A client experiencing cardiogenic shock receives a prescription for an IV infusion of milrinone (Primacor) 10 mg in 100 ml at a rate of 46 mcg/min. The nurse should program the infusion pump to deliver how many ml/hour?

• A. 20
• B. 28
• C. 34
• D. 46

Answer: (B)

The idea is to convert the requested drug rate from micrograms per minute into milliliters per hour using the solution’s concentration.

First, find the concentration: 10 mg in 100 ml equals 0.1 mg/mL, which is 100 mcg/mL. The desired dose is 46 mcg per minute, so the volume to infuse each minute is 46 mcg/min ÷ 100 mcg/mL = 0.46 mL/min.

Convert to hours: 0.46 mL/min × 60 min/hour = 27.6 mL/hour, which is typically rounded to 28 mL/hour for pump settings.