NCLEX-PN® ExaminationPharmacological TherapiesMedium
A client is receiving an intravenous infusion of heparin sodium at 1,200 units/hour. The pharmacy supplies heparin in a concentration of 25,000 units in 500 mL of 0.9% sodium chloride. The LPN needs to calculate the infusion pump rate in mL/hour. What is the correct infusion rate?
- A12 mL/hour
- B30 mL/hour
- C24 mL/hour
- D20 mL/hour
Show answer & explanationAnswer & explanation
Correct answer: C. 24 mL/hour
To calculate the infusion rate, use the formula: (Desired Dose / Available Concentration) × Volume. (1200 units/hour / 25000 units) × 500 mL = 24 mL/hour.
Why the other options are wrong
- A. Incorrect calculation. This would be 600 units/hour.
- B. Incorrect calculation. This would be 1500 units/hour.
- D. Incorrect calculation. This would be 1000 units/hour.
IV Infusion Rate Calculation
Calculating the infusion pump rate (mL/hour) for continuous intravenous medications based on desired dose and available concentration.
- Formula: (Dose ordered / Dose on hand) × Volume on hand.
- Ensure units are consistent (e.g., units/hour, mg/hour).
- Result is typically in mL/hour for pump settings.
Memory trick: DRIP: Dose Rate In Pump