From the Guidelines
The treatment for hypernatremia should focus on correcting the underlying cause while safely lowering serum sodium levels, with a recommended reduction rate of 10-15 mmol/L/24 hours to prevent cerebral edema and neurological injury. This approach is crucial in managing hypernatremia, especially in vulnerable populations such as very low birth weight infants (VLBWI), where incorrect replacement of transepidermal water loss, inadequate water intake, or excessive sodium intake can lead to hypernatremia 1.
When addressing hypernatremia, it is essential to assess the infant's intravascular volume and hydration status to guide therapeutic measures. In cases of symptomatic hypovolemia, plasma volume should be replaced, and the use of hypotonic fluids may be considered to help correct the sodium imbalance. The goal is to provide a balanced approach to fluid replacement, avoiding rapid correction that can induce cerebral edema, seizures, and neurological injury, as highlighted in the guidelines for pediatric parenteral nutrition 1.
Key considerations in the treatment of hypernatremia include:
- Assessing the underlying cause to guide specific therapeutic interventions
- Monitoring serum sodium levels, urine output, and mental status closely during treatment
- Avoiding rapid correction of sodium levels to prevent complications such as cerebral edema
- Using hypotonic fluids for fluid replacement, calculated based on the total body water deficit
- Considering the use of loop diuretics in cases of hypervolemic hypernatremia, and desmopressin (DDAVP) in cases of diabetes insipidus causing hypernatremia, although these specific treatments are not directly mentioned in the provided evidence, they are part of the general approach to managing hypernatremia based on its cause.
The primary evidence supporting the cautious approach to correcting hypernatremia comes from guidelines that emphasize the importance of gradual correction to prevent neurological complications 1. This principle guides the management of hypernatremia in clinical practice, prioritizing the safety and well-being of the patient by minimizing the risk of adverse outcomes associated with rapid sodium level corrections.
From the Research
Treatment for Hypernatremia
- Hypernatremia is a common electrolyte disorder that reflects an imbalance in the water balance of the body, often resulting from an increased loss of free water compared to sodium excretion 2.
- The treatment of hypernatremia usually involves replacing the absolute or relative loss of free water by hypotonic infusions, or in case of diabetes insipidus, by application of Desmopressin (Minirin) 2.
- Rapid changes in serum sodium concentration may have deleterious consequences, such as osmotic demyelination syndrome, therefore preexisting hypernatremia (>48h) should not be reduced by more than 8-10 mmol/l/day 2.
- For acute hypernatremia (< 24 hours), hemodialysis is an effective option to rapidly normalize the serum sodium levels 2.
Management of Central Diabetes Insipidus
- Central diabetes insipidus can be managed with desmopressin (DDAVP), which is the first line agent for outpatient treatment 3.
- A protocol using dilute vasopressin bolus can be an alternative for managing acute, central diabetes insipidus postoperatively, particularly in setting of hypovolemic shock resulting in a consistent control of serum sodium 4.
- A rapidly titratable low-dose continuous intravenous arginine vasopressin infusion can be used to maintain eunatremia in patients with central diabetes insipidus during periods of obligate fluid intake, such as during chemotherapy 5.
Correction Rate of Hypernatremia
- There is no clear evidence that rapid correction of hypernatremia is associated with a higher risk for mortality, seizure, alteration of consciousness, and/or cerebral edema in critically ill adult patients with either admission or hospital-acquired hypernatremia 6.
- The optimal rate of hypernatremia correction in hospitalized adults is unclear, but some studies suggest a reduction rate not to exceed 0.5 mmol/L per hour 6.