Question

The order is to infuse 150 mg of a drug in 1000 ml LR at 5 mcg/kg/min to a client weighing 60 kg (the drop factor is 20 gtt/ml)

Answer the question below.

a) What is the infusion time for the IV?

b) What is the rate of flow of the drug in mcg/min?

c) What is the flow rate for the IV?

Answer 1

Answer : a)  The infusion time for the IV is 8 hours 20 min

b)  The rate of flow of the drug in mcg/min is 300 mcg/min

c) The flow rate for the IV is 120 ml/hour

Order : infuse 150 mg of a drug in 1000 ml LR at 5 mcg/kg/min

Weight : 60 kg

Drop factor : 20 gtt/ml

a) Calculate the infusion time?

Now solve the problem to find infusion time using dimensional analysis

Step 1 : Find ml/min

ml/min = ( Cancel out kg, mcg and mg from numerator and denominator)

=  

= 2 ml/min

Step 2 : FInd infusion time in hours

Infusion time =     ( Cancel out ml and min from numerator and denominator)

=

= 8.333 hours ( ie 8 hours + 0.333 hours)

Step 3 : Convert 0.333 hrs in to minute

=   ( Cancel out hr from numerator and denominator)

= 19.98 min (ie round the answer as 20 min)

Infusion time = 8 hours 20 min

b) Calculate the rate of flow of the drug in mcg/min?

Doctors order is 5 mcg/kg/min

ie mcg/min =    ( Cancel out kg from numerator and denominator)

= 300 mcg/min

c) Flow rate for the IV?

Flow rate (ml/hour) =  

(From the infusion time calculation we know time in hours is 8.333 hours)

=

Flow rate = 120 ml/hour