Math help!!!!!

[Eoo7l]

Ordered: 850 units/hr available: 10,000 units/ ml. How many mL of Heparin to add in 500mL NS for 24hr?
How would you set it up the pump in mL/hr?

[savingamericanhearts]

First of all, withdraw 2.5 ml from your 500ml bag of NS
then put 2.5ml of your 10,000 units/ml in that bag, now giving you 50 units of heparin for each ml in your 500ml bag of NS.
Now your total 500ml bag of NS has 25,000 units of heparin in it.

25,000units 850 units
------------- X -------------
500ml X ml

Cross multiply 25,000 X xml = 25,000X
and 500ml X 850 units = 425,000

425,000 divided by 25,000 = 17ml/hr on your pump (17mls of 50units/ml = 850 units)

17ml/hr x 24 hrs = 408 mls so you bag will last the full 24 hours

[Eoo7l]

First of all, withdraw 2.5 ml from your 500ml bag of NS
then put 2.5ml of your 10,000 units/ml in that bag, now giving you 50 units of heparin for each ml in your 500ml bag of NS.
Now your total 500ml bag of NS has 25,000 units of heparin in it.

25,000units 850 units
------------- X -------------
500ml X ml

Cross multiply 25,000 X xml = 25,000X
and 500ml X 850 units = 425,000

425,000 divided by 25,000 = 17ml/hr on your pump (17mls of 50units/ml = 850 units)

17ml/hr x 24 hrs = 408 mls so you bag will last the full 24 hours

I am confuse on the 2.5 mL to add to the bag that do first. I understand the rest of the steps but, I have no idea how you got the 2.5.
I really appreciate your help.

[starr-rn1]

ask pharmacy, that is there job!!!

[jayne1975]

The 2.5 isn't a specific number you have to use, but for the sake of making it easier to calculate
2.5ml = 25000 units of heparin
Adding it to the 500ml NS, gives you 50units of heparin per every 1ml solution.
(Pre-mixed heparin comes in that ratio when you don't have to mix it manually and most IV pumps are set with that concentration as the standard.)

[scotttyna]

The 2.5 isn't a specific number you have to use, but for the sake of making it easier to calculate
2.5ml = 25000 units of heparin
Adding it to the 500ml NS, gives you 50units of heparin per every 1ml solution.
(Pre-mixed heparin comes in that ratio when you don't have to mix it manually and most IV pumps are set with that concentration as the standard.)

You are right!!!