Which rationale supports the nurses assessment of a patients magnesium level

In order to function properly, the body requires several electrolytes, one of which is potassium. The majority of potassium is stored in the intracellular compartment. While some can be found in the bones, liver, and red blood cells, 98% is found in the muscle cells. Potassium regulates fluid and facilitates muscular contraction and nerve activity. It is also responsible for keeping the heartbeat regular and promotes the movement of nutrients into and waste out of the cells.

The normal blood potassium level is 3.5 – 5.0 mEq/L. Imbalances in blood potassium levels are referred to as hypokalemia and hyperkalemia.

• Hypokalemia – serum potassium level < 3.5 mEq/L (3.5 mmol/L) 
• Hyperkalemia – serum potassium level > 5.0 mEq/L (5.0 mmol/L)

Possible causes of hypokalemia include the following:

• Potassium loss due to:
  • Excessive use of potassium-wasting diuretics
  • Increased production of aldosterone (water and salt regulating hormone) – (such as in Cushing’s syndrome)
  • Vomiting, diarrhea
  • Wound drainage 
  • Prolonged nasogastric suction
  • Excessive diaphoresis
  • Kidney disease impairing the reabsorption of potassium
• Poor potassium intake such as through eating disorders
• Potassium movement from extracellular to intracellular fluid due to:
  • Alkalosis
  • Hyperinsulinism
• Serum potassium dilution due to:
  • Water intoxication
  • IV therapy with potassium-deficient solutions

Possible causes of hyperkalemia include the following:

• Excessive potassium intake
• Rapid infusion of potassium-containing IV solutions

• Decreased potassium excretion
  • Potassium-sparing diuretics
  • Kidney disease
  • Adrenal insufficiency (such as in Addison’s disease)
• Potassium movement from intracellular to the extracellular fluid
  • Tissue damage (burns)
  • Acidosis
  • Hyperuricemia
  • Hypercatabolism

Signs and symptoms of potassium imbalance include:

• Hypokalemia
  • Thready, weak, and irregular pulses 
  • Muscle weakness, leg cramps, deep tendon hyporeflexia, and paresthesias 
  • Nausea, vomiting, constipation, and abdominal distention
  • ECG changes: ST depression, inverted T waves, and prominent U waves
• Hyperkalemia
  • Heart palpitations and chest pain
  • Hypotension
  • Dyspnea
  • Myalgia, cramps, and paresthesias 
  • Increased motility, hyperactive bowel sounds, and diarrhea
  • Ascending flaccid paralysis until the respiratory muscles become affected as a toxic level of serum potassium is reached
  • ECG changes: Tall peaked T waves, widened QRS complexes, and prolonged PR intervals

The Nursing Process

To ensure proper functioning and homeostasis the body must maintain a dynamic equilibrium of fluids and electrolytes. Organ system dysfunction, such as life-threatening dysrhythmias, can occur when potassium is not balanced. Nurses must closely monitor patients’ lab results and correct imbalances to prevent complications.

Nursing Care Plans Related to Hyperkalemia and Hypokalemia

Electrolyte Imbalance Care Plan

Electrolyte imbalance associated with potassium imbalance (hypokalemia/hyperkalemia) can be caused by conditions affecting the regulation, intake and excretion, and movement of potassium in the cellular space.

Nursing Diagnosis: Electrolyte Imbalance

Related to:

• Changes in the regulation of potassium
• Changes in the intake of potassium
• Difficulty excreting potassium
• Conditions that affect the movement of potassium in the cellular space

As evidenced by:

• Alterations in the electrical conductivity of the heart
• Ineffective respirations
• Muscle weakness and cramps
• Neuromuscular alterations
• Changes in bowel habits

Expected outcomes:

• Patient will demonstrate serum potassium levels within normal limits
• Patient will verbalize the absence of muscle pain or cramping
• Patient will not experience dysrhythmias

Electrolyte Imbalance Assessment

1. Monitor blood potassium levels.
Serum potassium levels should be monitored closely and redrawn as ordered to monitor for hypo/hyperkalemia.

2. Check renal function.
Excess potassium can build up in the body if damaged kidneys are unable to eliminate it. Assess urine output and kidney function through BUN, GFR, and creatinine levels.

3. Review the patient’s current medications.
Imbalanced potassium levels can be caused by drugs including diuretics, beta-blockers, and aminoglycosides. Hyperkalemia can result from taking potassium chloride or salt substitutes.

4. Review the patient’s diet.
Potassium levels can be influenced by the amount of potassium that is being consumed. Eating disorders such as bulimia nervosa and anorexia nervosa can lead to deficits in potassium.

Electrolyte Imbalance Interventions

1. Include or limit potassium in the diet.
Educate the patient on their prescribed diet depending on the condition. Potassium can be obtained as a dietary supplement but is naturally available in many foods. Bananas, spinach, broccoli, and some fish are high in potassium. If experiencing hyperkalemia, limit these foods in the diet.

2. Administer prescribed potassium with precautions.
Potassium can be administered IV or PO. If administering IV, infuse secondarily to a compatible IV solution such as 0.9% normal saline to minimize burning at the IV site.

3. Monitor strict intake and output.
Monitor urine output as well as bowel movements. Imbalanced levels can be caused by alterations in the intake and excretion of potassium.

4. Treat underlying conditions.
Potassium imbalances can be caused by kidney disease, diabetes, alcoholism, Addison’s disease, and more. Treating these conditions involves monitoring and preventing hypo/hyperkalemia.

Risk for Decreased Cardiac Output Care Plan

Risk for decreased cardiac output associated with potassium imbalance is caused by a disruption in the electric signals in the myocardium resulting in dysrhythmias.

Nursing Diagnosis: Risk for Decreased Cardiac Output

Related to:

• Changes in the conductivity in the heart
• Inability to pump blood effectively
• Disruption in the electric functioning of the heart

As evidenced by:

A risk for diagnosis is not evidenced by signs and symptoms as the problem has not yet occurred and nursing interventions are aimed at prevention.

Which rational supports the nurses assessment of a patients magnesium level?

Which clinical findings would the nurse evaluate in a patient with hypomagnesemia?

What patient should the nurse carefully assess for hypomagnesemia?

Which would be an appropriate instruction for a patient experiencing Hypermagnesemia?