Question

Mr. Smith is on Levophed drip (8mg/250mL D5W) infusing at 20 mL/hr. How many mcg/kg/min is he receiving if he weighs 80 kg? How man mcg/min?

Answer 1

Rate of infusion = 20mL/hr = (20/60)mL/min = 0.333mL/min.

( 1 hour = 60 minutes).

Concentration of infused solution = 8mg/250mL = (8*1000)mcg/250 mL = 8000mcg/250mL = 32mcg/mL.

( 1 milligram = 1000 microgram).

Concentration = mass /volume.

Mass = concentration * volume = 32*0.333 = 10.666 mcg.

Rate of infusion = 0.333mL/min = 10.666mcg/min.

Weight of patient = 80 kg.

Rate of infusion per kg = rate/weight = 10.666/80 = 0.1333mcg/kg/min.

Hence the patient is receiving 0.133mcg/kg/min of levophed and the rate of infusion is 10.666mcg/min.