I have a math question that pertains to infusion rate and gtt/min

Here is the question I must be getting tired my brain needs help on this one even if you just point me in the right direction, i can do the math thanks so much

infuse 500 ml of lactated ringers over 4 hours the IV tubing has a drop factor of 15 gtt/ml. What is the infusion rate in gtt/min?

2ndyearstudent, CNA · Nov 18, 2010

Here is the question I must be getting tired my brain needs help on this one even if you just point me in the right direction, i can do the math thanks so much
infuse 500 ml of lactated ringers over 4 hours the IV tubing has a drop factor of 15 gtt/ml. What is the infusion rate in gtt/min?

If you use dimensional analysis, you don't have to worry about remembering or manipulating a formula:

500ml/4h x 1h/60min x 15gtt/ml = 31.25 or 30 gtt/min

There are shortcuts using a drop factor but I don't like using them. The shortcut method is:

1. Figure the flow rate in ml/hour.

2. This is equal to the gtt/min for if the drop factor is 60gtt/min.

3. If the drop factor is something else, divide 60 by the drop factor.

4. Divide the answer you got in 2 by the answer you got in 3.

So your flow rate in your problem is 125ml/hr. 60 divided by 15 is 4. So divide 125 by 4 to get 31.25 gtt/min.

I like the DA way.