From the Guidelines
Hypernatremia typically presents with signs and symptoms such as intense thirst, dry mucous membranes, flushed skin, and decreased skin turgor, along with neurological symptoms like irritability, restlessness, lethargy, confusion, muscle twitching, seizures, and in severe cases, coma. These manifestations are a result of the body's response to elevated sodium levels in the blood, which causes water to move out of cells into the bloodstream due to osmotic pressure, leading to cellular dehydration 1. The severity of symptoms typically correlates with both the degree of sodium elevation and the rapidity of onset, with acute rises causing more dramatic presentations than gradual increases.
Key Symptoms
- Intense thirst
- Dry mucous membranes
- Flushed skin
- Decreased skin turgor
- Neurological symptoms:
- Irritability
- Restlessness
- Lethargy
- Confusion
- Muscle twitching
- Seizures
- Coma (in severe cases)
It is crucial to recognize these symptoms for prompt diagnosis and treatment to prevent serious neurological complications, especially considering that a rapid correction of hypernatremia may induce cerebral edema, seizures, and neurological injury 1. The management should be based on the etiology, including assessment of the patient's intravascular volume and hydration status, and a reduction rate of 10-15 mmol/L/24h is recommended for correction 1.
Patient Considerations
- Elderly patients and infants may present atypically, with subtle changes in mental status being the only initial sign.
- Polyuria may occur as the kidneys attempt to excrete excess sodium, potentially worsening dehydration.
- The evidence from 1 highlights the importance of careful management to avoid complications, particularly in vulnerable populations such as very low birth weight infants (VLBWI).
From the Research
Signs and Symptoms of Hypernatremia
The signs and symptoms of hypernatremia (elevated sodium levels) can vary depending on the severity of the condition. Some common symptoms include:
- Confusion and altered mental status 2, 3, 4
- Coma 2, 3
- Pronounced thirst (in awake patients) 2
- Anorexia, muscle weakness, restlessness, nausea, and vomiting 3
- Lethargy, irritability, stupor 3
- Seizures (in severe cases) 3
- Cerebral bleeding and subarachnoid hemorrhage (in cases of acute brain shrinkage) 3
Severity of Hypernatremia
The severity of hypernatremia can be classified based on the serum sodium concentration:
- Mild hypernatremia: often caused by dehydration resulting from an impaired thirst mechanism or lack of access to water 5
- Severe hypernatremia: can cause serious symptoms such as delirium, confusion, impaired consciousness, and coma 5, 3
Clinical Presentation
The clinical presentation of hypernatremia can vary depending on the underlying cause and the severity of the condition. Patients may be pauci-symptomatic to comatose 4. The clinical presentation is often characterized by a central nervous system dysfunction and pronounced thirst (in awake patients) 2.
Diagnosis and Treatment
Diagnosis and treatment of hypernatremia involve identifying the underlying cause and correcting the fluid deficit 5, 6. Treatment starts with addressing the underlying etiology and correcting the fluid deficit. When sodium is severely elevated, patients are symptomatic, or intravenous fluids are required, hypotonic fluid replacement is necessary 5. Close laboratory controls are important to avoid rapid changes in serum sodium concentration, which can have deleterious consequences (osmotic demyelination syndrome) 2, 3, 4.