What is the infusion rate in mL/hour for a 400 mL infusion over 8 hours?

What is the infusion rate in mL/hour for a 400 mL infusion over 8 hours?

• A. 25 mL/hour
• B. 50 mL/hour
• C. 75 mL/hour
• D. 100 mL/hour

Answer: (B)

Infusion rate equals the total volume to be infused divided by the time over which it should be delivered. Here, 400 mL over 8 hours means 400 ÷ 8 = 50 mL per hour. So infuse at 50 mL/hour. If you infused at 50 mL/hour for 8 hours, you’d deliver exactly 400 mL; other rates would deliver different totals (e.g., 25 mL/hour would give 200 mL in 8 hours, 75 mL/hour would give 600 mL, etc.).

Infusion rate equals the total volume to be infused divided by the time over which it should be delivered. Here, 400 mL over 8 hours means 400 ÷ 8 = 50 mL per hour. So infuse at 50 mL/hour. If you infused at 50 mL/hour for 8 hours, you’d deliver exactly 400 mL; other rates would deliver different totals (e.g., 25 mL/hour would give 200 mL in 8 hours, 75 mL/hour would give 600 mL, etc.).