Need Help with Pit/Mag Calculations

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So, we have another doseage calculation test tomorrow & Pit / Mag rates will be on this one. I'm pretty confident in saying that we never went over these & they are not in the Calculate with Confidence text that we use. Can someone, anyone, show me how to work these 2 problems? Thanks in advance!!!!

Doc Orders: Pitocin 4mU/min/IV infusion

Available: Pitocin 10 units in 250 mL NS

What is the IV flow rate?

Doc Orders: Terbutaline 5 mg/500 mL NS to infuse at 10 mcg/min.

What is the IV flow rate?

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Doc Orders: Pitocin 4mU/min/IV infusion

Available: Pitocin 10 units in 250 mL NS

What is the IV flow rate?

We know the Iv flow rate is in ml/hr so start with that on the left hand side.

ml/hr = 250ml/10units x 4mU/min x 60min/hr (this is a conversion) x 1 unit/1000mU (conversion)

Cancel out the labels on the top from the bottom and you are left with ml/hr

Answer is 6 ml/hr

Doc Orders: Terbutaline 5 mg/500 mL NS to infuse at 10 mcg/min.

What is the IV flow rate?

ml/hr = 500ml/5mg x 10mcg/min x 60 min/hr x 1 mg/1000mcg

Cancel out the labels on the top from the bottom and you are left with ml/hr

Answer is 60ml/hr

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Specializes in Emergency!.

I concur with newRN09. I didn't do it the exact same way but I got the same answers.

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Specializes in med/surg, telemetry, IV therapy, mgmt.

doc orders: pitocin 4mu/min/iv infusion

available: pitocin 10 units in 250 ml ns

what is the iv flow rate?

you must know that 1 unit of pitocin (oxytocin) is = to 1000 mu. the problem does not specify if the flow rate is to be in ml/minute or ml/hour (this would be on an iv pump).

by dimensional analysis. . .
4 mu/minute
(dose desired)
x 250 ml/10 units
(dose on hand)
x 1 unit/1000 mu
(conversion factor)
x 60 minutes/1 hour
(conversion factor)
=
6 ml/hour
(flow rate on an iv pump)

doc orders: terbutaline 5 mg/500 ml ns to infuse at 10 mcg/min.

what is the iv flow rate?

you must know the conversion 1000 mcg = 1 mg.

by dimensional analysis. . .
10mcg/minute
(dose desired)
x 500 ml/5 mg
(dose on hand)
x 1 mg/1000 mcg
(conversion factor)
x 60 minutes/1 hour
(conversion factor)
=
60 ml/hour
(flow rate on an iv pump)

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Thanks everyone for all the responses. I am able to work the rest of these problems using this method. However, if anyone out there knows another method to solve the pitocin question I would be interested in seeing it. I am a proportion girl & would love to understand where I was getting caught up. Thanks everyone:wink2:

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