Confused on Infusion Rate problem...

Hello All!
I'm a little confused on an infusion rate problem and was trying to seek some advice to point me in the right direction.
The problem states...
" The physician orders nicardipine hydrochloride (Cardene) 25 mg/250 mL, NS for peripheral IV starting at 2.5 mg per hour, and titrate by 2.5 mg per hour every 15 minutes to reach the goal for the first hour, which is to achieve 25% reduction of the initial MAP.
 Call the physician if the dosing range of 15 mg per hour has been reached and the MAP is still not at target goal for the first hour of treatment, or up to 4 dose increases.
 Lower the blood pressure within 6 hours to 160/100 mm Hg.
 Adjust the IV rate so that the IV fluids plus the nicardipine IV drip are equal to 100 mL per hour, in total. Call the physician if the IV fluids must go above 100 mL per hour to provide the nicardipine.
Explain what rate to initially set both the nicardipine drip and the NS maintenance fluids"
My drug book states to set the rate for Cardene at 50mL/hr? I guess I'm confused because it doesn't tell me exactly how much time to infuse it.
I'm completely confused about the normal saline for 2.5mg/hour.
Any advice is certainly appreciated.
Thanks 

Sep 7, '12Remember that all the info you need should be in the question. What rate does the question tell you to start with?

Sep 7, '12Quote from ashulee89You have 25mg of the drug diluted in 250mL of NS.I'm completely confused about the normal saline for 2.5mg/hour.
Any advice is certainly appreciated.
Thanks
You know how many mg/hr is ordered and the concentration (mg/mL) you have, so you now just have to calculate the rate (mL/hour).Last edit by BostonFNP on Sep 7, '12 
Sep 7, '12Thank you for the reply. After taking a well needed break to go work out and clear my head, I started to try and think in simpler terms. I came up with 25mg divided by 2.5mg/hr which equals 10 hours/ 250 mL. 250mL divided by 10 equals 25mL/hr. I hope I got it right this time. I was really trying to figure it out.
Since the physician ordered 100mL/hr of the total cardene and NS i subtracted 100mL/hr from 25mL/hr Cardene to equal 75mL/hr NS.
I appreciate your help 
Sep 7, '12You are correct. You went about the problem a little differently than I would have but your reasoning is valid.
This is how I would approach this problem:
You know you have 25 mg/250 mL of NS. This equal 1 mg/10 mL. You need to infuse 2.5 mg/hr x 10 mL/mg = 25 mL/hr. 