IV Push

We gave our first IV push med today....I used a formula and my calculator to figure the IV push rate and it was correct.

However, our instructor wanted us to figure it in our head using the marks on the syringe. We used 3 mL syringe which is 30 marks.

The question is if you have drawn up 50mg/mL diluted with 3 mL NS (we gave Demerol) and you only want to give 12.5mg how do you do this in your head?

Add 3cc of NS to the 1cc of Demerol and you come up with a total concentration of 50mg per 4cc or 12.5mg per 1ml.

Once you know your concentration all you have to do is divide 50mg by 4cc.

I just keep halving everything, 50mg/3ml: 25mg/1.5ml : 12.5mg/ 0.75ml

That works too, but you need to add the 1ml of Demerol to the 3ml of NS 1st.

50mg/4cc: 25mg/2cc: 12.5mg/1cc etc.

OP said she used a 3cc syringe, I took that as including the demerol since I figured 4cc's wouldn't fit in a 3cc syringe, whatever , I divide total volume, halving it, pretty simplistic, I don't calculate out (hard copy) something I've done a zillion times, and simplistic at that, I do think a student and new nurse should until she is competent/comfortable/experienced.

I think I'm competent to do simple math, others may never trust their own judgment and may choose to calc out, I never see this among the seasoned nurses with common meds we do over and over every day

OOO....Ouch.....approriate screen name....

"The question is if you have drawn up 50mg/mL diluted with 3 mL NS (we gave Demerol) and you only want to give 12.5mg how do you do this in your head?"

By the way I just looked at the last part and if you dilute it with 3 more mls it works out the way I did it. I wasn't evaluating how competent your math skills are. So are we talking about diluting w/ 3cc of NS first or just mixing Demerol in a 3cc syringe there obviously is a big difference.

I don't think there is an argument here just a good point on how easy it is to make a med error on math calculations.

We gave our first IV push med today....I used a formula and my calculator to figure the IV push rate and it was correct.

However, our instructor wanted us to figure it in our head using the marks on the syringe. We used 3 mL syringe which is 30 marks.

The question is if you have drawn up 50mg/mL diluted with 3 mL NS (we gave Demerol) and you only want to give 12.5mg how do you do this in your head?

Use the formula: Dose desired divided by dose on hand: 12.5/50mg x 3 mL = 0.75 mL (amount to give). You'll only push 7.5 of those 30 marks on the syringe of the contents of the syringe.

However, I would never, in practice, do that. I've been a licensed RN for 32 years. It's too dangerous. The possibility of overdosing the patient by accident is too great. And, you can tell your instructor I said that.