IV Calculations

it seems maybe its a 2 step problem

First find out how long it would take 1000 mL to infuse at 50mL/hr... i got 20 hours

Next 60gtt/1mL x 1000mL/1200min(20 hours in minutes) = 50 gtt/min

Now i think that is what it is, i gotta go back and review Iv calculations myself

Am I dividing the volume the 1,000 into the 50/ml to get the first answer?

Thanks, I have become very good at ignoring the other numbers, they try to trick you on these types of questions, I am finding that in my Foundations of Nursing course also. Having kids, I think ignoring things comes like breathing to me! thanks for your help I will try to work these out!

The way this second problem is presented, isn't too clear. Exactly WHAT do you need to know for this problem? Do you need to need how many hours it is to run for the entire infusion and then gtt/ minute or just gtt/ minute?

In order to figure gtt/ minute on the 2nd problem, all you need is the gtt/ml and ml/hr. The other information (1000 ml of D5 .045% NS) is superfluous, meant to throw you off. You have to learn to sort out the unnecessary information from the absolutely critical information. Afterall, this is the way it is in "real life." Always ask yourself - WHAT is the problem asking? WHAT parameters do I need to work out this problem? Then throw out the rest.

To figure gtt/ minute, start with dose desired (gtt):

60 gtt X 50 ml X 1 hr = 50 gtt

ml 1 hr 60 min min

(Or 60 gtt/ml X 50 ml/1 hr X 1 hr/60 minutes = 50 gtt/ minute)

However, if you also need to know HOW MANY HOURS of infusion (1000 ml D5 0.45% NS @ 50 ml/ hr), again you need to know what information you need and which is unnecessary. You don't need to know the D5 0.45% NS. All you need to know is 1000 ml and 50 ml/hr.

To figure hours of infusion, start with dose desired (hr):

1 hr X 1000 ml = 20 hours of infusion

50 ml infusion

(Or, 1 hr/50 ml X 1000 ml/ infusion = 20 hours of infusion)

Hope this helps :)

Thanks for all your responses, I guess I better start practicing, as you can see math is not one of my strong points and I really need to get it straight. Thanks!

This one is difficult for me due to the fact I can not figure the equation:

1 Liter (1,000ml) of D5 o.45% NS at 50ml/hr, Drop Factor 60gtt/ml. UGH!

Ok here is how I set up all my IV calculations - O/T X D /60

Where O=order, T=time in hours, D=drop factor, and the 60 is for gtt/ml(breaking it down to seconds)

The section O/T gives you ml/hr....

Knowing this, it makes it apparent that the 1,000ml is not needed when you notice 50ml/hr.

So you are left with 50(hourly rate) x 60 (drop factor) /60(breaking it down to seconds)

Which gives you 50 gtts

Hopefully this is easier to understand for anyone stumbling across this thread than the other posts here trying to explain, because that was my intent! Hope it helps!