Nursing Calculations When you're on Your Own

[FrequentlyLost]

Hi, everyone. I'm an LPN student on her first semester. Each semester we'll have a math competency test, and I have no experience with dosing calculations. We've kinda been thrown into it with just two packets with problems to solve, without having it explained how to do them, and I'm someone that has a lot of issues with math (I'm literally having to re-learn long division). Could someone help me out with the proper formulas for finding drug/solutes in solution, preparing feeding tubes, expressing solution strength, and # of tabs, caps, or mL to prepare? I'm kinda running blind here and every website or video I've found so far has different names for all of it, and I can't recognize which one is which.

[RN403, BSN, RN]

Can you please post an example of a question that you are having trouble with, it'd be easier to help you work through the problem.

You also might try dosagehelp.com - it is very helpful.

[FrequentlyLost]

I tried DosageHelp. It's too vague for me.

A preparing tube feedings question: 25% Nutrivent must be prepared for a tube feeding. You have available full strength Nutrivent. To prepare 400 mL of feeding, you dilute __ mL of the full strength Nutrivent with ___ mL of water.

It's questions like these. There's no formula for how to figure out something like that that I've found yet, or one like this

"How many g of lidocaine HCl does a patient receive when 45.5 mL of a 0.5% solution is administered?"

[RN403, BSN, RN]

Yes, I see that DosageHelp does not seem to give much guidance on tube feeding calculations.

I found this site that might be of assistance towards helping you with these types of calculations:

Tube Feedings

After viewing this link, please post if you need further assistance with this type of calculation.

[pjmiller]

Having a problem trying to solve dosage calculation.

I know I am wording it wrong, just want to know how to do the math.

Start with 400 ml D5W with KCL 8 mEq/100ml infuse over 8 hours. You have KCL of 20mEq 10 ml. How many ml of KCL do you add.

THe answer is 16, but I don't know how the math was done.

Thank you.

[cinlou, BSN, MSN, RN]

The best formulas for calcs and conversions are dimensional analysis, everything is done in one formula. You can learn using ratio and proportion but you have to do a few more steps. Does your fundamentals book have a workbook, much of what you need should be in their. Go to you tube and search dimensional analysis, there are many examples that show you how to do it.