IV therapy calculation question

IVRUS, BSN, RN · Mar 1, 2012

Amanda,a search of the threads on this wonderful website will bring you numerous "hits" to answer this question, however, I'll copy and paste a previous reply which should help you:

Your best bet is to follow this formula:

First thing is to find flow rate. The flow rate is what you are setting your pump to. Pumps work in mls per hour.

So, in this case, you have an order to infuse 25 mls an hour.

Now, since you do NOT have a pump, and you want to calculate gtts/per minute so that the medication will go in in the appropriate time frame follow this formula:

If your tubing is 10gtts/ml, divide your flow rate by 6. So, 200/6 = 33.3 gtts/minute

If your tubing is 15gtts/ml, divide your flow rate by 4. So, 200/4 = 50 gtts/minute

If your tubing is 20gtts/ml, divide your flow rate by 3. So, 200/3 = 66.6gtts/minute

This doesn't require a lot of memory power either, if one just thinks of a standard clock. When looking at a clock, how many 10 second intervals are there in a minute? 6

how many 15 second intervals are there in a minute? 4

how many 20 second intervals are there in a minute? 3

And, if you have mini, or micro gtt tubing (60gtts/ml) whatever your flow rate is, will be your gtts per minute.

So, if your tubing is mini or micro gtt tubing, your flow rate will be the same as you flow rate = 25gtts/min.

Please note, however, that it is never a good idea to have anything over 500 cc in volume hang to gravity. Use an on line regulator, if possible when a pump isn't available.

lyndsyalyce · Mar 1, 2012

V x DF •/• 60=gtt/min when hours are provided

So: 25 ml/hr x 60 gtt/ml •/• 60= 25gtt/min

V x DF •/• time in min=gtt/min when minutes are provided

As long as you know the formulas and work some practice problems from your book, you will always get the correct answer.