Lecture Notes: Diuretics

Overview

• Diuretics are medications that increase urine production, helping rid the body of excess fluid.
• Memory trick: Diuretics = "Dry Inside."

Types of Diuretics

1. Loop Diuretics

   • Common drugs: Furosemide (Lasix), Bumetanide, Torsemide
   • Mechanism: Inhibits reabsorption of sodium and chloride in the kidneys (distal tubules, proximal tubules, loop of Henle)
   • Effects: Potassium wasting, risk of hypokalemia
   • Nursing Considerations:
     • Monitor potassium levels; replace if needed orally or intravenously (IV)
     • Oral potassium should not be crushed or chewed
     • Avoid IV push of potassium; use infusion pump
     • Administer furosemide slowly to prevent ototoxicity

2. Thiazide Diuretics

   • Common drugs: Hydrochlorothiazide, Chlorothiazide
   • Mechanism: Inhibit reabsorption of sodium and chloride, less potent than loop diuretics (acts on ascending loop of Henle and early distal tubule)
   • Effects: Potassium wasting, risk of hypokalemia
   • Nursing Considerations:
     • Monitor potassium levels
     • Avoid in patients with gout or sulfa allergy

3. Potassium-Sparing Diuretics

   • Common drug: Spironolactone (Aldactone)
   • Mechanism: Blocks aldosterone, spares potassium
   • Effects: Risk of hyperkalemia
   • Nursing Considerations:
     • Monitor for hyperkalemia
     • Educate patients to avoid potassium-rich foods and supplements

4. Osmotic Diuretics

   • Common drug: Mannitol (Osmotrol)
   • Mechanism: Increases filtrate thickness in kidneys, preventing water reabsorption; used for cerebral edema and intraocular pressure
   • Nursing Considerations:
     • Administer IV only
     • Check for crystallization
     • Perform neuro assessments if used for cerebral edema

General Nursing Considerations for Diuretics

• Educate patients to take diuretics in the morning to avoid nocturia
• Monitor for orthostatic hypotension
• Encourage low sodium diet to prevent water retention
• Monitor daily weights for significant changes
• Measure intake and output (I&O) and potassium levels

Potassium Wasting vs. Potassium Sparing

• Potassium Wasting: Loop and Thiazide diuretics
• Potassium Sparing: Spironolactone (Sparing = S)

Practice Question

• Scenario: Nurse with congestive heart failure patient on spironolactone.
• Concern: Potassium level of 5.3 (above normal range of 3.5-5.0) should be reported before medication administration.

Additional Resources

• NCLEX study notebook for practice questions and study scheduling.

Conclusion

• Diuretics are vital in managing fluid retention associated with conditions like heart failure and kidney disease.
• Understanding the type and mechanism of diuretics helps in effective patient management and reducing potential side effects.
• Further study on antihypertensives is recommended for comprehensive understanding.