Hyperkalemia and Hypokalemia

Hyperkalemia and Hypokalemia

Normal Potassium Level

  • Normal potassium level (K+): 3.5-5.0 mEq/L

Role of Potassium (K+)

  • Potassium plays an important role in:

    • Muscle function

    • Nerve conduction

Hyperkalemia

  • Definition:

    • Excessive potassium in the blood.

    • Characterized by potassium levels > 5.0 mEq/L.

  • Cellular Distribution:

    • More than 95-98% of potassium is found in the intracellular space.

    • Hyperkalemia occurs when potassium moves out of the intracellular space into the extracellular space (blood).

  • Causes:

    • Usually occurs in patients with impaired kidney function where K+ is not excreted properly.

    • Associated conditions:

    • Addison's Disease

    • Excessive potassium intake

    • Medication therapy such as:

      • Spironolactone

      • ACE inhibitors

      • Uremia (USADS)

Signs & Symptoms of Hyperkalemia

  • Anuria (absence of urine output)

  • Oliguria (decreased urine output)

  • Muscle twitching

Hypokalemia

  • Definition:

    • Low potassium in the blood.

    • Characterized by potassium levels < 3.5 mEq/L.

  • Cellular Distribution:

    • Potassium in the extracellular space shifts into the intracellular space leaving low levels in the blood.

  • Causes:

    • Cushing Syndrome

    • Excessive use of potassium-wasting diuretics & corticosteroids

    • Suctioning, vomiting

Signs & Symptoms of Hypokalemia

  • Altered mental status: confusion, lethargy

  • Decreased peristalsis

  • Fatigue and muscle weakness

  • Orthostatic hypotension

  • Severe hypokalemia may cause:

    • Paralytic ileus

    • Abnormal ECG Rhythm:

    • ST depression

    • Prominent U wave

    • Shallow T wave

Normokalemia

  • Potassium levels are within the normal range

Nursing Interventions

For Hyperkalemia

  • Conduct cardiac, neuromuscular, and respiratory monitoring

  • Dialysis for patients with renal insufficiency

  • Stop potassium supplements (IV infusions or PO supplements)

  • Educate patients and family members to avoid foods high in potassium

Medication Therapy for Hyperkalemia

  • Kayexalate:

    • Given through the rectum, Kayexalate binds in the digestive tract to help prevent the body from absorbing excess potassium.

    • Increases the excretion of potassium via feces.

  • Potassium-wasting diuretics, examples:

    • Lasix (Furosemide)

    • Hydrochlorothiazide

  • Glucose & Insulin: Helps drive potassium back into the cells.

ECG Changes in Hyperkalemia

  • Slightly prolonged PR interval

  • ST depression

  • Peaked T wave

  • Shallow T wave

Nursing Interventions for Hypokalemia

  • Conduct cardiac, neuromuscular, and respiratory monitoring

  • Provide potassium-rich foods such as:

    • Bananas

    • Potatoes

    • Poultry

    • Nuts

    • Fish

    • Cheese

  • Administer Potassium PO

  • Administer IV potassium for severe hypokalemia:

    • Watch IV site for phlebitis or infiltration

    • Do not exceed 20 mEq/hr

    • Always use a pump to administer

    • Never administer potassium IV push as it may cause cardiac arrest.