CDN Renal Pharmacology for Dialysis Nurses 2 — Questions and Answers
Question 1: Heparin is administered at the start of hemodialysis primarily to prevent:
- Access infection
- Clotting in the extracorporeal circuit (Correct answer)
- Hypotension
- Membrane fouling
Correct answer: Clotting in the extracorporeal circuit
Heparin prevents thrombus formation in the blood tubing, dialyzer, and needle during passage of blood through the extracorporeal circuit.
Question 2: A dialysis patient is prescribed active vitamin D therapy. Which laboratory values must be monitored to prevent complications?
- BUN and creatinine
- Serum calcium and phosphorus (Correct answer)
- Serum potassium and sodium
- Hemoglobin and ferritin
Correct answer: Serum calcium and phosphorus
Active vitamin D (calcitriol or paricalcitol) can cause hypercalcemia and hyperphosphatemia, which must be monitored to prevent vascular calcification.
Question 3: Which medication requires dose adjustment or avoidance in dialysis patients due to accumulation of active metabolites that can cause neurological toxicity?
- Acetaminophen
- Meperidine (Demerol) (Correct answer)
- Ibuprofen
- Omeprazole
Correct answer: Meperidine (Demerol)
Meperidine's active metabolite normeperidine accumulates in renal failure and can cause seizures, making it contraindicated in dialysis patients.
Question 4: When should phosphate binders be administered to achieve maximum effectiveness?
- 30 minutes before meals
- With or immediately after meals (Correct answer)
- At bedtime
- During hemodialysis treatment
Correct answer: With or immediately after meals
Phosphate binders must be taken with meals to bind dietary phosphate in the gut before it is absorbed, reducing serum phosphorus levels.
Question 5: A dialysis patient on warfarin for atrial fibrillation requires more frequent INR monitoring. Why?
- Dialysis removes warfarin from the blood
- Altered protein binding and volume of distribution affect drug levels (Correct answer)
- Heparin used during dialysis reverses warfarin
- Vitamin K is removed by dialysis
Correct answer: Altered protein binding and volume of distribution affect drug levels
Uremia alters plasma protein binding and drug metabolism, making anticoagulation levels unpredictable and requiring more frequent INR monitoring.
Question 6: What is the rationale for timing the administration of intravenous antibiotics in hemodialysis patients?
- Antibiotics should be given 2 hours before dialysis
- Antibiotics should be dosed after dialysis to prevent removal by the procedure (Correct answer)
- Antibiotics are ineffective in dialysis patients
- Dialysis increases antibiotic bioavailability
Correct answer: Antibiotics should be dosed after dialysis to prevent removal by the procedure
Many antibiotics are dialyzable, so post-dialysis dosing prevents drug removal and ensures therapeutic blood levels persist until the next session.
CDN Renal Pharmacology for Dialysis Nurses 2
Heparin is administered at the start of hemodialysis primarily to prevent: