Hypervolaemic hyponatraemia

• clinically detectable increased ECF volume plus hyponatraemia - generally reflects hypervolaemia from some degree of body Na+ excess
• hyponatraemia with ECF volume excess can arise in a variety of diseases
  • causes of hypervolaemic hyponatraemia include:
    • CHF
    • liver cirrhosis
    • nephrotic syndrome
    • renal failure
    • excessive water intake
  • volume excess is generally diagnosed clinically from the history, physical examination and laboratory results
    • patients with clinical signs of volume overload (subcutaneous oedema, ascites, pulmonary oedema)
      • should be considered to have hypervolaemia unless there are alternative explanations for these findings

Reference:

1. Adrogué HJ, Tucker BM, Madias NE. Diagnosis and management of hyponatremia: a review. JAMA. 2022 Jul 19;328(3):280-91