Question about infusion rate and time

by Jose
(Miami,FL USA)

I'm stuck on this question and cannot figure it out for the life of me:
Please help.

An IV has been ordered to run at 2.5 gtts/min. The IV contains 875 mg of drug in a total of 250 ml. How many mg of drug will be given to the patient per hour if the IV is to set to deliver 15 gtts/ml?

A. 25 mg/hr

B. 35 mg/hr

C. 45 mg/hr

D. 55 mg/hr

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Question about infusion rate and time

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Aug 16, 2011
TD VA tic-tac-toe?
by: Anonymous

30 5 parts of 30%
15 20 parts of 15%

25 total parts
5/25= 0.2
0.2 x 2500 ml= 500 ml of 30%

2500 ml - 500 ml= 2000 ml of 15%

Jun 30, 2011
Answer to Infusion Rate and Time Question
by: Anonymous

(875mg/250mL) x (1ml/15gtt) x (2.5gtt/1min) x (60min/1hr) = 35 mg

Mar 21, 2011
I'm stuck with this question , please help ..Thanks
by: TD VA

How many ml of 30% acetic acid must be mixed with 15% acetic acid to give 2500 ml of 10% acetic acid ?

Mar 15, 2011
Here is the solution
by: Anonymous

ml/hr = gtt/min X 60 / factor

= 2.5 X 60 / 15
= 10ml/hr

875mg/ 250ml = 3.5 mg/ml

3.5mg/ml = Xmg/ 10ml
X = 3.5 X 10
X = 35mg
Answer is: 35mg/hr

Feb 24, 2011
That's the correct answer, yes.
by: Keith

The best way to approach this type of question (besides neatly writing out each factor) is to do it in pieces. So, first figure out how many drops will drip in the hour.

2.5 per min X 60 min = 150 drops/hr.

I usually circle the answer and it becomes a new factor.

Then, determine how many mL those drops make up.

150 drops per hour/15 drops per mL = 10mL/hour

Now, using the ratio of the solution provided, do a quick proportion math to see what's in 10 mL.

875mg - - - X -
______ = ________
250mL - - 10mL

X = The answer to how may mg/hr of the drug will be infused.

Feb 24, 2011
by: Anonymous

I got 35 mg per hour.

2.5/15=0.166 ml per min=10ml per hr
875/250=3.5 mg per ml
3.5mgx10ml per hour=35mg per hour

I hope it is right! (I take my test today!)

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