How do I recalculate flow rates for infusions?

[EmilyEmily]

1. An IV of 500mL was ordered to infuse in 3 hr using a 15gtt/mL set. With 1 1/2 remaining, you discover that only 150 mL is left in the bag. At what rate will you need to reset the flow?

2. An IV of 1000mL was ordered to infuse in 8 hr. With 3 hr of infusion time left, you discover that 600 mL have infused. The set delivers 20gtt/mL. Recalculate the drip rate, and indicate how many drops you will count in the 15 sec to set the new rate.

[akulahawkRN, ADN, RN, EMT-P]

1. An IV of 500mL was ordered to infuse in 3 hr using a 15gtt/mL set. With 1 1/2 remaining, you discover that only 150 mL is left in the bag. At what rate will you need to reset the flow? So you have 150 mL in the bag with 90 minutes to go, correct?

2. An IV of 1000mL was ordered to infuse in 8 hr. With 3 hr of infusion time left, you discover that 600 mL have infused. The set delivers 20gtt/mL. Recalculate the drip rate, and indicate how many drops you will count in the 15 sec to set the new rate. So you have 600 mL to be delivered over the next 3 hours...

You recalculate just as you would for an initial rate... only you plug in the amount you have left in the bag and how much time you have left. For question #2, you do the same and add in the number of gtts you will need to have per minute to ensure the rate is correct.

You're just overthinking this.

[EmilyEmily]

You recalculate just as you would for an initial rate... only you plug in the amount you have left in the bag and how much time you have left. For question #2, you do the same and add in the number of gtts you will need to have per minute to ensure the rate is correct.

You're just overthinking this.

Could you work it out?? I keep doing the steps over and over and getting the wrong answer

[EmilyEmily]

help please

[mariebailey, MSN, RN]

This may help: DosageHelp.com - Helping Nursing Students Learn Dosage Calculations

[EmilyEmily]

how come no one will illustrate how to solve the problem???

[Mina E.]

1. An IV of 500mL was ordered to infuse in 3 hr using a 15gtt/mL set. With 1 1/2 remaining, you discover that only 150 mL is left in the bag. At what rate will you need to reset the flow?

So you have 150ml to infuse over 90mins at a rate of 15gtt/ml

(150ml/90mins)(15gtts/ml)= 25gtts/min

2. An IV of 1000mL was ordered to infuse in 8 hr. With 3 hr of infusion time left, you discover that 600 mL have infused. The set delivers 20gtt/mL. Recalculate the drip rate, and indicate how many drops you will count in the 15 sec to set the new rate.

So you have 400ml of the 1000ml left to infuse at a rate of 20gtt/ml

(400ml/3hr)(1hr/60min)(20gtts/ml)= 44.4gtts/ml or about 44gtts/ml

Over 15secs, you would count 11gtts

[EmilyEmily]

Thank you so much for solving that for me. I really appreciate it

[Mina E.]

Thank you so much for solving that for me. I really appreciate it

I happen to be reviewing flow rates earlier today and thought I should give it a try.

[EmilyEmily]

So you have 150ml to infuse over 90mins at a rate of 15gtt/ml

(150ml/90mins)(15gtts/ml)= 25gtts/min

Wait I still don't see how you got 25 for this one..I'm getting 9

[Mina E.]

Wait I still don't see how you got 25 for this one..I'm getting 9

I am not sure how you how 9.

150/90=1.666

1.666x15=24.9 or 25.

Redo your calculations.

[akulahawkRN, ADN, RN, EMT-P]

Simple math. Do the stuff in parenthesis first, left to right...

150mL/90 min = 1.67 mL/min. Then multiply by the gtt factor.

1.67 mL/min * 15gtts/mL = 25 gtts/min.

As to why we weren't helping that much is that we generally prefer to point the way to the solution and if you follow the pointing, you'll arrive at the solution yourself and understand the result much more concretely than if we spoon feed you the answer.