This is another video in my math for meds/dimensional analysis series. This one focused on weight based dosage calculations.
Hi everybody i am that nursing prof and welcome to my channel in today’s video we’re going to be focusing on weight-based calculations so let’s jump into our first practice one a nurse is preparing to administer medication b to an adult patient the prescription is one milligram per kilogram per dose every 12 hours the patient weighs 95 pounds so a petite adult
A little adult right so how many milligrams should the nurse administer per dose so we’re looking for milligrams so we’re gonna have milligrams here and if it’s going to be here it needs to be in our numerator so where do we see it in here up here so 1 milligram per kilogram per dose so if you were curious how do we write this in equation form this is what it
Looks like okay so the milligrams is in the numerator and the kilograms per dose is in your denominator what else do we need to put in here we need to put in a converting factor because we don’t have the patient’s weight in kilograms we only have it in pounds right so we’ll put 95 pounds up here over one and we need to convert pounds to kilograms so 2.2 pounds
Is one kilogram so we’ll cancel the kilograms out we’ll cancel the pounds out and then we’ll get milligrams overdose now if you want to put dose in your numerator here or in your denominator here excuse me you can you don’t technically have to it’s kind of just implied but if you want to write it like this that’s also correct so you’ll punch it in you’ll do your
Math and you’ll get 40 depending on whether or not the question wants you to round you’ll get 43.2 or you’ll just get 43. it’ll depend it’ll tell you in the question if they want you to round or not in this one we’re just going to say no it’s fine so we get 43.2 milligrams per dose let’s do another one okay let’s do another one a patient has a prescription for
Medication a one milligram per kilogram per dose the patient weighs 185 pounds how many milligrams should be given so we’re looking for milligrams so we’ll put milligrams in our answer we want to have milligrams in our numerator so where is that that’s up here so one milligram per kilogram per dose what else do we know we know the patient weighs 185 pounds and
Now we need to convert pounds and kilograms so one kilogram is 2.2 pounds so the kilograms will cancel the pounds will cancel this leaves us milligrams per dose so you can keep it like this or you can write milligrams per dose here punch it in your calculator do the math and you get 84.1 milligrams per dose now let’s do one with a child so a nurse is preparing to
Administer medication c 10 milligrams per kilogram per dose to a child who weighs 28 pounds the amount available is medication c 120 milligrams per 5 ml how many mls should the nurse administer and we’re not going to round on this one because it doesn’t say it anywhere so ml’s is what we want in our answer so ml’s has to be in our numerator somewhere where is it
In the problem it’s right here so 5 mls is 120 milligrams what else do we know we know that we want to give 10 milligrams per kilogram per dose so we can put that here 10 milligrams per kilogram per dose we also know the child’s weight which is 28 pounds so we’ll put 28 pounds over one and then we need a converting factor for our pounds to kilograms right so one
Kilogram is 2.2 pounds now we can start canceling things out so milligrams will cancel kilograms will cancel and our pounds will cancel that leaves us with ml’s per dose you punch it in do the math and you get 5.3 ml per dose this next one is a little bit different because up until this point we’ve been doing milligrams per kilograms per dose and the dose has been
Kind of implied at the end and this one it’s not because we’re doing milligrams per kilograms per day so let’s jump into it and see if we can figure it out we have the nurse she’s gonna administer medication m 15 milligrams per kilograms per day this is divided equally every 12 hours the patient weighs 198 pounds how many milligrams should the nurse administer with
Each dose so we want to know milligrams right so we’ll put milligrams here in our answer and where do we see it here in the problem to put it up here right there right so 15 milligrams per kilograms per day what else do we know we know the patient weighs 198 pounds and we know we need to convert pounds to kilograms so 198 pounds over one and then one kilogram
Is 2.2 pounds so the kilograms will cancel the pounds will cancel but this leaves us with milligrams per day right and that’s not what it’s asking it’s asking for milligrams per dose so when we do the math for milligrams per day i wrote it down because i don’t have it memorized as 13.50 okay and now we need to go one step further because this isn’t about the day
It’s about each dose how many doses are we going to give in this day two right because it’s every 12 hours and there’s 24 hours in a day so we’re going to divide this by 2 and that gets us 675 milligrams per dose so this is our answer okay this is helping us get to our answer but this is what the question is asking for it’s asking per dose not per day so that
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Transcribed from video
WEIGHT BASED DOSAGE CALCULATION (MG/KG/DOSE) By That nursing prof