# Medication Calculation Help

- 0Jun 15, '06 by buddhababy2monsterHi, I need help! This question seems simple but I'm not grasping it. I know the answer is 120 ml/hr but I have no idea how to get to this. The question is :

Medication order: titrated medication 15 units in 500 ml. Infuse at 0.06 U/min. How many ml per hour needed to infuse to deliver 0.06 U/min? Any help is greatly appreciated!! - 0Jun 15, '06 by riverguyfirst you figure how many ml=.06units by using the equation dose desired divided by dose on hand times mls of solution on hand. That is .06units/15units x 500ml=2ml so then .06units/min = 2ml/min of the 500ml solution bag. You then multiply the 2ml/min x 60, because there are 60 min in 1 hour and you get 120ml/hr. Hope that wasn't to confusing.
- 0Jun 15, '06 by mimibearOkay, I have not done this for nursing school yet, but I am good at math. I am sure there are many correct ways to do this - here is mine. You know you have 15units in 500 ml, so each 1 ml has .03 u (15/500). To infuse .06 units a minute you need to infuse 2ml a minute (.03 x 2 = .06) so 2ml/min x 60 minutes an hour = 120 ml.

Hope you were able to follow that - good luck! - 0Jun 15, '06 by
*EricJRN*If there are 15 units in 500 mL, then there is 1 unit per 33.3 mL. (500 mL divided by 15 units = 33.3 mL/unit)

In one minute, we want to give 0.06 units. How many mL is that? Since we know that there are 33.3 mL in one unit and we want to give 0.06 of a unit, we can multiply 33.3 * 0.06, which equals 2 mL (or really close to it).

So we know we need to give 2 mL/min to get the 0.06 units. But the question asks for mL/hr. We know that there are 60 minutes in an hour, so we'll multiply 2mL/min * 60 min to equal 120 mL/hr.

If it doesn't make sense for you to talk it out like this, there's another technique called dimensional analysis that you can use. Look up dimensional analysis on a Google search for more information. Because it involves placing one value over another and cancelling, it can be a little tricky to illustrate on a forum like this. - 0Jun 15, '06 by
*Daytonite*By__dimensional analysis__(or factor label method where you end up factoring out the labels on your numbers so you end up with the correct labels in the right ratio):

**0.06 units / 1 minute**(dose desired)**X 60 minutes / 1 hour**(conversion factor)**X 500 mL / 15 units**(dose on hand)**= 1800 mL / 15 hr**(after multiplying all numbers and factoring out labels)**=**(final answer)__120 mL / 1 hr.__ - 0Jun 16, '06 by buddhababy2monsterThanks for all your help, I understand how you get to the answer now. It's great seeing the different ways to come up with the right one. Wish me luck on my quiz!
- 0Jun 16, '06 by
*Daytonite*Neostsigmine 1:2000 refers to it's dilution. 1:2000 means there is 1 gram of neostigmine in each 2000 mL of solution. By dimensional analysis (factor label method) the solution to the problem is obtained this way:

**0.5mg / 1**(dose desired)**X 1 gram / 1000 mg**(conversion factor)**X 2000 mL / 1 gram**(dose on hand)**= 1000 mL / 1000**(unreduced answer)**=**(final answer, one dose)__1 mL__

You will give 1 mL t.i.d.