PICU - mcg/kg/min questions

Okay, here's how we do it. Although, our IV pumps are smart pumps, and that cuts WAY back on med errors.

Let's say you are going to start a dopamine gtt on a 10kg patient. The order reads:

"dopamine 5mcg/kg/min"

your concentration is 3200mcg=1cc

here's the math:


(dose ordered) X (pt weight in kg) X (minutes)
__________________________________________ = (rate of pump)

(amount of mcg in 1cc)


OR:

5 X 10 X 60
-------------- =0.9375cc/hr
3200

Hope that helps!

Oh, and the rate of the pump will always run as cc's/hr, even if your med is ordered minutes. Dopamine, epi, norepi, pressors always ordered mcgs/kg/min. Other gtts such as bumex, lasix, morphine, versed, always orders in hours. It seems like a lot of info, I'm sure, but as you use it every day, you'll get it. Congrats on your new job!

Hey that was a good answer, Kessa! I would have given a slightly longer one, but basically the same once the units are cancelled out:

mcg/kg/min x kg = __ mcg/min, then:
__ mcg/min x 60min/hr x cc/mcg = cc/hr

5mcg/kg x 10kg = 50mcg, then:
50mcg/min x 60min/hr x 1cc/3200mcg = 3000cc/3200mcg = .937 cc/hr.

This way you see right away where all the units went and you know you have the right units at the end before you even plug in the numbers.

NSUNurse,

Not a dumb question at all!

Our gtts are figured using a standard concentration book. The concentration of each drug depends on the weight of the patient, 5kg or less, 5- 20 kg, or 20kg or greater, I think. For example, we mix a versed gtt for a larger child using a 1mg=1cc concentration, but for a 2 kg baby it would be 0.5mg=1cc. 3200mcg=1cc concentration for dopamine is a standard premix for dopamine at my facility, used for the bigger kids. The only variation on these formulas in the book comes when you have a patient on strict fluid restriction, then our attending can write orders to concentrate the gtts even further.