mcg/kg/min to mL/hr Calculator

kg

The bag as it was made up

mg
mL

Read this off the label on the bag after it was mixed, not off the ampoule.

Pump rate

mL/hr

Enter a dose rate and the bag it is running from.

Bag strength
Dose delivered

The working

    This works out the arithmetic. The order, the product in your hand and local policy still govern what is given.

    How to convert mcg/kg/min to mL/hr

    mL/hr = (dose rate × weight) ÷ bag strength in mcg/mL × 60

    Three steps. The dose rate times the weight gives micrograms a minute. The drug in the bag, in micrograms, divided by the bag volume gives the strength per millilitre. Dividing one by the other gives millilitres a minute, and multiplying by 60 gives the hourly rate a pump takes.

    A 70 kg patient at 5 mcg/kg/min from a bag of 400 mg in 250 mL runs at 13.13 mL/hr, because that bag holds 1600 mcg in each millilitre.

    The bag strength changes the pump rate, not the dose

    Same patient, same order, two different bags:

    BagStrengthPump rateDose delivered
    400 mg in 250 mL1600 mcg/mL13.13 mL/hr5 mcg/kg/min
    200 mg in 250 mL800 mcg/mL26.25 mL/hr5 mcg/kg/min

    The patient receives exactly the same dose in both rows. Only the volume carrying it has changed. This is why a pump rate copied from a previous shift is unsafe unless the bag it was calculated against is the bag now hanging, and why the calculator asks for the made-up bag rather than the ampoule strength.

    For an infusion with no weight term and no dose rate, the plainIV flow rate calculator is the simpler tool.

    Questions about dose rates

    How do I convert mcg/kg/min to mL/hr?
    Multiply the dose rate by the weight in kilograms to get mcg per minute. Work out the bag strength in mcg per mL by multiplying the drug in mg by 1000 and dividing by the bag volume. Divide the first by the second and multiply by 60.
    What is the difference between a dose rate and a pump rate?
    A dose rate says how much drug the patient receives over time, in units like mcg/kg/min. A pump rate says how much liquid is delivered over time, in mL/hr. A pump only understands the second, so a dose rate has to be converted using the strength of the made-up bag.
    Why does the same order give a different pump rate on a different bag?
    Because the amount of drug in each millilitre has changed. The patient still receives the same dose; the volume carrying it is different. This is why the bag strength has to be confirmed rather than assumed when a rate is checked.