FOR FENTANYL

calculate the Dose for Fentanyl 
its dilution volume for 24 hours if given at a rate of 1 ml per hour 
the ampoule has 0.5 mg/ml. 
Weight of pt 25 kg 
the requisite dose was 4 microgram/kg/hour. 


Dose of Fentanyl = 4 microgram/kg/hr 
Weight of baby= 25 kg 
Amount of Fentanyl required = 25X4 =100 microgram/hr 
So, total amount of Fentanyl required in 24 hours = 100X24 =2400 microgram 

In the ampoule, 1 ml= 0.5 mg or 500 microgram Fentanyl 
Now, 500 microgram Fentanyl is present in 1 ml 
1 microgram Fentanyl is present in 1/500 ml 
2400 microgram Fentanyl is present in 1X2400/500 ml= 4.8 ml 

Now,as per the problem Fentanyl solution is to be run at a rate of 1 ml per hour for 24 hour. 
So, total amount required to be given in 24 hours = 1X24= 24 ml 
Hence, amount of Normal saline to be added= 24-4.8 ml= 19.2 ml 

Amount of Normal saline to be added is 19.2 ml