Sodium (Latin: natrium) 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.
In this article:
- Signs and Symptoms
- Nursing Process
- Nursing Care Plans
- Decreased Cardiac Output
- Deficient Fluid Volume
- Excess Fluid Volume
- Ineffective Tissue Perfusion
Signs and Symptoms
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:
- Restlessness
- Agitation
- Lethargy
- Intense thirst
- Muscle cramps
- Weakness
- Postural hypotension
- Tachycardia
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, such as in the syndrome of inappropriate antidiuretic hormone (SIADH).
Clinical manifestations of hyponatremia occur because of cellular swelling. Symptoms include:
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
Once the nurse identifies nursing diagnoses for hyponatremia or hypernatremia, nursing care plans help prioritize assessments and interventions for both short and long-term goals of care. In the following section, you will find nursing care plan examples for hyponatremia and hypernatremia.
Acute Confusion
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
Related to:
- Dehydration
- Electrolyte imbalance
- Impaired metabolism
- Urinary retention
As evidenced by:
- Cognitive dysfunction
- Difficulty initiating goal-directed behavior
- Difficulty initiating purposeful behavior
- Neurobehavioral manifestations
- Psychomotor agitation
- Seizure activity
Expected outcomes:
- Patient will remain oriented to person, place, and time.
- Patient will not experience seizure activity.
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.
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.
Decreased Cardiac Output
Alterations in serum sodium levels are associated with cardiac dysfunction.
Nursing Diagnosis: Decreased Cardiac Output
Related to:
- Impaired contractility
- Increased afterload
- Increased ventricular filling
- Decreased myocardial oxygenation
As evidenced by:
- Tachycardia
- Tachypnea
- Dyspnea
- Orthopnea
- Reduced oxygen saturation
- Hypertension
- Decreased central venous pressure
- Dysrhythmia
- Fatigue
- Reduced ejection fraction
- Anxiety/restlessness
- Decreased activity tolerance
- Edema
- Crackles
- Decreased urine output
Expected outcomes:
- Patient will manifest adequate cardiac output as evidenced by the following:
- Systolic BP within 20 mmHg of baseline
- Heart rate: 60 to 100 beats/min with a regular rhythm
- Respiratory rate: 12 to 20 breaths/min
- Urine output 0.5 to 1.5 cc/kg/hour
- Patient will not experience activity intolerance.
Assessment:
1. Monitor 12-lead ECG.
Atrial fibrillation is associated with more than 30% of patients with hyponatremia, and concurrence of the two conditions strongly predicts poor clinical outcomes among patients with heart failure. ECG provides information about dysrhythmias and the development of myocardial ischemia that causes decreased cardiac output.
2. Assess blood pressure.
Excess sodium intake increases blood pressure, a common cause of hypertension and cardiovascular conditions.
Interventions:
1. Administer medications as ordered.
Heart failure is frequently associated with hyponatremia. The cornerstone of treatment includes a combination of angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, and diuretics to reduce cardiac workload and fluid retention.
2. Assist in diagnostic modalities. Review laboratory results.
- 12 lead ECG: a first-line diagnostic tool for diagnosing arrhythmias.
- Cardiac troponins: elevated I and T troponin levels are significant markers of myocardial damage.
- Pro-BNP: assesses the severity of heart failure.
- Imaging tests, i.e., echocardiography and MRI: provide a practical assessment of myocardial structural and functional abnormalities.
3. Educate on sodium-restricted, low-saturated fat meals.
Sodium-restricted diets help decrease fluid volume excess. Excessive sodium can lead to hypertension, renal impairment, and cardiac structural abnormalities, decreasing cardiac output. Low-saturated fat diets help reduce coronary artery disease.
4. Have the patient weigh themselves at the same time daily.
Alterations in weight can provide sensitive information regarding fluid retention. Instruct the patient to weigh themselves at the same time each day using the same scale.
Deficient Fluid Volume
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
Related to:
- Hypernatremia
- Hyponatremia
- Active fluid volume loss
- Compromised regulatory mechanisms
As evidenced by:
- Alteration in skin turgor
- Decrease in blood pressure
- Decrease in urine output
- Thirst
- Weakness
- Elevated hematocrit
Expected outcomes:
- Patient will maintain normal hydration status as evidenced by urine output and concentration within normal limits.
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.
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
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
Related to:
- 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
- Oliguria
- Edema
- Weight gain over a short period
Expected outcomes:
- Patient will be free of edema, abnormal lung sounds, and maintain normal intake and output.
- Patient will identify causes of excess fluid volume and resulting hyponatremia.
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.
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.
Ineffective Tissue Perfusion
Alterations in sodium can cause vasoconstriction and increased or decreased extracellular volume, affecting organ perfusion.
Nursing Diagnosis: Ineffective Tissue Perfusion
Related to:
- Impaired oxygen transport
- Interruption in blood flow
- Altered sodium levels
- Hypervolemia
- Hypovolemia
As evidenced by:
- Confusion
- Muscle cramps
- Headache
- Flushed skin
- Hypertension
- Orthostatic hypotension
- Decreased urine output
- Dry mucous membranes
- Poor skin turgor
- Peripheral edema
Expected outcomes:
- Patient will maintain optimal tissue perfusion as evidenced by the following:
- Warm and dry extremities
- Moist mucous membranes
- Absence of pitting edema
- Patient will not experience any changes in the level of consciousness.
- Patient will demonstrate a urine output of 0.5 to 1.5 cc/kg/hour.
Assessment:
1. Monitor neurological status.
The brain is the principal organ affected by alterations in serum sodium levels. Neurological complications include cerebral edema and increased intracranial pressure impairing cerebral tissue perfusion. Monitor closely for changes in cognition, consciousness, and involuntary muscle control.
2. Assess for edema in the extremities.
Hypervolemic hyponatremia manifests peripheral edema due to excessive water retention. Pitting edema on a scale of 1-4 describes the severity.
Interventions:
1. Administer IV fluid as ordered.
Sodium-containing IV solutions may aid in supplementing sodium depletion in hyponatremia.
2. Administer diuretics as ordered.
In cases of hypernatremia, thiazide diuretics promote sodium excretion in the urine by preventing sodium reabsorption in the distal convoluted tubule. Loop diuretics like furosemide reduce sodium reabsorption in the loop of Henle.
3. Collect 24-hour urine.
This test allows for the evaluation of sodium and other chemicals in the urine. Alterations in urine sodium can help identify possible causes of kidney disease.
4. Educate on strategies to improve tissue perfusion related to hypo/hypernatremia and hypo/hypervolemia.
- Move slowly when changing positions
- Maintain moderate physical activity
- Hydrate appropriately when outside in the sun for extended periods
- Avoid activities requiring prolonged sitting (long car/plane rides)
- Wear compression stockings to promote peripheral blood circulation
- Elevate the legs above the level of the heart to increase venous return and alleviate peripheral edema
References
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