In this video, we're going to talk about metabolic alkalosis and what lab values you would see
with uncompensated metabolic alkalosis, partially-compensated metabolic alkalosis, and fully compensated
metabolic alkalosis.
And we'll also cover the causes of this disorder, what symptoms you would see with metabolic
alkalosis, and what treatment options exist.
Okay.
So when we see a pH over 7.45, that means we have alkalosis, and we have to figure out
who's to blame.
If we look at PaCO2, if that's within normal range - so between 35 and 45 - then we know
the respiratory system isn't to blame.
And if we look at HCO3, or bicarbonate, which represents the metabolic system, if it is
over 26, then that is basic.
And then we know that we are dealing with metabolic alkalosis.
So in this case, we have uncompensated metabolic alkalosis.
We have alkalosis that is caused by the metabolic system.
And the respiratory system is chilling out and not doing anything to try to fix the situation.
Alright.
On this next row, again if pH is over 7.45, that means we have alkalosis.
If we look at the PaCO2, and it's over 45, then that is acidic.
So we know that the respiratory system is not causing the alkalosis It looks like it's
trying to compensate, though.
Right?
And then, if we go over here to bicarb, or HCO3, if it is over 26, then we know for sure
that we have metabolic alkalosis that the respiratory system is trying to compensate
for.
It's becoming acidic to try to compensate for this basic, or alkalosis.
So in this case, we have partially compensated metabolic alkalosis.
So we've got alkalosis caused by the metabolic system, and the respiratory system is trying
to fix the situation, but they haven't fixed it completely because our pH is still out
of range.
Okay.
Down here, if we have a pH that is within the normal range - so it is between 7.35 and
7.45, but it is on the high side of things - like if it's 7.44 or 7.45, then we may suspect
that there was some alkalosis that was being compensated.
So let's go over here to PaCO2, which is the respiratory system.
And we see that it's acidic.
It is over 45.
So that's definitely not anything that would be causing alkalosis.
But if we go over here to HCO3, we see that it's over 26, which means it is to blame for
the alkalosis.
But luckily for the metabolic system, the respiratory system came in and saved the day
and compensated, right?
It got so acidic that it was able to compensate for this alkalosis and get this pH into a
normal range.
So in this case, we have fully compensated metabolic alkalosis.
The metabolic system is to blame for the alkalosis; respiratory system has fixed the situation.
Alright, now let's talk about some of the common causes of metabolic alkalosis.
So one really common cause that I've definitely seen a lot in the hospital is an antacid overdose.
So if a patient is just popping those TUMS over and over, they can really throw their
acid-base balance out of whack, so they could definitely end up with metabolic alkalosis
if they take too many antacids.
Also, loss of body acids is a key cause of metabolic alkalosis.
So if a patient has prolonged vomiting due to something like hyperemesis, which I had
- and I had a lot of vomiting - that can definitely cause metabolic alkalosis.
In addition, prolonged NG tube suctioning and excess diuretic therapy can also result
in metabolic alkalosis.
In terms of symptoms, a patient who has metabolic alkalosis may have tachycardia.
They may have dysrhythmias as well as muscle weakness and lethargy.
In terms of treatment, we're really going to want to treat the underlying cause.
So if the underlying cause is prolonged vomiting, then we're definitely going to give the patient
anti-emetics for that vomiting.
If the patient is just taking too many TUMS, we're going to have to really educate them
and make sure they don't do that again.
And then it's going to be really important that we replace lost fluid and electrolytes,
so definitely you want to pay attention to those labs and replace the patient's fluid
and electrolytes as ordered.
So that is it with the deck [of flashcards].
Like I said, it's a nice thin deck, 15 cards.
And in my next video, I'm going to start running through a variety of practice problems to
really help you get comfortable with ABG interpretation.
Thanks so much for watching!