What is the required flow rate to deliver 500 mL of Hartmann's solution over 7 hours?

What is the required flow rate to deliver 500 mL of Hartmann's solution over 7 hours?

• A. 68 mL/h
• B. 75 mL/h
• C. 72 mL/h
• D. 71 mL/h

Answer: (D)

To deliver a set volume over a fixed time, use flow rate = volume ÷ time. Here, 500 mL over 7 hours gives 500 ÷ 7 = 71.428... mL per hour. In IV calculations we typically round to the nearest whole mL per hour, so about 71 mL/h. That rate will closely achieve 500 mL in 7 hours. The other options would deliver noticeably more or less than 500 mL in the same time frame (68 mL/h would yield about 476 mL, 72 mL/h about 504 mL, and 75 mL/h about 525 mL), so 71 mL/h is the best match.

To deliver a set volume over a fixed time, use flow rate = volume ÷ time. Here, 500 mL over 7 hours gives 500 ÷ 7 = 71.428... mL per hour. In IV calculations we typically round to the nearest whole mL per hour, so about 71 mL/h. That rate will closely achieve 500 mL in 7 hours. The other options would deliver noticeably more or less than 500 mL in the same time frame (68 mL/h would yield about 476 mL, 72 mL/h about 504 mL, and 75 mL/h about 525 mL), so 71 mL/h is the best match.