A total of 2000 mL is to be infused over 40 hours. What is the infusion rate in mL per hour?

A total of 2000 mL is to be infused over 40 hours. What is the infusion rate in mL per hour?

• A. 40 mL/hr
• B. 60 mL/hr
• C. 80 mL/hr
• D. 50 mL/hr

Answer: (D)

Infusion rate is found by dividing the total volume by the time over which it’s administered. Here, 2000 mL over 40 hours: 2000 ÷ 40 = 50 mL per hour. So set the rate to 50 mL/hr. If you used 40 mL/hr, you’d deliver 1600 mL in 40 hours; at 60 mL/hr you’d deliver 2400 mL; at 80 mL/hr you’d deliver 3200 mL—none of these match the 2000 mL total. The correct rate is 50 mL per hour.

Infusion rate is found by dividing the total volume by the time over which it’s administered. Here, 2000 mL over 40 hours: 2000 ÷ 40 = 50 mL per hour. So set the rate to 50 mL/hr. If you used 40 mL/hr, you’d deliver 1600 mL in 40 hours; at 60 mL/hr you’d deliver 2400 mL; at 80 mL/hr you’d deliver 3200 mL—none of these match the 2000 mL total. The correct rate is 50 mL per hour.