Infusion pump dosage calculation

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Order: Dopamine 5 mg/kg/day IV q4h in 120 mL of D5W over 1 hour.

On Hand: Dopamine IV 20 mL vial with 10 mg/mL.

Patient weights 135 lbs

Dilute the desired dose in 120 mL of D5W

Calculate the flow rate in ml/hr for the infusion pump:________________________

What I know so far:

135 lbs is 61.36 kg

Order by mg/dose:

(5mg/kg/day) X (61.36 kg) X (1 day/6 doses) = 51.14 mg/dose

lost from here:

To begin with, this is a ridiculous problem as dopamine is not administered as an IV bolus; rather it is administered as a continuous infusion. Having said that, this is the format that you would use to calculate dosages for many medications, so let's finish the calculation.

Order by mg/dose:

(5mg/kg/day) X (61.36 kg) X (1 day/6 doses) = 51.14 mg/dose

This is correct for a single dose. From here you only have two more steps.

How many mL of dopamine do you need to draw up for your desired dose?

Add this volume to the required volume of diluent, this will be your hourly infusion rate.

Sweet jaysus, Dopamine isn't dosed in mg/kg/day, it's mcg/kg/min. This is a nutty problem. You give 51 mg as a "dose" and you'll never have to give a second one. :)

Specializes in NICU, PICU, PACU.

Sweet baby Jesus, who is making up these problems???? Obviously someone who has never infused Dopamine!

Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.
Order: Dopamine 5 mg/kg/day IV q4h in 120 mL of D5W over 1 hour.

On Hand: Dopamine IV 20 mL vial with 10 mg/mL.

Patient weights 135 lbs

Dilute the desired dose in 120 mL of D5W

Calculate the flow rate in ml/hr for the infusion pump:________________________

What I know so far:

135 lbs is 61.36 kg

Order by mg/dose:

(5mg/kg/day) X (61.36 kg) X (1 day/6 doses) = 51.14 mg/dose

lost from here:

Your math is good ...the question is crazy. I know I have said in the past that it's about the calculation of the med......but this med just cannot be administered in this manner.

Now you need to figure how many ml's of your drug (Dopamine 10mg/ml in a 20ml vial) is needed to be used to add to the diluent (120ml D5W)

But in the end if your med is diluted in 120ml D5W and needs to infuse over an hour your pump would be set at........ How many? ml's per hour.

Just remember that dopamine is NEVER infused this way.

http://www.dosagehelp.com/

Yeah, and print this out and tell your faculty we think it's an exceptionally bad idea to use examples that are improbable or unsafe :nono: , because someday someone will remember it and think it's OK. You can tell them I said so. (And yes, I have taught a lot of med math in nursing school.)

Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.

it is CRAZY that they would put this as a question.....someone is going to say I learned this in nursing school! and kill someone....unbelievable..:banghead:

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