Cerebral Salt Wasting

Cerebral Salt Wasting

David Ray Velez, MD

Table of Contents

Definition
Diagnosis
Treatment

See Also:
*Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH)

Definition

Definition: Excessive Urinary Sodium Loss and Subsequent Dehydration due to Central Nervous System (CNS) Disease

Some Consider Cerebral Salt Wasting to Be a Form of Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH) Rather than a Distinct Entity (Debated)

Pathophysiology

  • Pathophysiology is Poorly Understood
  • Brain Releases BNP After Injury – BNP Inhibits Sodium Reabsorption and Renin Release
  • Injured Sympathetic Nervous System – Cannot Promote Sodium Reabsorption or Stimulate Renin Release

Diagnosis

Presentation

  • Hyponatremia
  • Increased Urine Output (UOP)
  • Hypovolemia
  • Symptoms:
    • May Be Asymptomatic
    • Delirium
    • Confusion
    • Seizures

Laboratory Findings

  • Decreased Serum Sodium and Osmolality
  • Increased Urine Sodium and Osmolality

Differentiate from SIADH: Increased Urine Output (UOP) and Hypovolemia

Treatment

Treat Any Underlying Causes

Primary Treatment: Volume Resuscitation

  • Mild-Moderate Symptoms: Normal Saline (NS)
  • Severe Symptoms: Hypertonic (3%) Saline

Additional Treatment Options

  • Oral Salt Tabs
  • Fludrocortisone