A client is to receive 50 mL of intravenous solution in 45 minutes. The nurse should regulate the infusion pump to deliver approximately how many milliliters per hour?

• A. 37
• B. 45
• C. 52
• D. 67

Answer: (D)

Infusion rate is the amount of fluid delivered per unit time, so you divide the total volume by the time over which it’s given. Convert 45 minutes to hours: 45 minutes is 0.75 hours. Then 50 mL ÷ 0.75 h ≈ 66.7 mL per hour, which rounds to about 67 mL/h. That setting would deliver 50 mL in roughly 45 minutes. The other numbers would change the time: for example, at 37 mL/h it would take about 81 minutes to deliver 50 mL, at 45 mL/h about 67 minutes, and at 52 mL/h about 58 minutes.