# calculation question (HELP!!)

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today I had a pantoloc drip (8mg/hr) the nurse took one look at it and said the rate was 20ml/hr?

I have been busting my brain in trying to figure out how she got that, but I still don't know how. If some one could PLEASE PLEASE explain how she got the rate I will be FOREVER gratefu l:redbeathe

1,261 Posts

Specializes in LTC.

The dose of the med could be 8mg/hr. But since it was an IV.. IV's are in mL. Was the med an additive to the IV?

68 Posts

Rate of IV admin can be commonly expressed in dose/hour, or volume/hour, or dose/kg/hour.

If you were giving 8mg/hr, and she said it was 20ml/hour, and it was coming from say, 150ml bag, that just means the concentration in the bag was 60mg/150ml.

Does that make sense? I can break it down more if you need me to.

41 Posts

um, still don't understand.

It was a continuous pantaloc drip 40mg/10ml which was injected in a 100ml bag. and all that was written was 8mg/hr which equaled 20ml/hr? how did they get the rate of 20ml/hr?

68 Posts

So you had 40mg in 100ml. So, when you announced that the desired dosage was 8mg each hour, she was telling you that the pump would need to be set at 20ml/hr to deliver that dosage, becasue:

8mg x 100ml = 20ml

1hr 40mg 1hr

Make sense? 8mg/hour and 20ml/hour are the same thing in this case, because there are 8mg in each 20ml of solution. It's just expressing the dose in different terms of mass/time and volume/time.

We good?

41 Posts

lol, YES!!

thanks ALOT!!!:bowingpur

68 Posts

No sweat. Good luck.

allnurses Guide

3,796 Posts

Specializes in CTICU.

Yes, if you know there's 40mg in the 100ml bag, and you need to give 8mg/hr, then that's one-fifth of the bag per hour. So divide the 100mls by 5 and you get 20mls as your rate.

41 Posts

just to add on, didnt feel the need to start another NEW thread.

40mg (40mg|4ml) of lasix is in 50 ml bag the instruction says 4mg/min how do you calculate what rate to but for the IV?

1,023 Posts

Specializes in ICU.
So you had 40mg in 100ml. So, when you announced that the desired dosage was 8mg each hour, she was telling you that the pump would need to be set at 20ml/hr to deliver that dosage, becasue:

8mg x 100ml = 20ml

1hr 40mg 1hr

Make sense? 8mg/hour and 20ml/hour are the same thing in this case, because there are 8mg in each 20ml of solution. It's just expressing the dose in different terms of mass/time and volume/time.

We good?

Wouldn't the flow rate be 22ml/hr, rather than 20? Remember that the drug was in 10ml of diluent, and that 10ml was added to a 100l bag of IV fluid, for a total volume to be infused of 110ml?

Just checking....

41 Posts

no, because the 10 ml was taken directly from the 100 ml back.!!

890 Posts

50ml x 4mg x 60min = 12000 = 300ml

40mg...1min...1hr........40..........hr

I think this is right...anyone else?

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