Hypokalemia Lecture Notes

Introduction

• Presenter: Sarah, Register Nurse RN
• Focus: Simplifying hypokalemia for exams (lecture exams, NCLEX)
• Additional Resource: Visit register nurse rn.com and take the free quiz on hypo and hyperkalemia.

Understanding Hypokalemia

• Break down the word:
  • Hypo: Low
  • Kal: Potassium
  • Emia: Blood
• Normal Potassium Levels: 3.5 to 5.1 mEq/L
  • Less than 2.5 mEq/L is dangerous and requires intervention.

Cellular Level Dynamics

• Intracellular vs. Extracellular: Potassium is mainly intracellular.
• Blood tests measure extracellular potassium.
• Low potassium in blood affects nerve impulses and muscle contractions.
  • Issues: GI system, heart, respiratory muscles.

Causes of Hypokalemia

• Mnemonic: DITCH
  • D: Drugs (laxatives, diuretics, corticosteroids)
  • I: Inadequate intake of potassium (due to anorexia, sickness, etc.)
  • T: Too much water intake (dilutes potassium)
  • C: Cushing's syndrome (excess aldosterone)
  • H: Heavy fluid loss (NG suction, vomiting, diarrhea, wound drainage, sweating)
• Other causes:
  • Alkalosis
  • Hyperinsulinism

Signs and Symptoms

• Potassium is crucial for muscle and nerve conduction.
• Symptoms: Everything is slow and low due to low energy levels.
  • Weak, irregular pulse
  • Orthostatic hypotension
  • Decrease in bowel sounds
  • Decreased deep tendon reflexes
  • Flaccid paralysis
  • Confusion
  • Shallow respirations
  • Diminished breath sounds
  • EKG Changes: Depressed ST segment, flat/inverted T-wave, prominent U-wave

Mnemonic: 7 L's for Symptoms

1. Lethargic
2. Low shallow respirations
3. Lethal cardiac changes
4. Loss of urine
5. Leg cramps
6. Limp muscles
7. Low blood pressure and heart rate

Nursing Interventions

• Monitor heart rhythm, respiratory status, GI and renal function.
• Cardiac monitoring: necessary for potassium infusions > 10 mEq/hr.
• Monitor magnesium, glucose, calcium, and sodium levels.
• Potassium Supplements:
  • Oral for levels 2.5-3.5 mEq/L
  • IV infusion for levels < 2.5 mEq/L (never IV push or IM injection)
• Adjust medications that affect potassium levels (diuretics, digoxin)
  • Consider potassium-sparing diuretics (e.g., Spironolactone)
• Encourage potassium-rich foods:
  • Mnemonic: POTASSIUM
    • P: Potatoes, Pork
    • O: Oranges
    • T: Tomatoes
    • A: Avocados
    • S: Strawberries, Spinach
    • I: Fish
    • U: Mushrooms
    • M: Musk melons, Carrots, Raisins, Bananas

Conclusion

• Review hypocalcemia and take the quiz to test knowledge.
• Check out additional tutorials and subscribe for more content.

These notes are intended to help understand hypokalemia and are supplemented with resources from the Register Nurse RN website.