calculation problem

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Can someone please help me with this calculation? I'm not just looking for an answer, but how do you go about getting the answer. Thanks so much

Order: add 2 grams Thiamine to 1000 cc IV fluids

Available: 500 per 5cc

Volume in IV fluid bag 500 cc.

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Specializes in Med/Surg.
Can someone please help me with this calculation? I'm not just looking for an answer, but how do you go about getting the answer. Thanks so much

Order: add 2 grams Thiamine to 1000 cc IV fluids

Available: 500 per 5cc

Volume in IV fluid bag 500 cc.

Assuming your available is 500mg of Thiamine per 5 cc. The ratio is easy as it is 100mg/1 cc Thiamine, therefore, you will need to add 10 cc or 1000mg of Thiamine to each bag of 500 cc. So you will end up with 2 bags each of 510 CC with 10 cc (1000 mg) of Thiamine. Does that make sense?

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I guess it should make sense, but it's not clicking right now.

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Specializes in Med/Surg.
I guess it should make sense, but it's not clicking right now.

Okay, I'll try to explain it more clearly.

You have (500 mg/ 5 cc). You need 2000 mg. 2000 mg/ 500mg = 4 ( 5 cc) you will need 20 cc of Thiamine to equal the 2gm dose. Since you only have 500cc bags of IV fluids and the order called for 1000cc of IV fluid, you will put half the Thiamine, 10 cc, in each bag. Any better?

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yeah, that's a little better..it's just that I have such a hard time setting up the equation. The math part is easy, just setting up the equation in the right way is what I'm finding hard to do.

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Specializes in Med/Surg.

I would set it up like this (2 gm Thiamine) * ( 1000 mg/1 gm) * (5 cc Thiamine / 500 mg Thiamine) = 20 cc Thiamine

I don't really think the second part needs an equation.

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Thank you so much. Hope you have a blessed day:)

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Wondering if you could walk me through this last one.

Order:500 cc D5W with 20 mEq KCL

Avail: 15 mEq/7.5cc

How many cc of the KCl must be added to the IV bag?

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Specializes in Med/Surg.
Wondering if you could walk me through this last one.

Order:500 cc D5W with 20 mEq KCL

Avail: 15 mEq/7.5cc

How many cc of the KCl must be added to the IV bag?

OFC...

(20 mEq KCl) * (7.5cc KCl / 15 mEq KCl) = 10 cc KCl

You will need to add 10 cc KCl to a 500cc D5W bag to complete the order. Just make sure to always start the equation with what you are looking for and then arrange the given concentration (this will cancel the measurements) so that you have the desired measurement on top (for additions you will always be looking for cc/mLs). Hope this helps!!

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Thank you!! I promise not to bother you again! I guess it will just take more time and practice to get this down pat!!

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So in that problem, the 500 cc D5W does not matter at all correct?

I mean as far as the calculation part

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Specializes in Med/Surg.

Nope its just the type of fluid it wants you to mix it in, it could be 500 cc 0.9%NaCl or D50.45%NaCl.

You can bother me about this any time I am happy to help :)

I took 3 years of calculus and 3 years of advanced chemistry in school this is as close as I get to the good old days :smokin:

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