IV math problem

metal_m0nk, BSN, RN · Aug 21, 2010

Yes, it is correct. However you may want to modify your process so that it is harder to get confused as problems get harder...

Since what you want to end up with is time, instead of starting off with mLs and using them to figure out time at the end, you might benefit from starting with time...

Figure out how much time has passed first...A rate of 100 mL/hr means if 642 mLs have already been infused, then 6 hr and 25 min have passed. Then use the total time (10 hrs) to determine how many hours you have left.

Does that make sense?

tcconnelly · Mar 5, 2011

I am lost in this problem can someone walk me through it?? You have on hand morphine 500mg in 500ml normal saline. You need to administer morphine 80mg/hours in a continuous IV infusion to a patient with terminal cancer pain. How many milliliters per hour will you set on the controller??

tokidokifantasy · Mar 5, 2011

Yes, it is correct. However you may want to modify your process so that it is harder to get confused as problems get harder...
Since what you want to end up with is time, instead of starting off with mLs and using them to figure out time at the end, you might benefit from starting with time...
Figure out how much time has passed first...A rate of 100 mL/hr means if 642 mLs have already been infused, then 6 hr and 25 min have passed. Then use the total time (10 hrs) to determine how many hours you have left.
Does that make sense?

wow!! I never thought of solving the problem that way. Our instructor taught us another way to calculate. It didn't see easier, but it made sense to me. I think it was administering food via NGT. order was for 1000ml of Jevity @ 50ml/hr, and the patient had about 168ml left and how much time is left? I think I learned it to divide 168ml to 50ml and then time 60min. But I like the way you did it. seems easy!! thanks!

~Mi Vida Loca~RN, ASN, RN · Mar 5, 2011

I am lost in this problem can someone walk me through it?? You have on hand morphine 500mg in 500ml normal saline. You need to administer morphine 80mg/hours in a continuous IV infusion to a patient with terminal cancer pain. How many milliliters per hour will you set on the controller??

I can never type math out but I will try.

You need to figure out mL/hr

You have:

500mL 80mg

-------- x -------- =

500mg hr

I helped you set it up, you need to do the math portion yourself, you multiply across on the top and the bottom, than you will take your top number and divide it by your bottom number. The mg cancel each other out leaving you will mL/hr

Hopefully that makes sense, I am much better at actually "showing" how to do it, than on line.

Ok, it's not wanting to align right when I actually post it, that should be 500ml over 500mg and than a multiple sign and 80mg over Hr