I am in my third semester currently. Today I had my math calculation test. I didn't think it was too bad but i missed it by 1 question. So I need some help. I need to pass the test, otherwise I will not be able to pass medications in clinical. We have a math calculation test each semester. Here is the question I struggled with:
1.Questions that ask at what time should the medication end.
example: 1.An IV of 50 mL of D5W with Ancef 1 GM is to infuse at 100mL/hr. The IVPB started at 0730.
What time will the infusion end?
-How do we calculate these? I saw a similar question on my test for the first time and I put my answer as 0900 but the answer was 0920. What? How? Help? unfortunately, i don't remember the exact work problem but there must be formula or something.Does anyone know a website where I can find problems specifically like this one or can someone give me one to practice.
hmm. are we multiplying 1 hour by 60 then by 50. I get 3000
You then divide by the rate of infusion. Unfortunately, my dimensional analysis apparently doesn't format properly, so hard to show you how to lay it out on the computer.
Once you multiply it across, then you divide by the rate of infusion, so if infusing at 100 ml/hr, then it's 30 mins. If infusing at 125 ml/hr, then it's 24 mins. If it's infusing at 150 ml/hr it's 20 minutes, etc.
Hey guys! I think I know how to solve these problems now. I forgot the public libraries offered online tutoring, which I've used all throughout high school. I found myself reverting back to their assistance even in nursing school. but the way the tutor showed me how to solve it was: Rate=Amount/Time. The rate in this problem would be 100, the amount 50 ml, and time would be X. basically X will cancel, and what you do to one side you have to do to the other side. So I will be left with 100x=50 50 divided by 100 is .5. 0.5X60 minutes is 30 minutes. 0730 plus 30 minutes is 0800.
Another problem we worked on, and I'm writing this out just in case another nursing student might find this helpful.
Example of other problem: The order is 800 ml of D10W to infuse at 50 ml/hr start time is 0830. What is the completion time?
So rate is 50 ml/hr, amount is 800 ml, and time is X. Cross out X on both sides we are left with 50X=800. now divide 800 by 50 we get 16 hours.
0830 +1600=2430. Now, since its 24 hours in a day, the tutor said we could basically subtract 2430-2400=0030 so our time 00:30
Thank you everyone for your help. I really appreciate the time and effort and trying to get me to understand these problems. I am still on the hun for a website where I can find similar problems. I am retaking my math calculation next week. Hopefully, I pass this time. Thanks again everyone, You guys are great and nursing school is a little less difficult with the help of this website.
Always follow the labels!!! You will get the right answer every time. Remember chemistry?
Take the information (labels) you have and know what (label) you are trying to get. In this case you need to know how many hours.
The med infusing is 50 mL and the infusion rate is 100 mL/hour
50 mL x 1 hr = 0.5 hrs
100 mL
because you the mL cancel out, so if it will take 0.5 hours or a half hour and it was started at 0730 it will be done at 0800
Follow the labels and flip the "fractions" to cancel out the labels you don't need so you can end up with the ones you do need and then just multiply the top of the fractions first then divide by the total of the bottom.
I hope this helps. It makes PERFECT sense to me but I may not be explaining it properly.
Some medication calculations do not even require a formula to get the answer. 100ml/hr...so in 1 hour 100mls will infuse. You only have 50mls so it will only take half the time to infuse because it is half the amount. If you were infusing 100ml the infusion would end at 830, 50 mls is half that amount of time=8am. Don't over think some of these ;-)
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hmm. are we multiplying 1 hour by 60 then by 50. I get 3000