Understanding and Solving ABG Problems

Hey everyone, it's Nurse Sarah with RegisteredNurseRN.com and in this video I'm going to be solving arterial blood gas problems using the ROAM method. So let's get started. The ROAM method is another type of method you can use to help you solve arterial blood gas problems. In the previous video we talked about the tic-tac-toe method, but today we're going to concentrate on ROAM. So ROAM is an acronym that stands for respiratory opposite, metabolic equal. And whenever you're using this method to help you solve arterial blood gases, I really recommend that you keep the R and the O together and the M and E together. Think of them going together because it'll help you understand how to use this method. So R and O it means respiratory opposite. Whenever we're talking about respiratory, we're talking about the PaCO2. So that lab value goes with this part of the acronym. And then ME is metabolic equal and where we're talking about about the metabolic system the lab value we're looking at is the bicarb the hco3 so that's going to go with this part of the acronym so now let's look at how we use these letters to get the answer to our abg problem so you want to memorize this little chart here and first off we have the r and the o which again is respiratory opposite and we're particularly looking at two values with this we're looking at the paco2 and the blood ph and we're looking for them to be opposite of each other. So we're paying attention to which way the arrow is pointing up or down. So one's going to be up and one's going to be down or vice versa. And if we have that presenting with our blood pH and that value, we have a respiratory problem. For instance, let's look at this. Okay. So we have a high PaCO2 and we have a low blood pH. That means we have respiratory acidosis because we know when our blood pH drops, it's acidic. And we know when we're Keeping too much carbon dioxide, we're going to have acidosis because CO2 helps create carbonic acid, which influences our hydrogen ion concentration, which makes us more acidic. Now, whenever we have a low PaCO2 and a high pH, we're going to have respiratory alkalosis. So see how they're opposite. Those values are in opposite directions. Now let's look at our M and our E. So this is metabolic equal and with metabolic we're talking about the bicarb the hco3. So for this part of the method we're talking about the bicarb and the blood pH. So they have to be equal, meaning they're going in the same direction. Either they're both high or they're both low. And if that's happening, we have a metabolic problem. So for instance, if we have a low bicarb and a low blood pH, we have metabolic acidosis. Or if we have a high bicarb and a high blood pH, we have metabolic alkalosis. Now to help you interpret these values if they're high, low, or normal, you have to have the normal ranges memorized and what each range means. So let's quickly go over that. For blood pH, a normal blood pH is 7.35 to 7.45. This is the measurement of hydrogen ion concentration in our blood. So a value of less than 7.35 would be considered acidic and we would put a down arrow because it's down. If the blood pH is greater than 7.45, that is basic alkaline, it is elevated. So we would have an up arrow. Now for PaCO2, this is the amount of carbon dioxide in the arterial blood. A normal level is about 35 to 45 millimeters of mercury. With respiratory, it's opposite, hence the part of our mnemonic or acronym that says respiratory opposites. So whenever we're talking about 35 to 45, it's like flipped what's going to be a base and what's going to be... acid for instance if it's greater than 45 that's considered an acid so it's elevated because we have a lot of carbon dioxide in our body so we would have an up arrow now if it's less than 35 it's a base and we have low co2 so it's a down arrow Don't let that confuse you. Commit that to memory. Make sure you grasp that because that'll help you whenever you're using this method to solve. Then we're going to look over at the bicarb, the HCO3. A normal level of this is 22 to 26 milliequivalents. So this is going to follow the same thing like how our blood pH did. So a level less than 22 is considered acidic. It's low. So we put a down arrow. And a level greater than 26 is considered basic alkaline. and we would have an up arrow. Now let me quiz you on this. Let's see how well you grasp this. Okay, we have a blood pH of 7.23. What is that? It's acidic, so we would put a down arrow. Next, we have a PaCO2 of 13. 32. Is this acidic? Is it normal or a base? It is a base and because it's 32 it's low so we would have a down arrow. Then we have a bicarb HCO3 of 18. What's this? This is an acid and it's low so we would have a down arrow. And then lastly we have a PaCO2 of 51. What would this be? It is acidic and because it's high we would put an up arrow. Now let's solve some ABG problems using this method. So these problems I'm actually going to solve come from a book I just released on ABG interpretation, which is a workbook that has a lot of cheat sheet style notes and extra practice problems so you can get proficient at solving these problems. Now let's look at our first problem. So it says we have a blood pH of 7.27, a PaCO2 of 42, and a bicarb HCO3 of 17. Very first thing what we want to do is we want to set up this method. So we're going to put R-O-M-E vertically and then just over here to the side we're going to put our pH. Now what we want to do is we want to analyze that blood pH. Is it acidic, normal, or basic? So our blood pH is 7.27. That is low so we're going to put a down arrow and it's acidic. So in parentheses we're going to put acid just so we can keep it straight. Then we're going to look at the PaCO2. It's 42. A normal is 35 to 45. So this falls within that normal range. So next to R because that is representing our PaCO2, we're just going to put normal. Then we're going to go look at that bicarb HCO3 at 17. A normal is 22 to 26. So this is on the low side. We're going to put a down arrow next to the M because that is the metabolic part. And we're going to put in parentheses acid. Just to let us know it's an acid. Now we're going to look, do we have what we talked about earlier that we need to memorize that chart? Do we have respiratory opposite or metabolic equal? We have metabolic equal because notice our bicarb is low and our blood pH is low. They're equal. They're same. Respiratory system was normal. So we don't even have that. So we have metabolic equal. So we're going to put an X up here at the O and a check mark at the E. So based on all that, we have metabolic acidosis. Now we need to look and see if we have some type of compensation going on. So first off, we can look for full compensation and do we have full compensation? The answer is no because our blood pH is abnormal. Our blood pH would have to be normal in order for us to have full compensation. And here in a moment we'll be solving full compensation problems so you can get familiar with that. Now we need to move on. Do we have partial compensation or uncompensation? And the answer is it's uncompensated. And the reason we know is because we have a metabolic problem so we're gonna look over at that respiratory system seeing if it's trying to help balance it out what's going on because we have acidosis did the respiratory system try to make itself more alkaline by making that paco2 less than 35 it did not so it's not trying to partially compensate so here we have uncompensation. Now this problem says we have a blood pH of 7.55, a PaCO2 of 32, and an HCO3 of 18. So the first thing what we want to do is we want to write out our little acronym R-O-M-E vertically and then put a pH over here to the right. So first let's analyze our pH at 7.55. A normal is 7.35 to 7.45. So this is high. So next to pH, we're going to put an up arrow and we're going to put its basic, its alkaline. Then let's look at PaCO2. It is 32. So over here on the R and the O part with the R, it is low because a normal is 35 to 45. And this is basic. So we're going to put base in parentheses. Then we're going to look at the bicarb, the HCO3. Normal is 22 to 26. This is on the low side. So down here at the M, we're going to put... down arrow and put in parentheses that it's an acid. So let's think back to that chart we needed to memorize. Do we have respiratory opposite or metabolic equal? Let's look at that blood pH. It is elevated. Our respiratory PaCO2 is decreased. So we have respiratory opposite. So we definitely have a respiratory disorder. We don't have metabolic. equal because notice our HCO3 is low and our pH is high. So they're opposite of each other. So we have respiratory opposite. And what we have is respiratory alkalosis. So we want to determine if we have compensation or not. So first we can look to see if we have full compensation and we don't because our blood pH is abnormal. It is 7.55 normal, 7.35, 7.45. So we can rule that out, but we need to determine do we have uncompensation or partial compensation? So we have a respiratory problem Let's look at that metabolic system the bicarb to see if it's abnormal or normal because I can help tell us where we stand So our bicarb HCO3 is 18. It's abnormal. It's on the acidic side. So we have alkalosis going on respiratory. Therefore the metabolic system tried to make things a little bit more acidic so we can hopefully decrease that pH. So it's trying to compensate. So it would be respiratory alkalosis partial compensation. Now if that bicarb was normal within that 22 to 26 range it would be uncompensated. Our next problem says that we have a blood pH of 7.44, a PaCO2 of 49, and a bicarb of 33. So the first thing we're going to do is ride out Rome, R-O-M-E vertically and then put our blood pH over here to the right. So we want to first analyze that blood pH. It's 7.44. A normal is 7.35 to 7.45. So our blood pH is normal. So next to pH we're going to write normal. Now let's further analyze this blood pH. pH because this should be tipping us off that we have full compensation but to help us further solve the problem we've got to analyze this blood pH just a little bit more so an absolute normal blood pH right there in the middle is seven point four zero Anything less than 7.40 is considered to be normal acidic blood pH, so it's on the acid side, so it would be low. And anything greater than 7.40 is elevated on the normal side. alkalotic so here ours is 7.44 so we would consider this normal but it's basic it's alkaline so it's elevated normal so we're going to put a little up arrow right there and just put in parentheses base, because it's on the base side. Then we're going to look at the PaCO2. It is 49, and normal is 35 to 45, so it's on the high side, so we're going to put an up arrow, and we're going to put it's on the acid. And then we're going to look down at the bicarb, the HCO3, it's 33, and normal is 22 to 26. So this is elevated, so where M is, we're going to put metabolic, we're going to put an up arrow, and then we're going to. put in parentheses it's a base because that's what that value is looking at our chart that we memorized earlier we are looking for respiratory opposite or metabolic equal and based on that blood ph it is equal with metabolic they're both going in the same direction so we have metabolic equal we do not have a respiratory opposite because notice that those arrows are going in the same direction so our answer is metabolic alkalosis and we know that we have full compensation because our blood ph is normal. Okay, so that wraps up this video on using the Roe method to solve ABG problems. If you'd like more problems, you can access the free quiz in the description below.

And whenever you're using this method to help you solve arterial blood gases, I really recommend that you keep the R and the O together and the M and E together. Think of them going together because it'll help you understand how to use this method. So R and O it means respiratory opposite.

Whenever we're talking about respiratory, we're talking about the PaCO2. So that lab value goes with this part of the acronym. And then ME is metabolic equal and where we're talking about about the metabolic system the lab value we're looking at is the bicarb the hco3 so that's going to go with this part of the acronym so now let's look at how we use these letters to get the answer to our abg problem so you want to memorize this little chart here and first off we have the r and the o which again is respiratory opposite and we're particularly looking at two values with this we're looking at the paco2 and the blood ph and we're looking for them to be opposite of each other.

So we're paying attention to which way the arrow is pointing up or down. So one's going to be up and one's going to be down or vice versa. And if we have that presenting with our blood pH and that value, we have a respiratory problem.

For instance, let's look at this. Okay. So we have a high PaCO2 and we have a low blood pH. That means we have respiratory acidosis because we know when our blood pH drops, it's acidic.

And we know when we're Keeping too much carbon dioxide, we're going to have acidosis because CO2 helps create carbonic acid, which influences our hydrogen ion concentration, which makes us more acidic. Now, whenever we have a low PaCO2 and a high pH, we're going to have respiratory alkalosis. So see how they're opposite. Those values are in opposite directions. Now let's look at our M and our E.

So this is metabolic equal and with metabolic we're talking about the bicarb the hco3. So for this part of the method we're talking about the bicarb and the blood pH. So they have to be equal, meaning they're going in the same direction. Either they're both high or they're both low.

And if that's happening, we have a metabolic problem. So for instance, if we have a low bicarb and a low blood pH, we have metabolic acidosis. Or if we have a high bicarb and a high blood pH, we have metabolic alkalosis.

Now to help you interpret these values if they're high, low, or normal, you have to have the normal ranges memorized and what each range means. So let's quickly go over that. For blood pH, a normal blood pH is 7.35 to 7.45. This is the measurement of hydrogen ion concentration in our blood. So a value of less than 7.35 would be considered acidic and we would put a down arrow because it's down.

If the blood pH is greater than 7.45, that is basic alkaline, it is elevated. So we would have an up arrow. Now for PaCO2, this is the amount of carbon dioxide in the arterial blood.

A normal level is about 35 to 45 millimeters of mercury. With respiratory, it's opposite, hence the part of our mnemonic or acronym that says respiratory opposites. So whenever we're talking about 35 to 45, it's like flipped what's going to be a base and what's going to be...

acid for instance if it's greater than 45 that's considered an acid so it's elevated because we have a lot of carbon dioxide in our body so we would have an up arrow now if it's less than 35 it's a base and we have low co2 so it's a down arrow Don't let that confuse you. Commit that to memory. Make sure you grasp that because that'll help you whenever you're using this method to solve.

Then we're going to look over at the bicarb, the HCO3. A normal level of this is 22 to 26 milliequivalents. So this is going to follow the same thing like how our blood pH did. So a level less than 22 is considered acidic.

It's low. So we put a down arrow. And a level greater than 26 is considered basic alkaline. and we would have an up arrow. Now let me quiz you on this.

Let's see how well you grasp this. Okay, we have a blood pH of 7.23. What is that?

It's acidic, so we would put a down arrow. Next, we have a PaCO2 of 13. 32. Is this acidic? Is it normal or a base? It is a base and because it's 32 it's low so we would have a down arrow.

Then we have a bicarb HCO3 of 18. What's this? This is an acid and it's low so we would have a down arrow. And then lastly we have a PaCO2 of 51. What would this be?

It is acidic and because it's high we would put an up arrow. Now let's solve some ABG problems using this method. So these problems I'm actually going to solve come from a book I just released on ABG interpretation, which is a workbook that has a lot of cheat sheet style notes and extra practice problems so you can get proficient at solving these problems. Now let's look at our first problem.

So it says we have a blood pH of 7.27, a PaCO2 of 42, and a bicarb HCO3 of 17. Very first thing what we want to do is we want to set up this method. So we're going to put R-O-M-E vertically and then just over here to the side we're going to put our pH. Now what we want to do is we want to analyze that blood pH. Is it acidic, normal, or basic? So our blood pH is 7.27.

That is low so we're going to put a down arrow and it's acidic. So in parentheses we're going to put acid just so we can keep it straight. Then we're going to look at the PaCO2. It's 42. A normal is 35 to 45. So this falls within that normal range.

So next to R because that is representing our PaCO2, we're just going to put normal. Then we're going to go look at that bicarb HCO3 at 17. A normal is 22 to 26. So this is on the low side. We're going to put a down arrow next to the M because that is the metabolic part.

And we're going to put in parentheses acid. Just to let us know it's an acid. Now we're going to look, do we have what we talked about earlier that we need to memorize that chart? Do we have respiratory opposite or metabolic equal?

We have metabolic equal because notice our bicarb is low and our blood pH is low. They're equal. They're same.

Respiratory system was normal. So we don't even have that. So we have metabolic equal. So we're going to put an X up here at the O and a check mark at the E. So based on all that, we have metabolic acidosis.

Now we need to look and see if we have some type of compensation going on. So first off, we can look for full compensation and do we have full compensation? The answer is no because our blood pH is abnormal. Our blood pH would have to be normal in order for us to have full compensation. And here in a moment we'll be solving full compensation problems so you can get familiar with that.

Now we need to move on. Do we have partial compensation or uncompensation? And the answer is it's uncompensated. And the reason we know is because we have a metabolic problem so we're gonna look over at that respiratory system seeing if it's trying to help balance it out what's going on because we have acidosis did the respiratory system try to make itself more alkaline by making that paco2 less than 35 it did not so it's not trying to partially compensate so here we have uncompensation.

Now this problem says we have a blood pH of 7.55, a PaCO2 of 32, and an HCO3 of 18. So the first thing what we want to do is we want to write out our little acronym R-O-M-E vertically and then put a pH over here to the right. So first let's analyze our pH at 7.55. A normal is 7.35 to 7.45.

So this is high. So next to pH, we're going to put an up arrow and we're going to put its basic, its alkaline. Then let's look at PaCO2.

It is 32. So over here on the R and the O part with the R, it is low because a normal is 35 to 45. And this is basic. So we're going to put base in parentheses. Then we're going to look at the bicarb, the HCO3.

Normal is 22 to 26. This is on the low side. So down here at the M, we're going to put... down arrow and put in parentheses that it's an acid. So let's think back to that chart we needed to memorize.

Do we have respiratory opposite or metabolic equal? Let's look at that blood pH. It is elevated. Our respiratory PaCO2 is decreased. So we have respiratory opposite. So we definitely have a respiratory disorder.

We don't have metabolic. equal because notice our HCO3 is low and our pH is high. So they're opposite of each other.

So we have respiratory opposite. And what we have is respiratory alkalosis. So we want to determine if we have compensation or not. So first we can look to see if we have full compensation and we don't because our blood pH is abnormal.

It is 7.55 normal, 7.35, 7.45. So we can rule that out, but we need to determine do we have uncompensation or partial compensation? So we have a respiratory problem Let's look at that metabolic system the bicarb to see if it's abnormal or normal because I can help tell us where we stand So our bicarb HCO3 is 18. It's abnormal.

It's on the acidic side. So we have alkalosis going on respiratory. Therefore the metabolic system tried to make things a little bit more acidic so we can hopefully decrease that pH. So it's trying to compensate. So it would be respiratory alkalosis partial compensation.

Now if that bicarb was normal within that 22 to 26 range it would be uncompensated. Our next problem says that we have a blood pH of 7.44, a PaCO2 of 49, and a bicarb of 33. So the first thing we're going to do is ride out Rome, R-O-M-E vertically and then put our blood pH over here to the right. So we want to first analyze that blood pH. It's 7.44.

A normal is 7.35 to 7.45. So our blood pH is normal. So next to pH we're going to write normal. Now let's further analyze this blood pH. pH because this should be tipping us off that we have full compensation but to help us further solve the problem we've got to analyze this blood pH just a little bit more so an absolute normal blood pH right there in the middle is seven point four zero Anything less than 7.40 is considered to be normal acidic blood pH, so it's on the acid side, so it would be low.

And anything greater than 7.40 is elevated on the normal side. alkalotic so here ours is 7.44 so we would consider this normal but it's basic it's alkaline so it's elevated normal so we're going to put a little up arrow right there and just put in parentheses base, because it's on the base side. Then we're going to look at the PaCO2. It is 49, and normal is 35 to 45, so it's on the high side, so we're going to put an up arrow, and we're going to put it's on the acid. And then we're going to look down at the bicarb, the HCO3, it's 33, and normal is 22 to 26. So this is elevated, so where M is, we're going to put metabolic, we're going to put an up arrow, and then we're going to.

put in parentheses it's a base because that's what that value is looking at our chart that we memorized earlier we are looking for respiratory opposite or metabolic equal and based on that blood ph it is equal with metabolic they're both going in the same direction so we have metabolic equal we do not have a respiratory opposite because notice that those arrows are going in the same direction so our answer is metabolic alkalosis and we know that we have full compensation because our blood ph is normal. Okay, so that wraps up this video on using the Roe method to solve ABG problems. If you'd like more problems, you can access the free quiz in the description below.

Transcript for:Understanding and Solving ABG Problems

Transcript for:
Understanding and Solving ABG Problems