My professor had this math question on one of our nursing exams and the whole class was stumped.
I don't remember the question word for word but I'll do my best.
You need to give 12units of a 70/30 mixed solution how many units do you draw of each. Regular Insulin __________ NPH ________
My answer was: Regular: 8.4 units and NPH: 3.6 and I got the question wrong. I think I might have just put the answers in the wrong order because you don't want to give more of the fast acting insulin, right? Or am I totally wrong, I'f so can someone please explain, which goes first and why and how to do the math if my math was indeed wrong.
We have another exam Monday and we need to make sure we are doing this right.
Ok, I think I have the right answer for you now, I was just re-reading the post and thought of something else. Already prepared mixtures of 70/30 are 70% NPH and 30% regular.
So my final answer is this: Units can't be divided... so you must round. If the question is asking for 70/30 it would be 70% NPH, so for 12 total units you'd draw up 8 units of NPH, and 30% regular would be 4 units. pull up 12 units of air, put 8 units of air into the NPH. Withdraw your syringe and needle, put the remaining 4 units of air into the regular, then draw up your 4 units of regular. Next draw up your 8 units of NPH.
So its 8 units NPH, 4 units regular.
I think the question was just poorly worded. It seems (to me) to be asking how much of each insulin is in 12 units of the premixed 70/30.
That's a bizarre question! If you needed a 70/30 ratio insulin, you use a commercially prepared solution. If you have to give NPH and Regular the order has to be specifically ordered for each number of units for each type insulin. No doctor is going to write an order like that, and if they did I wouldn't be giving it until clarified.
Gotta love nursing school....testing on the real world...not so much!! LOL!
I agree...
Sounds to me like its one of those tricky nursing school questions which makes you think WAY harder than you need to...
I would have answered 12units of the 70/30 NPH, 0 units regular
Specializes in icu, er, transplant, case management, ps.
I have to give myself 35 units of NPH and 10 units of regular insulin. So when I draw it up, I draw up 35 units of NPH first and 10 units of regular insulin second.
Let me guess, you are a student at LIU Brooklyn Center. Things haven't change since I got my BSN in 1973. Still the same stupid questions on exams.
Specializes in critical care; community health; psych.
We still use 70/30. I am a fool, but I would think that if the doctor asked for 12 units of 70/30, that is just what I would have pulled up. Altering it in another way would change the concentration of the insulin he is asking that you draw. That is just me...but beachbum's answer sounded good, too. Did your professor answer you guys, yet? When he/she does, please post it.
Yeah, this sounds like a trick question. 12 units of a mixed solution of anything is 12 units.
I have to give myself 35 units of NPH and 10 units of regular insulin. So when I draw it up, I draw up 35 units of NPH first and 10 units of regular insulin second.
Let me guess, you are a student at LIU Brooklyn Center. Things haven't change since I got my BSN in 1973. Still the same stupid questions on exams.
Woody
When you are drawing from vials that are for community use, though, you have to draw regular first... as regular is the only kind that can be used IV. If you draw NPH first you run the risk of mixing NPH into the Regular. Obviously for those at home or self administration it doesn't matter what order because you wouldn't be using your own vials for IV use.
We actually had a question like this on a test before and they wanted to know if you had to mix it yourself how much would you draw up of each.
I just typed out that maybe they want us to know it in case someone is ordered 70/30 and there isn't any available and we need to mix it ourselves... but now I'm wondering, if its ordered for the 70/30 can you mix it yourself, or is that considered a different med, so you'd need a different order for it?
We actually had a question like this on a test before and they wanted to know if you had to mix it yourself how much would you draw up of each.
I just typed out that maybe they want us to know it in case someone is ordered 70/30 and there isn't any available and we need to mix it ourselves... but now I'm wondering, if its ordered for the 70/30 can you mix it yourself, or is that considered a different med, so you'd need a different order for it?
if it was ordered to be mixed, it would have to be ordered as ____unit nph and _____ units reg.
put it this way, that is the only way i would administer it.
Specializes in icu, er, transplant, case management, ps.
When you are drawing from vials that are for community use, though, you have to draw regular first... as regular is the only kind that can be used IV. If you draw NPH first you run the risk of mixing NPH into the Regular. Obviously for those at home or self administration it doesn't matter what order because you wouldn't be using your own vials for IV use.
When I have been a patient, in NYS and Florida, my NPH and regular insulin came in individual vials, not a community sized vial. And it does make a difference in which order you draw your insulin. Make an error in pulling, and you contaminate the other vial with a different insulin. To be honest, when I have to combine NPH and regular insulin, I draw up my NPH initially, draw up six units of air then draw up my regular insulin, to avoid contaminating either, which I have done.
This is a poorly worded test question. Having completed more then half of the required credits for a Masters in Nursing Education, I would use this question as an example of how not to word a question. And any student who sees such a poorly worded question, should draw it to the attention of the Chairman of the Nursing Department. And if one is afraid to give their own name, submit a note giving the professor's name, the class number, section, date of the test, number of the question.
EmmaG, RN
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