Okay, so now you know step 1,2, 3 and 4.
So in step 1,2 and 3 - we figured out where
we are, step 4 - we figured out whose fault it is.
Now give me a little picture there of an evil guy so we
think of him as the villain, that means whose fault it is.
Steps 5 and 6 will look at
how the body's responding
so we need the body to respond in a way that's
helpful, a way to compensate for that imbalance.
That's why he has a little superhero cape on and a
big letter on his chest, right? so there's our hero.
They were looking to see
if the body has responded
in a way that's beneficial or
helpful to get that pH back to normal.
We know the kidneys control the
bicarb, the lungs control the CO2.
So if we're having a respiratory
issue we look to the kidneys to help us.
If we're having a metabolic issue,
we look to the lungs to help you.
Okay, don't rush there without concept.
Right, if I'm in or respiratory acidosis,
that means my pH is too acidic, right?
So I'm gonna look to the kidneys, the opposite system to
see if they're working in a way that actually helps me.
Well if I'm acidic I
need more or less bicarb?
Right, I need more bicarb.
So if those kidneys are working in a way that helps
me, that bicarb level needs to be greater than normal.
So it needs to be greater than 26, that way
I will know that the kidneys are trying to help.
Okay, because remember you either
have a villain who cause the imbalance
or we're looking at the opposite system to see if
it's responding in a way that's actually helpful
in getting that pH back
to normal or homeostasis.
Remember if the lungs cause the problem, we look at the
metabolic or the kidney value to see if it's helping us
in a way that will move
that pH in the right direction.
If the kidneys are the problem, we look at
the lungs to see if they're reacting in a way
that helps us get us back to a normal pH.
So you do steps 1 through 4 on your own, pause the
video, we'll be back to talk about the answers.
Okay, welcome back.
Let's see if your labels
match ours on the screen.
pH of 7.25 is lower than the normal
pH of 7.35 so we labelled it acidotic.
Now CO2 of 55 is more than normal, right?
because the normal CO2 level is 35 to 45
so we label that acidotic because we
have excess CO2 in the blood or extra acid.
Now a bicarb of 22, bingo! that is right in the
line, right? It's 22-26 so we're still within normal.
So we label the pH acidotic,
we label the CO2 acidotic.
Because step 4, you do the pH matchup, we know
its CO2 is the problem and lungs control the CO2
so this patient is in respiratory acidosis.
The pH told us where we are - acidosis,
whose fault it is is the lungs because
the lungs control the CO2 levels.
So we're in respiratory acidosis, cool.
Now we need to look at, we
know that it's the lungs' fault
that's why our villain has a set of
lungs on his chest to remind you:
respiratory acidosis means the lungs are
the bad guys, they're the ones that got us there.
So now we're seeing if the body
is responding or compensating.
That's what's compensating
means, hey the body's out of balance
we're looking at the opposite
system, see if it's compensating.
We will see if we have a hero
because we know who the villain is,
now we're gonna look at the opposite system
to see if it's responding in a way that helps.
Now before we go forward, I want
you to take a good educated guess.
If we're in respiratory acidosis, we
know that it's the lungs' fault, right?
and we're gonna look at the
opposite system to see if it's helping.
Well the opposite system
is the metabolic system.
So what type of change do we
need to see from the metabolic system
to help us move from respiratory
acidosis back to a normal pH.
Do I need more bicarb
or do I need less bicarb?
You make your guess, pause the video but
write it down, you gotta commit to an answer.
So the question is, if the body is really compensating or
responding in a way that's helpful to respiratory acidosis,
is the bicarb level higher
or lower than normal?
Okay, got your answer written down?
Hang on to that, we're gonna walk through some
different steps, let's see if you got it right.
So when we're talking about compensation,
we already did steps 1, 2, 3 and 4, right?
We know that we're in respiratory acidosis.
That means the lungs are the ones that got us here,
that's why the villain has a set of lungs on his chest.
That's got there because we have an
elevated CO2, we have extra acid in our blood.
That's what made the respiratory acidosis.
We can back that up because the
CO2 level's 55, we know that's too high.
Now, how can we ge tback to normal,
we look at the opposite system, right?
That's the kidneys, now
what do the kidneys control?
Sweet! Bicarb, that's
what the kidneys control.
So we asked what would the kidneys need to do to
help us move an acidotic pH closer to normal?
Would we need more bicarb
which is basic, or less bicarb?
Well hopefully your answer said,
Right - more bicarb.
So in order to move a pH
that's too acidotic back to normal,
we need extra base or move towards alkalosis in order
to become normal, so we need a higher level of bicarb
So you're looking at that opposite system and seeing if the
values are outside of the normal range in a way that's helpful.
So in respiratory acidosis, I'd be looking for a
bicarb that is greater than normal or greater than 26
Okay, I promised that will make more
sense as we keep trying some more examples
If it's not, if that bicarb had not been outside of
normal in a way that's helpful, then it's not compensation.
But if it is outside of normal, if it's
greater than 26 but the pH is still not normal,
we call that partial compensation - it's like, hey
you're getting there but you're not quite there.
The reason it's partial compensation is
because the pH is not back within normal range
The pH is still acidotic but we see that the
kidneys have been able to respond in a way
that's outside of their
normal values and it's helpful.
That's partial compensation.
so when the lab values of the opposite system are within
normal range, it is on compensated respiratory acidosis
or whatever one of the four is.
So the lab values of the opposite system if they're not
outside of the normal range in a way that's helpful,
we consider it to be uncompensated.
Look at this example.
I want you to decide if you
think it's compensated or not.
We're in respiratory acidosis, you look at the
opposite system - the bicarb is 22, which is normal.
Is this compensated?
No, it's uncompensated.
The bicarb would have needed to be
greater than 26 in order for this to compensated.
So this is uncompensated
Now before we go on pause and make
sure, pretend you are teaching someone else,
give your rationale for why this lab value
is uncompensated respiratory acidosis.
I want you to talk through those
answers before we go forward
Okay, even pretending that you're teaching someone is a great
way to check your level of understanding of the concepts.
If there's something you're not clear on, stop
right here, go back and review those steps again,
then make sure that's
clear in your own mind.
Because that 5th step is to
look at the opposite system.
So if I'm saying the lungs, the
opposite system is the kidneys.
If I'm saying metabolic, the
opposite system are the lungs.
Now remember the lungs have the
faster and bigger impact than the kidneys.
The lungs can respond in change of respiratory rate
and volume and you'll see a bigger change in your CO2
than when the kidneys try
to deal with the bicarb level.
They're trying, it just takes a lot
longer for you to see a big impact on that.
So the opposite system is the one
where the responder compensate.
In respiratory acidosis we want
the kidneys to increase the bicarb
Acidosis means a more acidic, bicarb
is a base - that's why I need more of it.
if I'm in metabolic acidosis, the
opposite system would be the lungs.
So I'm gonna need the lungs to
respond in a way that has less CO2.
So the only things the lungs
can do, is breathe faster.
Now, here's one really cool
example, so hang with me.
Have you ever heard of
diabetic ketoacidosis ?
Yeah, that's what happens when a type I diabetic,
when their blood sugar just goes crazy high.
Diabetic ketoacidosis is a
form of metabolic acidosis.
Now there's a certain sign that goes along
with DKA - we call it the Kussmaul's respirations.
They breathe like this.
and this gets really weird,
Now you know why.
That's one symptom you have to memorize because
diabetic ketoacidosis is a form of metabolic acidosis
that means I'm in acidosis cause
it's the metabolic system's fault,
but my blood sugar is way high, so I
look to the lungs to see if they're helping.
Kussmaul respirations are the
body's attempt to blow off CO2
because the body recognises the pH is often DKA
and it's trying to get you back to homeostasis.
The only the lungs can help, is to try
and get rid of as much acid as possible
That's why they blow off CO2
and you have Kusmmaul's repirations.
See that's the cool part, once you do
the work of understanding lab values,
it's gonna open up a whole new world for you
and looking at what's going on to your patients
and helping them be safe.
Now here's our next example.
I want you to do this again on your own, so pause the
video, we'll come back and talk through it after you're done
Alrght, does this match your labels?
The pH was acidotic, the CO2 was alkalotic, the
bicarb was acidosis, so you did steps 1 through 5,
the bicarb and the pH match,
so this is metabolic acidosis.
Remember we talked through that other example that
DKA is just one example of a metabolic acidosis.
So we know where we are - we're acidosis.
We know whose fault it is that we got
there - it's metabolic system or the kidneys.
Now we're gonna look at the other systems,
see if it's responding in a way that's helpful.
Okay, so I'm in acidosis, I need less
acid, my CO2 is 32 that's less than normal.
That means I am in partially compensated metabolic acidosis
because the lungs are responding in a way that's helpful.
The CO2 level is outside of the normal range
and it's lower than normal -that's what we wanted.
so this person is in partially
compensated metabolic acidosis.
Good deal, now try the
steps again with this example.
Do yours match ours?
pH is acidotic, CO2 is acidotic, bicarb is alkalotic so when
you did the pH matchup, we're clearly in respiratory acidosis.
When you do step 5, you
look at the opposite system.
Normal is 22 to 26 (mmol/L), this is
34 so that means I have extra bicarb.
If I'm in respiratory acidosis will extra
bicarb help move my pH in the right direction?
Yeah, it sure will.
my pH is still off so I'm in partially
compensated respiratory acidosis.