Need help on drug dosage problem

Published

Here is the problem:

A patient is admitted to your ICU with dopamine infusing at 13.5 mL/h. His weight is 75 kg. The dopamine concentration is 1 g in 250 mL of D5W. At what rate, in micrograms per kilogram per minute, is the dopamine infusing?

1000/250 x 13.5

---------------- = mg/kg

75

I think, lol.....do you have the answer?

The answer is 12, but I don't know how to get it.

The answer is 12, but I don't know how to get it.

me neither, lol.....my way would have been 720 mcg/kg......i think.....maybe try posting in the icu forum? our resident student assist nurse is not posting right now......and at least the icu nurses would have a clue what would be reasonable an perhaps be willing to help....good luck

Formula

Using the example above, first determine how many milligrams/hour is being delivered by the IV pump. The rate of the IV (cc/hr) is divided by the volume of the IV bag (mL available), then multiply this result by the total amount of medication (mg) in the IV bag.

rate

mL available

x dose available

becomes

53mL/hr

500mL

x 800mg

which = 84.8 mg/hr

Next, after the milligrams/hour has been determined, use the next formula to convert from milligrams/hour to mcg/kg/min.

mg

60min

x 1000 / kg

becomes

84.8mg

60min

x 1000 / 70

which = 20.2 mcg/kg/min

Specializes in Critical Care.

1000 mg dopamine in 250 mL.

You're giving 13.5 mL/hour.

Cross multiply this and you find that you're giving 54.16 mg an hour.

54.16 mg divided by 60 minutes in an hour divided by the patient's weight in kg yields 12 mcg/kg/min.

i just figured out i was on the right track, i didnt finish....720/60=12! darn, i thought i was totally losing it there for awhile!

Thanks everyone, you really helped me.

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