METHOD 3
Question: 
Dose calculation for Morphine in child weighing 3 kg. 
Dose is 20 microgram/kg/hour and you are given 1 ml 
ampoule containing 10 mg of Morphine. Use 0.9% Normal 
Saline if required for dilution. 
Calculation: 
Dose of Morphine=20 microgram/kg/hour 
Weight=3 kg 
Amount of Morphine required=3X20=60 microgram/hour 
In 1 ampoule, 1 ml contains 10 mg or, 10,000 microgram of Morphine 
So, 0.6 ml contains 6,000 microgram of Morphine 
Now, take 0.6 ml Morphine in a syringe and add 99.4 ml 
Normal Saline to make it 100 ml. 
In it 1 ml contains=6,000/100=60 microgram of Morphine 
Now, take this 100 ml Morphine solution in a Syringe 
driver and set it at a rate of 1 ml/hr. 


Child is 3kg 
Dose is: 20mcg/kg/hour 
So, the required dose is- 60mcg/hour 
For 24 hour- 60x24= 1440 mcg 
The 1ml morphine ampoule contains 10mg= 10000 mcg 
As we require only 1440 mcg out of this 10000 mcg, 
hence to be DILUTED- 

METHOD 1-add 1ml of morphine to 9ml of Normal Saline to make a solution of 10 ml which has a FINAL conc. of 1000mcg/ml. 
then take 1.44 ml of this solution which is = 1440 mcg . 
this is required for a period for 24 hours at a rate of 1ml/hour. 
eventually add 22.56 ml of NS to make it 24 ml ( which now has a conc. of 60mcg/ml ). 

METHOD 2- Add 1ml ( containing 10mg=10000mcg ) to 99ml of NS. 
This make a dilution of 100mcg/ml. 
required quantity is 1440 mcg for the 24 hour,
hence take 14.4 ml of this solution 
and add 9.4 ml of NS to make a 24 ml solution ( this now has a conc. of 60mcg/ml ).

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