# Convert mcg/kg/min to mL/hr

## Formulas

First, convert micrograms per kilograms per minute (mcg/kg/min) to milligrams per hour (mg/hr).

$\frac{O×W×\mathrm{60 min}}{1000 mcg}$
• O = Dose ordered (mcg)
• W = Weight (kg)

Then use the dosage formula to calculate rate.

$\frac{O×V}{A}$
• O = Dose ordered
• V = Volume of dose available
• A = Dose available

## Examples

1. Dr. Smith wants a dopamine drip started at 20 mcg/kg/min on John Doe in Bed 7.  John Doe's weight is 70 kilograms (kg).  He wants an 800 milligrams (mg) vial of dopamine mixed in 500 milliliters (mL) of D5W.  First, convert (mcg/kg/min) to (mg/hr).

• Dose (mcg) = 20 mcg
• Weight (kg) = 70 kg
$\frac{\mathrm{20 mcg}×\mathrm{70 kg}×60 min}{1000 mcg}$

The answer is 84 mg/hr. Then use the dosage formula to calculate rate.

• Dose ordered = 84 mg
• Volume of dose available = 500 mL
• Dose available = 800 mg
$\frac{\mathrm{84 mg}×\mathrm{500 mL}}{\mathrm{800 mg}}$

2. Start a Nipride® (nitroprusside) infusion at 2 mcg/kg/min for a patient in hypertensive crisis. Pharmacy has sent 500 mL of D5W containing 50 mg of Nipride®. The patient weighs 160 pounds (lb). First convert pounds into kilograms by dividing pounds by 2.2.

$\frac{\mathrm{160 lb}}{2.2}$

160 lb = 72.7 kg. Next, convert micrograms per kilograms per minute (mcg/kg/min) to milligrams per hour (mg/hr).

• Dose (mcg) = 20 mcg
• Weight (kg) = 72. 7
$\frac{\mathrm{2 mcg}×\mathrm{72.7 kg}×60 min}{1000 mcg}$

The answer is 8.72 mg/hr. Then use the dosage formula to calculate rate.

• Dose ordered = 8.72 mg
• Volume of dose available = 500 mL
• Dose available = 50 mg
$\frac{\mathrm{8.72 mg}×\mathrm{500 mL}}{\mathrm{50 mg}}$