IV Drip Rate

by Sara
(Texas)

Can you explain how to do the following problem from Bonus Quiz 8?

An IV Drip containing 400 mg of a drug in a 500 mL solution is ordered to run at 20 gtt/min. How much of the drug will the patient receive in 3 hours if the infusion set is calibrated to deliver 15 gtt/mL?

A. 240 mg

B. 192 mg

C. 212 mg

D. 182 mg

Thank you.

Reply (by Keith)

Many people will first try to start working out percentages to figure this out. That is time consuming and unnecessary. So, just basic and proportion math is needed. Here's one way to do this:


First determine how many mL will be delivered:

180 Minutes X 20 drops = 3600 drops delivered



3600 drops / 15 gtt/mL = 240 mL delivered



Then do proportion Math:



400mg/500mL = X/240ml



X = 192 mg