# med calc help

1. Hi there, well its been a while since doing med calcs and would love to get some assistance with these two drug calcs please. If you dont use it you lose it. Appreciate your help, thanks

Mrs Rogers has had a CABG and is commenced on IVI Fentanyl

Order states to administer a bolus dose of 50mcgs Fentanyl IV diluted to 10ml in Normal Saline. Available 100mcgs/1ml. How many mls of Fentanyl will you draw up?

The Fentanyl infusion order states to dilute 500mcgs of Fentanyl in 50ml of Normal Saline for injection. Calculate the concentration (mcg/ml) of Fentanyl in Syringe.

The Fentanyl is commenced at a rate of 20mcg/hr. At what rate (ml/hr) will you set infusion pump to?

After 3 hours the patient states they have a pain score of 7/10. Order states that you can adjust rate between 20mcg - 80mcg/hr. You decide to increase the rate to 40mcg/hr and ask another RN to check your rate change. At what rate will you be setting the pump to?
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A patient has a Morphine infusion running at 4mg/hr . The additive label on the infusion reads:

Drug: Morphine
Dose: 25mg
Made up to 50ml with Normal Saline

What is the concentration of the infusion ( mg/ml)

How many ml/hr is the infusion running at?

The patients pain has decreased so the doctor orders to run the infusion at 6ml/hr

How many mg/hr is patient now receiving?
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3. I will not do these for you because I feel as an RN you should be able to do them; however I will tell you to think about the information:

What you have: How many Mcg per ML

What you need to give: How many mcg in bolus or per hour.

Swtooth
4. Thanks Sawtooth.

Well I have worked on all the Fentanyl and most of the Morphine. The last question of morphine i am stumped, trying to figure out what I do to reduce the rate?

i dont think I have come across a formula for this?

Thanks
5. You should be able to do these without a formula since the numbers are so small.

Morphine is 25 mg per 50 ml. That is 1 mg per 2 ml.
if you want a 4 mg/hour dose, you will run it at 8ml/hr
If you decrease to 6 ml /hr you will be giving 3 mg of morphine/hr.
Last edit by nservice on Mar 21, '07 : Reason: Read the question wrong...It's late!!