# IV calculation

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by Lelele10 (New Member)

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The patient is receiving 150ml/hr x 8 hours and then is to be switched to 1/2 NS 500ml in 4 hours.

What is the total number of mls that patient received in IV solution?

What is the rate of flow in ml/hr for 1/2 NS to be set?

1700ml

However I'm not too sure about the answer for the second part...

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4 Followers; 17,715 Visitors; 2,727 Posts

You're over-thinking this. You need to get 500ml of fluid in in 4 hours. It's simple math. Try again.

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67 Visitors; 7 Posts

I may be over thinking it.

Is the patient getting the fluids in 4 hours..

So it will still run over 8 hours? Or is it just running for 4 hours?

Edited by Lelele10

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0.9%NormalSarah is a ADN, RN and works as a MICU RN.

345 Visitors; 78 Posts

Look at this as two separate orders.

1. You have 150mL per hour infusing for 8 hours.

Then you will change over to the new order after that one is complete.

2. You have 500 mL you need to give over 4 hours.

To answer the first part of the question, you are correct that you will give a total of 1700 mL. When you’re doing your dosage calculation problems, remember to approach them as steps. Here you actually have two orders, independent of each other, with the second one to run after the first is finished. So now try and work it out and what do you get for the second part of the question?

Edited by 0.9%NormalSarah

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If you are using regular tubing, then you find the rate with this formula:
volume / time in hours

For drip tubing:
volume * drip factor / time in minutes

The first part of the question is asking you to find the total volume of fluids the pt has been given in 12 hours.  The second part is asking you to find the rate of administration of 500 mL during the last 4 hours.

You're going to have to memorize formulas in order to do med math.  If you don't have the book "Calculate with Confidence," I recommend it.  You can get it for a good price used.