MedMath questions

bigbaldguy

Former medic seven years 911 service in houston
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Anybody know of any good online resources for Med math. Boluses, single doses, infusions ect. I need some practice questions with answers and I've done all the ones in my work book. I've found some questions online but they generally don't have the answers with them so not terribly useful to me.
 
If you do not know already, can I recommend you learn dimensional analysis. It is a far easier and less error prone way to doing dose calculations. I first learned about this method in chemistry class, and have found it useful for many types of math problems. Check out this link. The link also has some quizzes.

http://www.alysion.org/dimensional/analysis.htm
 
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The time invested in learning dimensional analysis, well pays off. Plus you can usually get away with not having to memorize formulas. Lots of youtube videos available.
 
Thanks guys. No I do not know anything about the dimensional analysis thing. I'm embarrassed to say my math skills are generally non existent. I'll check it out though thanks.
 
also remember Desired dose / Dose available x quantity. You can solve a lot of questions with that formula. For instance you want to give 10mg Drug X and it is available in a vial that is 30 mg / 2 mL so you do 10/30x2 = .666 or .67 ml.
 
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Yet another reason why paramedicine should include an associates or BA level education. A requirement such as Gen-Chem would lay a basis for dimensional analysis.
 
Yet another reason why paramedicine should include an associates or BA level education. A requirement such as Gen-Chem would lay a basis for dimensional analysis.

Or at least have instructors capable of teaching dimensional analysis.

I was teaching med calcs (with DA) to a paramedic class for the first time about 8 months ago, and the lead instructor (no longer the lead instructor) pretty much balked and said "No one is going to be able to do that at 3 in the morning" and cut me off.

Needless to say, I am now in the lead instructor cadre, and the students learn DA, plain and simple. I don't expect them to whip it out for every 3 AM call they go on, but the basic concept of being able to calculate through multiple unit conversions is invaluable. The students seem to agree.

One of the things I like best about DA is that if you set up your units correctly, you should be able to cancel all the way through your equation and see if you have a reasonable answer before you even touch any mathematics.

Another thing I always tell students when doing med math is before you even do any math, look at the concentration of the medication and determine what is a reasonable volume for administration. For example, if you have a med that comes packaged 10 mg/ml in a 1 ml vial and your final answer says you need to administer 50 ml of volume, there is something definitely wrong. That answer means you would need 50 vials of that medication!

With a few exceptions, most manufacturers package medication so that a typical dose can be administered without having to open multiple packages.

If you would like, feel free to PM me. We can skype or chat sometime and I will run you through DA until you're blue in the face...
 
Thanks all. I agree that a few college level math courses would definitely help. I'm more of a "bag of pennies" kind of math guy. To be fair our instructor did try to explain the general concept of DA to us but I had no idea that's what it was at the time as I was still reeling from the first part of the lecture.
 
Thanks all. I agree that a few college level math courses would definitely help. I'm more of a "bag of pennies" kind of math guy. To be fair our instructor did try to explain the general concept of DA to us but I had no idea that's what it was at the time as I was still reeling from the first part of the lecture.

Wan't taking a shot at you for not being a math wizard! Just an idea for the future of medics. When i was in chem I found a great youtube tutorial..i'll try and find it for you.
 
Wan't taking a shot at you for not being a math wizard! Just an idea for the future of medics. When i was in chem I found a great youtube tutorial..i'll try and find it for you.

No worries I didn't take it that way but you are right I think having at least a basic understanding of math would be a huge boon. I was always a horrible math student and literally had trouble with long division so now I'm having to learn all the little tricks to doing it. I wish I had known some of this stuff back in the day I might have had fewer near panic attacks come test time.
 
The nice thing about DA is all you need is multiply and divide. That's it. :)
 
Hopefully your program doesn't make you do Dopamine calculations the long way. They prohibited the easy way being used in our class. :(
 
We do have to show our work but I don't think they mind us using the 3AM method as they call it. I actually find it easier to do it the long way my problem is that when I get to the end and have to divide 1700 by 64000 my head explodes.
 
Try the 3 AM NICU to NICU transfer where the baby is maxed out on dobutamine and epi, and the doc asks you to get ready to start norepi...and you still haven't switched everything over to your pumps...and the patient is volume restricted so all of your concentrations are doubled and your volume is halfed...and your final calculated volume is like 6 mL per hour or something crazy small...FML

One of the best pictures ever taken was of me and the nurse I was with hunched over a calculator with 4 30 cc syringes each with a different pressors plus a bag of TPN trying to get this baby squared away, heads lying on our palms...looking like we were taking a calculus test. I will have to see if I can find it for you...

If you ever get into Critical Care or Flight Medicine, you will never get caught without a calculator. Why do you think those flight suits have so many dang pockets...
 
They honestly don't allow calculators. Madness I tell ya, madness.
 
We do have to show our work but I don't think they mind us using the 3AM method as they call it. I actually find it easier to do it the long way my problem is that when I get to the end and have to divide 1700 by 64000 my head explodes.

Cancel the zeros!
 
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