What is the correct setting for a burette pump to administer 60 mL of fluid containing 75 mg of ranitidine in 35 minutes?

What is the correct setting for a burette pump to administer 60 mL of fluid containing 75 mg of ranitidine in 35 minutes?

• A. 103 mL/h
• B. 102 mL/h
• C. 105 mL/h
• D. 100 mL/h

Answer: (A)

The key idea is to set the pump by volume per time. You need to deliver 60 mL over 35 minutes. Convert 35 minutes to hours: 35/60 = 0.5833 h. The required rate is 60 mL divided by 0.5833 h, which is about 102.86 mL/h. Since pumps are set to whole milliliters per hour, the closest practical setting is 103 mL/h. That setting will deliver 60 mL in roughly 60/103 h ≈ 0.5825 h, which is about 34.95 minutes, essentially 35 minutes. The dose is 75 mg in 60 mL, which is 1.25 mg/mL; delivering 60 mL at this rate means about 75 mg will be given in the 35-minute window, consistent with the requirement. Other nearby rates would shift the timing a bit more; for example, 102 mL/h would take about 35.29 minutes, while 100 or 105 mL/h would deviate more from 35 minutes.

The key idea is to set the pump by volume per time. You need to deliver 60 mL over 35 minutes. Convert 35 minutes to hours: 35/60 = 0.5833 h. The required rate is 60 mL divided by 0.5833 h, which is about 102.86 mL/h. Since pumps are set to whole milliliters per hour, the closest practical setting is 103 mL/h.

That setting will deliver 60 mL in roughly 60/103 h ≈ 0.5825 h, which is about 34.95 minutes, essentially 35 minutes. The dose is 75 mg in 60 mL, which is 1.25 mg/mL; delivering 60 mL at this rate means about 75 mg will be given in the 35-minute window, consistent with the requirement.

Other nearby rates would shift the timing a bit more; for example, 102 mL/h would take about 35.29 minutes, while 100 or 105 mL/h would deviate more from 35 minutes.