A patient had "low sodium"  He was treated by adding dietary salt--despite Hx of cardiac problems and edema from recent surgery.

Was it really low sodium?  Yes, in salt concentration.  Serum Na was 124.  

Was it really low sodium?  No, in salt content.   Edema had added 14 Kg.  Each Kg held 124 meq or 10 gm.  His salt supply was high by 10X14 gm = 140 gm!  Since the normal salt content is about 140 gm in vascular plus interstitial spaces,  He had doubled his salt content.  Why add salt?

Better give 25% albumin to shift saline from hurtful, squeezing edema.  Albumin pulls edema into vessels where it is needed to improve renal blood flow.  Better blood flow releases salt to the toilet, releases squeeze.  Harvests salt from content to improve concentration.