Dopamine Calculations and Administration Guide

Hey everyone, it's Sarah with RegisteredNurseRN.com and in this video we're going to go over how to solve dopamine calculations. And after you watch this YouTube video, you can access the free quiz that will give you more practice over these calculations. So let's get started. First, let's do a quick pharmacology review over dopamine. This drug is a beta-adrenergic agonist, which means it acts as a vasopressor with positive inotropic effects. Now, what does this mean? Well, vasopressors, what they do is they perform vasoconstriction. They really press down that vessel, make it narrow. And whenever that happens, that will help increase blood pressure, increase systemic vascular resistance. increase our cardiac output. Dopamine can be used in some patients in certain types of shock where they're experiencing severe hypotension, their cardiac output is low, or their systemic vascular resistance is low. You throw on the dopamine and that can help increase those values. In addition, because of dopamine's positive inotropic effects, it increases the heart's contractility, which means it helps the heart pump stronger. Another thing that... dopamine does in low doses, about 0.5 to 3 mcg per minute, is that it can actually cause renal vasodilation. So the vessels that feed our kidneys will dilate, which will increase perfusion to the kidneys. This can help increase our urinary output. The reason it does this is the way that the dopamine affects those dopaminergic receptors in the kidneys. Now, whenever we start getting into high doses of dopamine, about 2 to 3 mcg per minute, 10 mics per kilogram per minute, it actually has the opposite effect. You'll have constriction of those vessels that feed the kidneys. So only in low doses do you have the dilation. Now dopamine is administered IV and it's best given through a central line. Now why is that? Why do we want to give it through a central line rather than the basic IV cannula route? Well dopamine is a major vasoconstrictor. So if extravasation occurs... where dopamine accidentally leaks into that surrounding tissue, it can lead to tissue ischemia, necrosis. So as a nurse, you've really got to watch that infusion site. And if this does occur, what medication can be given to help, in a sense, reverse those vasoconstrictive effects? You can give Phentolamine, which causes vasodilation. So remember that drug for your vasopressors. And the infusion rate is anywhere between two to three times the normal dosage. to 20 mics per kilogram per minute. This infusion rate really depends on the parameters set by the physician. As a nurse, you will be titrating this drug based on whatever the physician wants that patient in. And some other things you want to remember with this drug, the patient will need to be on continuous EKG monitoring, looking at that rhythm. Dopamine can significantly increase the heart rate. So looking at the heart rate, looking at their blood pressure. monitoring that constantly, their urinary output as well because the way that dopamine can influence the perfusion to the kidneys and of course watching that IV site. Now let's do some practice dopamine calculations. Our problem says a patient is ordered to start an IV dopamine drip at 10 mcg per minute. The patient weighs 55 kg. You have a bag of dopamine that reads 800 mg per 500 mL. what will you set the IV pump rate at? So to solve this problem, we need to know three things. First, the patient's weight, because dopamine is weight-based, and we're told the patient weighs 55 kilograms. Second, the dose, how much is ordered. And what's ordered is 10 micrograms per kilogram per minute. And then third, what is available to us? This bag of dopamine that we have, how much does it contain? Well, we're told we have a 500 milliliter bag that has 800 milligrams of dopamine. dopamine. Now what we're trying to get to is the milliliters per hour because this is what we're going to set our IV pump at so it can achieve this ordered dose based on this patient's weight and what the physician wants. So to solve these problems, I like to use dimensional analysis and if you're not familiar with how to set up dimensional analysis, I have a whole series you can access that will show you how to do that. And I will be rounding these answers at the end to the nearest tenth. But for your nursing school, always follow the rounding. rules. So what I like to do is I like to start out with the weight and this one's easy because normally you have to go to pounds to kilograms but we're already in kilograms so we'll start out right with that. So 55 kilograms is how much our patient weighs. Now what's ordered It says for every kilogram this patient weighs, they need 10 micrograms per minute of dopamine. Well, our patient weighs 55 kilograms. So, 1 kilogram is equal to 10 micrograms. per minute because that's what they want. So our kilograms cancels out and we're trying to get to milliliters per hour. Okay, so right now we're in micrograms because we're talking about 10 micrograms and our bag is in milligrams. So we're going to have to convert because we need to get there. So we know that 1,000 micrograms equals 1 milligram. 1,000 micrograms equals 1 milligram. That cancels out our micrograms. So now we're in milligrams. Now we can plug in our dose that's available. So we have a bag that has 800 milligrams of dopamine. and 500 mLs. Well, we're trying to get to milliliters per hour, but we're at milliliters per minute right now. That's what's left over. So we're going to go ahead and solve. So we're going to multiply everything at the top and everything at the bottom. So 55 times 10 times 1 times 500 is 275,000. And then 1 times 1 times 1,000 times 800 is 800,000. we're going to divide that out when we divide that we get 0.34375 milliliters per minute but we got to get to milliliters per hour so how are we going to do that well we're going to set this up over here we know that there's 60 minutes in one hour and with this for every minute we're going to give point 0.34375 mils. So one minute equal to 0.34375 milliliters. Minutes cancels out. We're now in milliliters per hour. So 60 times 0.34375 gives us 20.625. And when you multiply that at the bottom, of course that gives you... you one and you divide that out we're going to round to the nearest tenth will give us 20.6 milliliters per hour that's our answer our next problem says a patient is ordered to start an iv dopamine drip at five micrograms per kilogram per minute the patient weighs 180 pounds you have a bag of dopamine that reads 400 milligrams per 250 mls what will you set the iv pump at So to solve this problem, we need to know those three basic things that we discussed before. We need to know the weight, which is 180 pounds, the dose, which is 5 micrograms per kilogram per minute, and what's available to us. We have a 250 ml bag of dopamine that contains 400 milligrams. And we're trying to get to milliliters per hour because that's what we're going to set our pump at. So let's start out with our weight. And here we're going to have to convert from pounds to kilograms. So the patient weighs 180 pounds. pounds. And we know according to the metric table that there's 2.2 pounds in one kilogram. So 2.2 pounds in one kilogram. So our pounds cancels out. We're finally in kilograms. So now let's plug in our dose. The dose says for every kilogram that patient weighs, they need five micrograms per minute of dopamine. So one kilogram is going to be equal to five micrograms per minute. kilograms cancels out. Remember we're trying to get milliliters per hour. Now we need to do some converting because our bag is in milligrams and right now we're still in micrograms. So we know from the metric table that there's a thousand micrograms in one milligram. So micrograms cancels out and now we can plug in what we have available to us. And we have a bag. It contains four. 400 milligrams and 250 mls so we're going to go ahead and solve we're going to multiply everything at the top so 180 times 1 times 5 times 1 times 250 is 225 000 and then multiply everything at the bottom 1 times 2.2 times 1 times 1000 times 400 is 880 000 and then when we divide that out we will get 0.2556818 repeating so that is milliliters per minute but we need to get to milliliters per hour so we're going to do a little bit more dimensional analysis and we know that there are 60 minutes in one hour and we know with this what we've calculated for every minute they will be received receiving 0.2556818 repeating. So one minute is equal to that. And when we multiply that at the top, that at the bottom, what are we gonna get? We're gonna get 15.3409 repeating. And then we're gonna round to the nearest 10. and our answer will be 15.3 milliliters per hour. Okay so that wraps up how to solve IV dopamine drip calculations. Thank you so much for watching. Don't forget to take the free quiz and to subscribe to our channel for more videos.

Now, what does this mean? Well, vasopressors, what they do is they perform vasoconstriction. They really press down that vessel, make it narrow.

And whenever that happens, that will help increase blood pressure, increase systemic vascular resistance. increase our cardiac output. Dopamine can be used in some patients in certain types of shock where they're experiencing severe hypotension, their cardiac output is low, or their systemic vascular resistance is low.

You throw on the dopamine and that can help increase those values. In addition, because of dopamine's positive inotropic effects, it increases the heart's contractility, which means it helps the heart pump stronger. Another thing that... dopamine does in low doses, about 0.5 to 3 mcg per minute, is that it can actually cause renal vasodilation. So the vessels that feed our kidneys will dilate, which will increase perfusion to the kidneys.

This can help increase our urinary output. The reason it does this is the way that the dopamine affects those dopaminergic receptors in the kidneys. Now, whenever we start getting into high doses of dopamine, about 2 to 3 mcg per minute, 10 mics per kilogram per minute, it actually has the opposite effect. You'll have constriction of those vessels that feed the kidneys.

So only in low doses do you have the dilation. Now dopamine is administered IV and it's best given through a central line. Now why is that? Why do we want to give it through a central line rather than the basic IV cannula route?

Well dopamine is a major vasoconstrictor. So if extravasation occurs... where dopamine accidentally leaks into that surrounding tissue, it can lead to tissue ischemia, necrosis. So as a nurse, you've really got to watch that infusion site. And if this does occur, what medication can be given to help, in a sense, reverse those vasoconstrictive effects?

You can give Phentolamine, which causes vasodilation. So remember that drug for your vasopressors. And the infusion rate is anywhere between two to three times the normal dosage. to 20 mics per kilogram per minute. This infusion rate really depends on the parameters set by the physician.

As a nurse, you will be titrating this drug based on whatever the physician wants that patient in. And some other things you want to remember with this drug, the patient will need to be on continuous EKG monitoring, looking at that rhythm. Dopamine can significantly increase the heart rate. So looking at the heart rate, looking at their blood pressure. monitoring that constantly, their urinary output as well because the way that dopamine can influence the perfusion to the kidneys and of course watching that IV site.

Now let's do some practice dopamine calculations. Our problem says a patient is ordered to start an IV dopamine drip at 10 mcg per minute. The patient weighs 55 kg.

You have a bag of dopamine that reads 800 mg per 500 mL. what will you set the IV pump rate at? So to solve this problem, we need to know three things.

First, the patient's weight, because dopamine is weight-based, and we're told the patient weighs 55 kilograms. Second, the dose, how much is ordered. And what's ordered is 10 micrograms per kilogram per minute.

And then third, what is available to us? This bag of dopamine that we have, how much does it contain? Well, we're told we have a 500 milliliter bag that has 800 milligrams of dopamine. dopamine. Now what we're trying to get to is the milliliters per hour because this is what we're going to set our IV pump at so it can achieve this ordered dose based on this patient's weight and what the physician wants.

So to solve these problems, I like to use dimensional analysis and if you're not familiar with how to set up dimensional analysis, I have a whole series you can access that will show you how to do that. And I will be rounding these answers at the end to the nearest tenth. But for your nursing school, always follow the rounding.

rules. So what I like to do is I like to start out with the weight and this one's easy because normally you have to go to pounds to kilograms but we're already in kilograms so we'll start out right with that. So 55 kilograms is how much our patient weighs.

Now what's ordered It says for every kilogram this patient weighs, they need 10 micrograms per minute of dopamine. Well, our patient weighs 55 kilograms. So, 1 kilogram is equal to 10 micrograms.

per minute because that's what they want. So our kilograms cancels out and we're trying to get to milliliters per hour. Okay, so right now we're in micrograms because we're talking about 10 micrograms and our bag is in milligrams.

So we're going to have to convert because we need to get there. So we know that 1,000 micrograms equals 1 milligram. 1,000 micrograms equals 1 milligram. That cancels out our micrograms.

So now we're in milligrams. Now we can plug in our dose that's available. So we have a bag that has 800 milligrams of dopamine. and 500 mLs.

Well, we're trying to get to milliliters per hour, but we're at milliliters per minute right now. That's what's left over. So we're going to go ahead and solve. So we're going to multiply everything at the top and everything at the bottom. So 55 times 10 times 1 times 500 is 275,000.

And then 1 times 1 times 1,000 times 800 is 800,000. we're going to divide that out when we divide that we get 0.34375 milliliters per minute but we got to get to milliliters per hour so how are we going to do that well we're going to set this up over here we know that there's 60 minutes in one hour and with this for every minute we're going to give point 0.34375 mils. So one minute equal to 0.34375 milliliters.

Minutes cancels out. We're now in milliliters per hour. So 60 times 0.34375 gives us 20.625.

And when you multiply that at the bottom, of course that gives you... you one and you divide that out we're going to round to the nearest tenth will give us 20.6 milliliters per hour that's our answer our next problem says a patient is ordered to start an iv dopamine drip at five micrograms per kilogram per minute the patient weighs 180 pounds you have a bag of dopamine that reads 400 milligrams per 250 mls what will you set the iv pump at So to solve this problem, we need to know those three basic things that we discussed before. We need to know the weight, which is 180 pounds, the dose, which is 5 micrograms per kilogram per minute, and what's available to us.

We have a 250 ml bag of dopamine that contains 400 milligrams. And we're trying to get to milliliters per hour because that's what we're going to set our pump at. So let's start out with our weight.

And here we're going to have to convert from pounds to kilograms. So the patient weighs 180 pounds. pounds.

And we know according to the metric table that there's 2.2 pounds in one kilogram. So 2.2 pounds in one kilogram. So our pounds cancels out.

We're finally in kilograms. So now let's plug in our dose. The dose says for every kilogram that patient weighs, they need five micrograms per minute of dopamine.

So one kilogram is going to be equal to five micrograms per minute. kilograms cancels out. Remember we're trying to get milliliters per hour. Now we need to do some converting because our bag is in milligrams and right now we're still in micrograms. So we know from the metric table that there's a thousand micrograms in one milligram.

So micrograms cancels out and now we can plug in what we have available to us. And we have a bag. It contains four.

400 milligrams and 250 mls so we're going to go ahead and solve we're going to multiply everything at the top so 180 times 1 times 5 times 1 times 250 is 225 000 and then multiply everything at the bottom 1 times 2.2 times 1 times 1000 times 400 is 880 000 and then when we divide that out we will get 0.2556818 repeating so that is milliliters per minute but we need to get to milliliters per hour so we're going to do a little bit more dimensional analysis and we know that there are 60 minutes in one hour and we know with this what we've calculated for every minute they will be received receiving 0.2556818 repeating. So one minute is equal to that. And when we multiply that at the top, that at the bottom, what are we gonna get?

We're gonna get 15.3409 repeating. And then we're gonna round to the nearest 10. and our answer will be 15.3 milliliters per hour. Okay so that wraps up how to solve IV dopamine drip calculations.

Thank you so much for watching. Don't forget to take the free quiz and to subscribe to our channel for more videos.

Transcript for:Dopamine Calculations and Administration Guide

Transcript for:
Dopamine Calculations and Administration Guide