Question

what is the pathophysciology, Medications, signs and symptoms, Labs/diagnosis and nursing intervention of Hypernatremia and Hyponatremia

Answer 1

Ans) Hyponatremia and hypernatremia are common findings in the inpatient and outpatient settings. Sodium disorders are associated with an increased risk of morbidity and mortality. Plasma osmolality plays a critical role in the pathophysiology and treatment of sodium disorders. Hyponatremia and hypernatremia are classified based on volume status (hypovolemia, euvolemia, and hypervolemia). Sodium disorders are diagnosed by findings from the history, physical examination, laboratory studies, and evaluation of volume status. Treatment is based on symptoms and underlying causes. In general, hyponatremia is treated with fluid restriction (in the setting of euvolemia), isotonic saline (in hypovolemia), and diuresis (in hypervolemia). A combination of these therapies may be needed based on the presentation. Hypertonic saline is used to treat severe symptomatic hyponatremia. Medications such as vaptans may have a role in the treatment of euvolemic and hypervolemic hyponatremia. The treatment of hypernatremia involves correcting the underlying cause and correcting the free water deficit.

- Etiology and Pathophysiology:

The most common classification system for hyponatremia is based on volume status: hypovolemic (decreased total body water with greater decrease in sodium level), euvolemic (increased total body water with normal sodium level), and hypervolemic (increased total body water compared with sodium).

Plasma osmolality has a role in the pathophysiology of hyponatremia. Osmolality refers to the total concentration of solutes in water. Effective osmolality is the osmotic gradient created by solutes that do not cross the cell membrane. Effective osmolality determines the osmotic pressure and the flow of water. Plasma osmolality is maintained by strict regulation of the arginine vasopressin (also called antidiuretic hormone [ADH]) system and thirst. If plasma osmolality increases, ADH is secreted and water is retained by the kidneys, thus decreasing serum osmolality. If plasma osmolality decreases, ADH also decreases, resulting in diuresis of free water and a return to homeostasis.

Diagnostic Approach to Hyponatremia:

- Symptoms of hyponatremia depend on its severity and on the rate of sodium decline. Gradual decreases in sodium usually result in minimal symptoms, whereas rapid decreases can result in severe symptoms. Polydipsia, muscle cramps, headaches, falls, confusion, altered mental status, obtundation, coma, and status epilepticus may indicate the need for acute intervention. Most patients with hyponatremia are asymptomatic, and hyponatremia is noted incidentally. Volume status should be assessed to help determine the underlying cause.

Nursing Intervention: Hyponatremia

- Keep in mind that misuse of hypertonic saline can be extremely dangerous, so it should be administered cautiously.

- A possible result of correcting hyponatremia too rapidly is osmotic demyelination syndrome, which involves destruction of the myelin sheath of axons in the brain stem. This syndrome can cause severe brain damage and death.

- Closely monitor intake and output. Assess for changes in level of consciousness and monitor for seizure activity. Institute patient safety measures and monitor serum electrolyte levels and urine and serum osmolality as indicated.

- Educate the patient and family about the role of sodium in the body and what a low blood level means. Teach signs and symptoms of hyponatremia and when to notify the healthcare provider. If fluid intake is restricted, tell the patient how much water he or she can drink and formulate a plan for spreading out intake during the day. Ask the patient to keep track of what he or she drinks and to let you know so you can document oral intake accurately.

Nursing Intervention: Hypernatremia

- Monitor patients for worsening hypokalemia as well as signs and symptoms of hyperkalemia during replacement therapy.

- Monitor vital signs frequently and carefully assess patients on digoxin for signs of toxicity.

- Instruct the patient and family to inform the staff of muscle pain and weakness, and to call for assistance if the patient develops chest discomfort or palpitations. Before discharge, teach the patient about foods that are high in potassium, but caution him not to take potassium supplements unless his healthcare provider recommends it. If a potassium supplement is prescribed, teach the patient how to take it. Warn the patient not to alter the dose independently.