Published Jan 30, 2015
Heaven-Leigh
22 Posts
I've been trying to self teach myself about IV drip rates, but I'm stumped on one particular problem:
"The nurse sets up a 1000cc bag of normal saline. The IV tubing has a drop factor of 15 drops/ml/minute. How many drops/minute will the saline be administered?"
So far when I googled IV flow rate formulas, I've seen:
Volume(ml) X drop factor divided by time.
I'm not looking for someone to just answer the question, I'd like know how to calculate it. I tried figuring it out by plugging the 1000cc volume X 15 gtts, divided by... 1? For 1 minute? But that's not right. Is there another formula for calculating the drops per minute?
The answer is 25 drops per minute, but I don't know how.
meanmaryjean, DNP, RN
7,899 Posts
There's an obvious typo in the problem because there is a crucial factor missing: the RATE of the infusion.
Doesn't it make you nuts when you try and try to figure something out and it ends up not being YOU but the problem itself? :)
RunBabyRN
3,677 Posts
I was going to say, it doesn't say a thing about how long you need to infuse the bag over. You need to know that in order to calculate the rate (or you need to know the rate so you can figure out the drops).
Esme12, ASN, BSN, RN
20,908 Posts
DosageHelp.com - Helping Nursing Students Learn Dosage Calculations
Thread moved for best response.
You are missing a part of the calulation information to do the calculation....Calculate the IV flow rate for 1200 mL of NS to be infused in 6 hours. The infusion set is calibrated for a drop factor of 15 gtts/mL. [TABLE=class: example]
[TR]
[TD] [TABLE=class: fraction]
[TD=class: numerator] Volume (mL)
[/TD]
[/TR]
[TD=class: denominator] Time (min) [/TD]
[/TABLE]
[TD] x Drop Factor (gtts/mL) = Y (Flow Rate in gtts/min)
Convert 6 hours to minutes.
[TABLE=class: example]
[TD=class: numerator] 1200 mL
[TD=class: denominator] 360 min [/TD]
[TD] x 15 gtts/mL = 50 gtts/min[/TD]
nurseprnRN, BSN, RN
1 Article; 5,116 Posts
You (and any of us) can't answer this question as given, because you don't know how fast to give the liter. If, for example, you had to give the whole liter in an hour, the thing would be running at a lot faster drip rate than if you were giving 100cc/hour, right? So ... you stop right there and say, "I can't answer this because a critical fact is missing."