Overview
Introduction
A serum sodium result is a concentration, not a direct measure of the body's total sodium.
A serum sodium result is a concentration, not a direct measure of the body's total sodium. A low value may reflect excess free water, sodium loss with volume depletion, or water retention in an edematous patient. A high value usually signals too little free water relative to solute. Pair the result with neurological status, symptom timing, volume status, renal function, and the trend before deciding what it means or what fluid is appropriate.