Can you solve this mcg to mg conversion?

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I was working at my Per Diem job yesterday. One of the acute care nurses came to me, baffled by an order for Fentanyl that read 100mcg/2ml give 0.025 to 0.05 mg. First of all, I think that's a dumb way for pharmacy to transcribe the order. But, nevertheless, I couldn't get this fellow to understand how much to give. He told me that he is usually good at math, but I kind of doubt it. I diplomatically walked him through it several times, not giving any hint that I thought he should know this. It's important for us nurses to be able to ask our co-workers to double check without them rolling their eyes.

So, allnurses cohorts, is this nursing 101 or is this a confusing order? Can you figure out how many ml to give?

Wow.. what a mess of an order. These are the orders that lead to overdoses.

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So, allnurses cohorts, is this nursing 101 or is this a confusing order? Can you figure out how many ml to give?

Yes, nursing 101. I was able to do the conversions in my head in just a few seconds. (I LOVE me some math!) As others have said, it is a poorly written order... ripe for the misplacement of a decimal point or two.

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Often when you get an answer in the "10cc" range, you've gotten a decimal point off.

Just sayin'.

The calculation was correct...but the prescription was clearly mistranscribed here. Does anybody know the usual dose range for fentanyl? Apparently not. That's the missing part of your anecdote.

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25 mcg or 50 mcg, 100 mcg/2 ml would be 1 ml for 50 mcg or 0.5 ml for 25 mcg. Just gotta move the decimal.

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Specializes in pediatric.

I was just glad I got the math right before I looked at the answers! ;) But I did use a paper and pencil...

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Specializes in Geriatrics, Dialysis.

Holy smokes! Math is kind of fun, but why on earth would an MD write an order, or the pharmacy dispense the med requiring the administering nurse to calculate a dose with a conversion from mcg to mg? That is a huge, and potentially dangerous med error just waiting to happen!

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Specializes in Med nurse in med-surg., float, HH, and PDN.

I can see it being a test question/problem in nursing school, but in "real life"?

The saying is that "numbers don't lie" , but they can sure get you gommed up !

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Specializes in Emergency/Cath Lab.

Stupid way to write it all around. Order it as mcg as thats what it comes in.

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an order for Fentanyl that read 100mcg/2ml give 0.025 to 0.05 mg.

A lot of people struggle with numeracy... Not math, per se but just a good sense of numbers.

Setting aside that fentanyl is probably (along with morphine) the med which I most often give and hence which dosing is second nature for me... I looked at this problem and solved it in less than 1 second simply by knowing that micro and milli are related by a factor of 1000 so 0.025-0.05 mg equals either 25-50 mcg OR 0.000025-0.00005 mcg... The latter of which is ridiculous...

I think we all agree that the order is poorly written but it's even before Nsg 101. I'd call it simple 5th grade common core maths.

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Specializes in Med nurse in med-surg., float, HH, and PDN.

Not in MY 5th grade class! :eek:

(1959; core meant the remaining part of the apple after you ate one.)

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Specializes in LTC, Psych, Med/Surg.

(1959; core meant the remaining part of the apple after you ate one.)

:laugh: :laugh: :laugh:

Catmom :paw:

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Specializes in Med/Surg, Ortho, ASC.
100 mcg to mg is 0.1

give 0.25 mg= (0.25*(2ml/0.1 mg)=5ml

give 0.5 mg= (0.5mg*(2ml/0.1mg))=10 ml

EEEK! 5-10 mls? I think not!

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