From the Guidelines
The correction rate for severe hypernatremia should not exceed 8 mmol/l/day. This recommendation is based on the most recent and highest quality study available, which emphasizes the importance of avoiding a decrease in serum sodium above 8 mmol/l/day to prevent neurological complications 1. When managing severe hypernatremia, it is crucial to consider the patient's volume status, sodium level, and estimated total body water deficit to determine the appropriate fluid choice and rate.
Key Considerations
- The use of hypotonic fluids such as 5% dextrose in water (D5W), 0.45% saline, or occasionally 0.9% saline may be necessary, depending on the patient's volume status.
- Frequent monitoring of serum sodium levels (every 2-4 hours initially) is essential to adjust therapy accordingly and prevent complications such as cerebral edema.
- The underlying cause of hypernatremia, whether it's excessive water loss, inadequate water intake, or iatrogenic sodium administration, must be addressed simultaneously.
- In patients with chronic hypernatremia (developing over days), even slower correction may be warranted as the brain has had time to adapt to the hyperosmolar state.
Treatment Approach
- Calculate the initial rate of fluid administration to avoid a decrease in serum sodium above 8 mmol/l/day, as recommended by the international expert consensus statement 1.
- Consider the patient's individual needs and adjust the treatment approach accordingly, taking into account factors such as age, comorbidities, and underlying cause of hypernatremia.
- Prioritize the prevention of neurological complications, such as cerebral edema and seizures, which can be fatal if not properly managed.
From the Research
Correction Rate for Severe Hypernatremia
The correction rate for severe hypernatremia is a critical aspect of treatment, as both rapid and slow correction rates can have significant implications for patient outcomes.
- The recommended correction rate is ≤0.5 mEq/L/hr 2, although some studies suggest that a rapid correction rate may be indicated in acute cases 3.
- A study published in 2011 found that 90% of patients received the recommended <0.5 mEq/L/hr serum Na(+) correction rate, but hypernatremia was corrected only in 27% of patients after 72 hours of treatment 2.
- Another study published in 2019 found that the difference in in-hospital 30-day mortality proportion between rapid (>0.5 mmol/L per hour) and slower (≤0.5 mmol/L per hour) correction rates were not significant in patients with hypernatremia at admission or in patients with hospital-acquired hypernatremia 4.
Factors Influencing Correction Rate
Several factors can influence the correction rate for severe hypernatremia, including:
- The duration of hypernatremia, with chronic cases potentially requiring slower correction rates to avoid neurological complications 5.
- The rate of development of hypernatremia, with acute cases potentially requiring rapid correction rates to prevent severe neurologic damage or death 5.
- The use of hypertonic or isotonic saline, with or without the addition of furosemide or an osmotic diuretic agent, which can impact the correction rate and patient outcomes 5.
Patient Outcomes
Patient outcomes can be significantly impacted by the correction rate for severe hypernatremia, with both rapid and slow correction rates associated with risks and benefits.
- A study published in 2019 found that rapid correction of hypernatremia was not 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 4.
- Another study published in 2000 reported a case of severe hypernatremia with survival, where the patient underwent rapid correction of serum sodium concentration using isotonic solution 6.