From the Guidelines
Hyponatremia symptoms include headache, nausea, vomiting, confusion, fatigue, irritability, muscle weakness, cramps, and seizures in severe cases, and it is crucial to seek medical attention immediately if these symptoms occur, especially after excessive fluid intake or while taking medications that can affect sodium levels. Early symptoms are often subtle and nonspecific, such as feeling unwell or experiencing mild cognitive changes. As sodium levels drop further, neurological symptoms become more prominent due to brain cell swelling caused by water moving into cells. Acute hyponatremia (developing over less than 48 hours) typically causes more severe symptoms than chronic hyponatremia, as the brain hasn't had time to adapt to the low sodium levels. Very severe hyponatremia can lead to brain herniation, coma, and death if not treated promptly. According to the most recent guidelines, mild hyponatremia (Na 126-135 mEq/L) in cirrhosis without symptoms does not require specific management apart from monitoring and water restriction 1.
Some key points to consider in the management of hyponatremia include:
- Water restriction to 1,000 mL/day and cessation of diuretics is recommended in the management of moderate hyponatremia (120-125 mEq/L) 1
- A more severe restriction of water intake with albumin infusion is recommended for severe hyponatremia (<120 mEq/L) 1
- The use of vasopressin receptor antagonists in cirrhosis can raise serum sodium during treatment, but they should be used with caution only for a short term (≤30 days) 1
- The use of hypertonic saline is reserved for short-term treatment of patients with symptomatic or severe hyponatremia or those with imminent liver transplant (LT) 1
Risk factors for hyponatremia include certain medications (diuretics, antidepressants, antipsychotics), excessive water intake, heart failure, kidney disease, liver disease, and endocrine disorders like SIADH or adrenal insufficiency. It is essential to correct chronic hyponatremia at a goal rate of increase of serum (Na) of 4-6 mEq/L per 24-hour period, not to exceed 8 mEq/L per 24-hour period to ameliorate the risk of osmotic demyelination syndrome (ODS) 1. Severe hyponatremia (<120 mEq/L) at the time of liver transplant increases the risk of ODS, and multidisciplinary coordinated care may mitigate this risk 1.
From the Research
Hyponatremia Symptoms
- Hyponatremia is defined by a serum sodium level of less than 135 mEq/L and can cause a range of symptoms from mild and nonspecific to severe and life-threatening 2
- Symptoms of hyponatremia include weakness, nausea, seizures, coma, cognitive impairment, gait disturbances, and increased rates of falls and fractures 2
- The severity of symptoms depends on the rapidity of development, duration, and severity of hyponatremia 2
- Mild chronic hyponatremia is associated with increased risk of falls and fractures, and hyponatremia is a secondary cause of osteoporosis 2
Clinical Presentation
- Hyponatremia can present with a wide spectrum of clinical symptoms, from mild to severe or even life-threatening 3
- Symptoms may be mistakenly attributed to other conditions, such as heart failure 4
- Clinical evidence suggests that hyponatremia is associated with increased mortality, morbidity, and length of hospital stay 3
Diagnosis and Treatment
- Diagnosis of hyponatremia involves determining the serum osmolality and volume status of the patient 5
- Treatment should be initiated to correct the serum sodium by 8 to 12 mEq/L within the first 24 hours 5
- Arginine vasopressin (AVP) antagonists, such as conivaptan and tolvaptan, are effective in treating hypervolemic and euvolemic hyponatremia 5
- Tolvaptan is a selective V2-receptor antagonist that can be used to treat hyponatremia in patients with heart failure 6, 4