A 350 mL bag is to be infused over 70 minutes. What is the flow rate in mL/h?

A 350 mL bag is to be infused over 70 minutes. What is the flow rate in mL/h?

• A. 300 mL/h
• B. 250 mL/h
• C. 350 mL/h
• D. 400 mL/h

Answer: (A)

Flow rate is the amount of fluid delivered per hour. To get mL per hour, divide the total volume by the infusion time, making sure the time is in hours. Here, 70 minutes equals 70/60 hours, so the rate is 350 mL ÷ (70/60 h) = 350 × 60 ÷ 70 = 300 mL/h. If you infused at other rates, you’d finish in shorter or longer times: for example, 350 mL/h would finish in 60 minutes, and 250 mL/h would take about 84 minutes.

Flow rate is the amount of fluid delivered per hour. To get mL per hour, divide the total volume by the infusion time, making sure the time is in hours. Here, 70 minutes equals 70/60 hours, so the rate is 350 mL ÷ (70/60 h) = 350 × 60 ÷ 70 = 300 mL/h. If you infused at other rates, you’d finish in shorter or longer times: for example, 350 mL/h would finish in 60 minutes, and 250 mL/h would take about 84 minutes.