Sodium is an electrolyte that helps maintain the volume and concentration of extracellular fluid and affects water distribution between intracellular fluid and extracellular fluid. It is vital in the generation and transmission of nerve impulses, muscle contractility, and the regulation of acid-base balance.
The ratio of sodium to water is reflected by the serum sodium level. Changes in the serum sodium level can indicate primary sodium imbalance, primary water imbalance, or both.
Hypernatremia or elevated serum sodium greater than 145 mEq/L occurs when there is excess water loss, inadequate water intake, or excess sodium gain. This condition causes hyperosmolarity, making the patient excessively thirsty.
Signs and symptoms of hypernatremia occur due to the shifting of water out of the cells causing cell shrinkage and dehydration. Symptoms include:
- Intense thirst
- Muscle cramps
- Postural hypotension
Hyponatremia or low serum sodium of less than 135 mEq/L results from a loss of sodium-containing fluids often caused by diarrhea, vomiting, and draining wounds. This condition can also result from excess water in relation to sodium levels like the inappropriate use of sodium-free IV fluids.
Clinical manifestations of hyponatremia occur because of cellular swelling. Symptoms include:
The Nursing Process
The management of hypernatremia and hyponatremia will depend on the underlying cause. Hypernatremia management will include fluid replacement either orally or through intravenous access and diuretics to promote sodium excretion. Hyponatremia management involves fluid replacement using sodium-containing fluids, increased oral intake, and other salt-replacing medications.
Nurses are responsible for monitoring sodium levels and identifying clinical manifestations that can indicate further complications of underlying medical conditions. Electrolyte management requires serious assessment and delicate treatment. Nurses can educate patients and families on the important role electrolytes play in the body and how to prevent future imbalances.
Nursing Care Plans Related to Hypernatremia and Hyponatremia
Deficient Fluid Volume Care Plan
Either hyponatremia or hypernatremia occurs when there are severe deficits in fluid volume, depending on the ratio of sodium to water.
Nursing Diagnosis: Deficient Fluid Volume
- Active fluid volume loss
- Compromised regulatory mechanisms
As evidenced by:
- Alteration in skin turgor
- Decrease in blood pressure
- Decrease in urine output
- Elevated hematocrit
- The patient will maintain normal hydration status as evidenced by urine output and concentration within normal limits
Deficient Fluid Volume Assessment
1. Assess for signs of hypovolemia.
Early signs of hypovolemia include thirst, headaches, restlessness, and inability to concentrate. Late signs include thready pulses, cold and clammy skin, oliguria, and confusion. These symptoms occur after the body has attempted to compensate for the loss of fluids.
2. Assess factors that contribute to fluid volume deficit.
Factors like vomiting, diarrhea, diuretic drug therapy, fever, hemorrhage, and decreased oral fluid intake can influence hyponatremia from deficient fluid volume.
Deficient Fluid Volume Interventions
1. Monitor intake and output accurately.
Ensure a balance between oral and IV intake compared with urine output. Inspect urine clarity and concentration.
2. Administer IV fluids as indicated.
5% dextrose or 0.45% normal saline can be used to fluid volume deficit without worsening hypernatremia.
3. Administer medications as ordered.
Antidiarrheals or antiemetics may be ordered as appropriate to treat symptoms of the underlying cause.
4. Encourage salt-containing foods and fluids.
Encourage free water as applicable. Encourage soups, broths, and Pedialyte to enhance fluid intake and correct hyponatremia.
Excess Fluid Volume Care Plan
Hyponatremia can occur with excess fluid intake without solute replacement and when there is excessive water intake versus water excretion in the kidneys. This results in sodium concentration in the blood being diluted.
Nursing Diagnosis: Excess Fluid Volume
- Compromised regulatory mechanisms (SIADH)
- Excessive fluid intake
- Deviations affecting fluid elimination
- Excess sodium intake
As evidenced by:
- Altered mental status
- Altered urine-specific gravity
- Intake exceeds output
- Weight gain over a short period
- The patient will be free of edema, abnormal lung sounds, and maintain normal intake and output
- The patient will identify causes of excess fluid volume and resulting hyponatremia
Excess Fluid Volume Assessment
1. Assess signs of excess fluid volume.
Anasarca can occur when the kidneys are unable to excrete excess fluid.
2. Monitor lab values.
Monitor kidney function, albumin, electrolytes, and urine specific gravity and osmolality to assess for imbalances and underlying issues.
Excess Fluid Volume Interventions
1. Monitor lung sounds.
Excess fluid volume can cause acute pulmonary edema as an underlying cause.
2. Restrict fluids.
Excess fluid volume can be treated by restricting oral and IV fluid intake. Most restrictions are 1-1.5 L.
3. Restrict diuretic medications as indicated.
Diuretics rid the body of water which is useful in treating fluid volume overload but may perpetuate hyponatremia.
4. Administer salt tablets.
Patients with severe hyponatremia may require sodium chloride tablets which are essentially salt tablets to increase sodium levels.
Acute Confusion Care Plan
Both hypernatremia and hyponatremia manifest neurologic symptoms. Severe hyponatremia (<115 mEq/L) can cause confusion, seizures, coma, and death. Hypernatremia can cause lethargy, personality changes, and confusion.
Nursing Diagnosis: Acute Confusion
As evidenced by:
- Cognitive dysfunction
- Difficulty initiating goal-directed behavior
- Difficulty initiating purposeful behavior
- Neurobehavioral manifestations
- Psychomotor agitation
- Seizure activity
- The patient will remain oriented to person, place, and time
- The patient will not experience seizure activity
Acute Confusion Assessment
1. Assess the patient’s mental status.
Establishing the patient’s baseline mental status and performing frequent cognitive assessments can help identify subtle changes in cognition and behavior.
2. Assess risk factors and underlying conditions that contribute to an altered mental state.
Identifying risks and possible causes helps formulate a care plan that will prevent confusion and changes in mentation.
Acute Confusion Interventions
1. Assist in correcting fluid and electrolyte imbalance.
Fluid and electrolyte imbalances can cause acute confusion. Addressing and correcting these imbalances will help resolve acute confusion.
2. Constantly reorient the patient.
Confusion can cause agitation and present a safety issue. Continually orient the patient to person, place, and situation.
3. Provide a calm environment.
Prevent overstimulating the patient and offer plenty of rest periods with minimal interruptions.
4. Implement seizure precautions.
Severely low sodium levels can cause seizures due to the shift of water into brain cells causing cerebral swelling. Patients at risk for seizures should have safety precautions in place.
References and Sources
- Diagnosis and Management of Sodium Disorders: Hyponatremia and Hypernatremia. American Family Physician. Am Fam Physician. 2015;91(5):299-307. MICHAEL M. BRAUN, DO, CRAIG H. BARSTOW, MD, AND NATASHA J. PYZOCHA, DO. From: https://www.aafp.org/pubs/afp/issues/2015/0301/p299.html
- Difference Between Hypernatremia and Hyponatremia. WebMD. Dan Brennan, MD. Updated May 16, 2021. From: https://www.webmd.com/a-to-z-guides/difference-between-hypernatremia-hyponatremia
- Friedler, R. M., Koffler, A., & Kurokawa, K. (1977). Hyponatremia and hypernatremia. Clinical nephrology, 7(4), 163–172. From: https://pubmed.ncbi.nlm.nih.gov/870270/