Quote from KerriN
Hi, I've never posted before, but I need help now. I am trying to test out of the dosage calculation course. I have a few answers that are different than the ones on the study guide and can't seem to contact anyone that can go over them w/me. Those of you who enjoy math and want to help, I would really appreciate it!
The first one is a two part question:
Order:Ampicillin 1g added to 50mL of NS q12hr. Infuse over 45 min
Supply: Ampicillin 5g/10mL
IV Tubing: 60gtt/mL
What volume will the nurse draw up to deliver ordered medication?
Answer: 2mL (I agree w/this)
What is the gtt/min? Answer: 66gtt/min
(Shouldn't the answer be 69gtt/min since the new volume is 52mL? My calculations are : 52mL/45min X 60gtts/1mL = 69gtts/min)
Please straighten me out if I'm wrong!!
Thanks ahead of time for anyone's input
The difference between 66 and 69 gtt/min is completely negligable. When you are calculating drops per minute, do not add the mL's of Ampicillin you are adding to the NS, unless it is a very large amount (which probably would not happen).
The reason for this is that gtt/min are not a perfect science. You only use them if the IV is not on a pump (unlikely, unless you work ER). You monitor the gtt/min by eye, and the rate can change even if the patient so much as raises their arm. That is why the study guides never add in the extra amount that you will add, because it makes no difference in the long run.
Double check with your teacher just to be sure... but in general, if they ask you to calculate gtt/min on problems like this, calculate it from the original amount of fluid they gave you in the problem.
Don't throw your study guide out, that's what helped me pass the test!
I can't help you with the second question. I got the same answer you did. And even if they went by the mfr, the answer would be 10.5, not 10. Again, ask your teacher for help.