Help with Dosage!

Boog'sCRRN246, RN · Jul 13, 2011

You might want to go back and edit your post to include what calculations you've already attempted.

ckh23, BSN, RN · Jul 14, 2011

What have you come up with so far? We are here to help you, but we are NOT going to do your homework for you.

LadyinScrubs, ASN, RN · Jul 14, 2011

What is it that you are having problems with.

Do you understand how to work the problem

or

have you worked the problems and have a different answer than the book?

Double-Helix, BSN, RN · Jul 16, 2011

Sounds like you might be having trouble with conversions. Here are some basics that it is good to memorize. You will use them endlessly.

1. 1g=1000 mg

2. 1 mg = 1000 mcg

2. 1kg = 2.2lb.

3. Lbs/2.2 = kg

4. Dosage calculations are D / H x V. Desired amount (D) divided by the amount you have on hand (H) multiplies by the volume the med is supplied in (V). V could be the volume of an IV solution, the number of pills, or a liquid medicine concentration.

Ao here are some tips for your specific questions:

1. First calculate the patient's weight in kilograms. Plug that number into the rate of your drip to calculate how much medication you would give in one hour.

2. For this problem, you know there are 250mls of fluid for 175 mg. You need to know how many mls of fluid there is in 10mg of medication. Do this by cross multiplying the concentration that you have and the concentration that you want. 175/250 cross multiplied with 10/x. Solve for x.

3. Convert dopamine mg into dopamine mcg. Then find out how much domapine is in one ml of the fluid. Then calculate how many mcg of dopamine the patient is getting per hour if the rate is 28mls. Compare this to: Find the patient's weight in kgs. Plug this into your formula 10mcg/kg/hr) and find out how many mcg of dopamine the patient should be receiveing per hour. Compare this to your first answer. Are they the same?

4. Very similar to number 3 but you don't need the patient's weight.

Hope this helped. In the future when you post questions like this, include the answer that you came up with as well as some information about how you tried to solve the question. Then we can more easily help you correct your mistakes. I'm happy to help, but I will not just give you the answers to questions. Otherwise, you are not learning anything.

ParkerBC,MSN,RN, PhD, RN · Jul 16, 2011

1. Convert weight from lbs to kg:

95lbs/2.2kg/lb = 43.2kg

mg/hr = 0.7mg x 43.2kg = 30.2mg/hr

mg/min= 30.2mg/hr / 60min/hr = 0.50mg/min

ml/hr = 1000mg = 30.2mg

1000ml X

1000X = 30,200

1000 1000

X = 30.2ml/hr

2. Set up as a ratio like part 3 in problem # 1

175mg = 10mg

250 ml X

175X = 2500

175 175

X = 14.3ml/hr

3. 10mcg/kg/hr = 0.010mg/kg/hr

The patient weighs 130lbs or 130lbs/2.2lbs/kg = 59.1kg

0.010mg X 59.1kg/min = 0.6mg/ min

0.6 X 60 = 36mg/hr (converted the above from mg/min to mg/hr)

Now you have to set up a ratio to see if the pump is set correctly.

400mg = 36mg

500 ml X

400X = 18000

400 400

X = 45ml/hr

So, NO…28ml/hr is wrong. The pump should have been set on 45ml/hr.

4. mg/hr Okay….you have 110mcg/min. This needs to be converted to mg/hr. So, 110mcg is the same as 0.110mg. 0.110mg X 60 = 6.6mg/hr. Since the original question stated mcg per min…you have to multiply by 60 to convert to hour.

ml/hr. You have to perform a ratio again.

250mg = 6.6mg

250ml X

250X = 1650

250 250

X = 6.6ml/hr. If the pump is infusing at 12ml/hr, it is running too fast. The correct infusion rate should be 6.6ml/hr.

I hope this helps…if not, respond and I will be happy to explain the steps.

ParkerBC,MSN,RN, PhD, RN · Jul 16, 2011

Sounds like you might be having trouble with conversions. Here are some basics that it is good to memorize. You will use them endlessly.
1. 1g=1000 mg
2. 1 mg = 1000 mcg
2. 1kg = 2.2lb.
3. Lbs/2.2 = kg
4. Dosage calculations are D / H x V. Desired amount (D) divided by the amount you have on hand (H) multiplies by the volume the med is supplied in (V). V could be the volume of an IV solution, the number of pills, or a liquid medicine concentration.
Ao here are some tips for your specific questions:
1. First calculate the patient's weight in kilograms. Plug that number into the rate of your drip to calculate how much medication you would give in one hour.
2. For this problem, you know there are 250mls of fluid for 175 mg. You need to know how many mls of fluid there is in 10mg of medication. Do this by cross multiplying the concentration that you have and the concentration that you want. 175/250 cross multiplied with 10/x. Solve for x.
3. Convert dopamine mg into dopamine mcg. Then find out how much domapine is in one ml of the fluid. Then calculate how many mcg of dopamine the patient is getting per hour if the rate is 28mls. Compare this to: Find the patient's weight in kgs. Plug this into your formula 10mcg/kg/hr) and find out how many mcg of dopamine the patient should be receiveing per hour. Compare this to your first answer. Are they the same?
4. Very similar to number 3 but you don't need the patient's weight.
Hope this helped. In the future when you post questions like this, include the answer that you came up with as well as some information about how you tried to solve the question. Then we can more easily help you correct your mistakes. I'm happy to help, but I will not just give you the answers to questions. Otherwise, you are not learning anything.

I agree with you to a certain extent. Generally with math, I know I need to see the problems worked out so that I can see where the steps come into play. If I don't understand the steps, then I can work the problems backwards to understand.

ckh23, BSN, RN · Jul 16, 2011

I agree with you to a certain extent. Generally with math, I know I need to see the problems worked out so that I can see where the steps come into play. If I don't understand the steps, then I can work the problems backwards to understand.

What Ashley, and everyone else, was trying to say that we can be more help to the OP if they posted their answer and where they are having trouble. The OP just listed their homework questions straight from the book with nothing else and appears that the OP wanted the work done for them, for which you kindly obliged them and did EVERYTHING for them. We are here to help these students, not to do their homework for them.

Double-Helix, BSN, RN · Jul 17, 2011

I agree with you to a certain extent. Generally with math, I know I need to see the problems worked out so that I can see where the steps come into play. If I don't understand the steps, then I can work the problems backwards to understand.

I explained the formula and the steps that the OP needed to take to answer the questions. He/she is free to respond again if they still have questions. If a person just posts there homework questions, receives a full answer and copies that answer they then get a 100 on their homework but learn nothing and may not be a safe nurse. So that's why I explain the formula and the steps using variables or examples. I'm not going to just go the OP's homework questions knowing there is a (good) chance they will just take the answers.

Of course, it's totally up to you if you want to do the homework questions for the poster.

ParkerBC,MSN,RN, PhD, RN · Jul 17, 2011

I have recently started teaching Dosage Calculations to nursing students. It is my experience that simply giving hints doesn’t help the students to learn. People become good at math by practicing the problems. It is kind of hard to do if you don’t know where to start. To say that the OP came to the site and posted problems to simply have someone else to do the work for her/him is premature. You don’t know that for certain. The story sounds similar to the ED nurses suggesting that patients who come into the ED with back pain are drug seekers.

Perhaps you are correct. Maybe the OP wanted someone to do the work. If that is the case, then I suppose I am the sucker. I don’t care if the OP gets a 100% on her/his homework without doing the work. That is on her/his conscious. I answered the questions…what the OP does with the information is no longer my concern. Quite honestly, after reading the steps posted of how to solve the problems, I was confused.

ckh23, BSN, RN · Jul 17, 2011

I have recently started teaching Dosage Calculations to nursing students. It is my experience that simply giving hints doesn’t help the students to learn. People become good at math by practicing the problems. It is kind of hard to do if you don’t know where to start. To say that the OP came to the site and posted problems to simply have someone else to do the work for her/him is premature. You don’t know that for certain. The story sounds similar to the ED nurses suggesting that patients who come into the ED with back pain are drug seekers.
Perhaps you are correct. Maybe the OP wanted someone to do the work. If that is the case, then I suppose I am the sucker. I don’t care if the OP gets a 100% on her/his homework without doing the work. That is on her/his conscious. I answered the questions…what the OP does with the information is no longer my concern. Quite honestly, after reading the steps posted of how to solve the problems, I was confused.

So according to your logic I can be a student in your class, cheat on every test and ace the class and you would be ok with that because it would be on my conscious? Do you think you do students any favors by giving them the answers. It's not hard to deduce that the op is asking for the answers based on join date and similar posts. If they truly wanted help in finding the answer they probably would have posted some type of leg work showing he/she attempted to do the work on their own. And using your analogy about back pain for someone in the ER, yes if someone has been to ER 20 times in a month, has allergies to all NSAIDs, and states only Dilaudid 4mg works for them, than yes you can deduce they are in fact a drug seeker.

Would you want to be the patient sitting on the other end of a nurse that was given all the answers throughout school? Who wouldn't know what to do when you needed it most because they don't know the how to come up with an answer.

ParkerBC,MSN,RN, PhD, RN · Jul 20, 2011

"so according to your logic i can be a student in your class, cheat on every test and ace the class and you would be ok with that because it would be on my conscious?"

where did you dream of this response? nowhere in any of my responses did i allude to the fact that i support students cheating. let's exercise a little critical thinking skills here, okay? the op makes a post needing help with some problems. i think it is safe to assume the op is not sitting in class taking an exam. i would also venture to say the op doesn't have a take home test as the accrediting bodies and higher education institutions frown upon that practice. i think it is perfectly acceptable for a student to come to the website and ask for help. i also think it is acceptable for a member of the website to provide answers. the student is learning how to use his/her resource to his/her advantage; a skill that is often times not taught in higher education.

i really don't give a damn if my students receive answers from other classmates or by other means for their homework. that is why the homework is only worth 10% of my student's final grade. if the students do not put forth the effort in learning the material, it is reflected on their exam grades. there are multiple learning styles and teaching styles. if you have never had a class of 30 students with varying needs, then i don't expect you to understand.

"do you think you do students any favors by giving them the answers. it's not hard to deduce that the op is asking for the answers based on join date and similar posts. if they truly wanted help in finding the answer they probably would have posted some type of leg work showing he/she attempted to do the work on their own."

if i don't work the problems out and provide answers, how in the world would you expect students to learn? how do you think math or dosage calculations is taught? it is taught by working out example problems. how do you expect a student to provide any leg work if he/she is clueless of how to start?

"and using your analogy about back pain for someone in the er, yes if someone has been to er 20 times in a month, has allergies to all nsaids, and states only dilaudid 4mg works for them, than yes you can deduce they are in fact a drug seeker."

you labeled the op with limited information. that is the point i am making. you cannot, with complete certainty, say the op's intention was to get the answers to the problems. if a patient comes to the er 20 times because of their back, perhaps the md's are missing something. if a patient asks for dialudid 4mg, maybe they have a built up tolerance because no one is committed to find out what is really wrong with the patient. if a patient shows up that many times, either they have a back problem, mental problem, or an addiction. to simply jump to the latter option is premature.