00:00
So these masks, they are really tight fitting so that's something else patients have to get
used to. Now with CPAP, it might cover just their nose, it might be both. The patient will work
with the healthcare provider to find the most appropriate mask that they're willing to tolerate.
00:17
So, it gives that constant continuous pressure similar to PEEP but it's that positive
end-expiratory pressure. So, this is kind of similar to what we use PEEP on a ventilator.
00:29
Noninvasive is a modality, so we call it a ventilation modality, it's just a fancy word for saying
it's one of the options. Remember that it supports breathing because positive pressure means
that it's blowing in at a certain rate depending on our settings. Comes from a machine and you
don't need to intubate or do any surgery. So, this is it for patients who had a trach, you don't
have to do any procedures on them, they don't have to be intubated, they can just wear a
really tight-fitting mask that has to be the appropriate size for that individual patient.
01:04
Okay, let's do some FAQs about CPAP. Wow, we've got a lot of letters thrown in there. So, is
there oxygen with CPAP? Hey, good question. Not usually, it's usually just the continuous
positive airway pressure. See most people, if we can keep those airways open, their lungs can
take over. They'll increase the amount of oxygen that's available in the blood just because
now those airways aren't shut up or obstructed, they're wide open. Now, can you use oxygen
with CPAP? Yes, you can. Some patients need just a little more oxygen as a supplemental aid.
01:42
So there's a special oxygen bleed-in adapter. That will help allow oxygen to be attached to the
CPAP machine. So sometimes you may see a patient who has some oxygen attached to their
CPAP. Now CPAP, as usual settings are 5, 7.5, or 10 cm of water. Now, we don't often measure
things in cm of water. So in case you're not a physics genius and I clearly am not a physics
genius, I want to give you a little bit of a frame of reference. What does it mean to be 5, 7.5, or
10 cm of water? So let's take a look at 10 because that's a nice round number. Let's look at
what 10 cm of H₂O means with CPAP. Okay, so a cm of water is a unit that we use to measure
the amount of pressure. 1 cm of water is 0.0142233 pound-force/square inch. So that might
sound familiar to you, PSI. So 1 cm is 0.014, 5 cm is 0.07, 10 is 0.14, 15 cm is 0.21. Now how I
remember this and this is kind of a random FAQ because you're not ever really going to use this
in real life. It's important that you remember usually 5 or 10 is pretty average for settings
with a CPAP, but the physician can adjust those ratings up or down based on the patient
needs. But I usually remember it starts at 0.014 and then it's 0.07, 0.14, 0.21, all dividable by
the number 7. So, again that's trivia, the most important concept that you want to remember
is that the usual settings are 5, 7.5, or 10 cm of H₂O. Now we gave you kind of a frame of
reference to see what that is, but don't memorize those numbers. Because the aim of CPAP is
we want to keep those airways open. We want to reduce the collapsing of the alveoli and we
want to help those alveoli recruit and increase the volume of air that's present in the lungs at
the end of passive expiration. So when we have that CPAP, keeping those airways open we
want to make sure that we have extra volume of air present in the lungs at the end of passive
expiration. That's the definition of the functional residual capacity. Now you always see a
short in that to FRC. Now we're not talking about air trapping, we're talking about the normal
healthy residual capacity that you want to have in your lungs. That's too low for patients that
have obstructive sleep apnea but by using the CPAP we can get them to the appropriate
functional residual capacity. So before we move on, make sure you're underlining what
functional residual capacity is. I pause the video, kind of practice that definition a few times
just to make sure that it's solid in your mind. Now, based on what you know about CPAP and
BiPAP, let's create a chart. This is a cool strategy for helping your brain organize information,
see it in the consistent pattern and will make it easier for you to remember. Difference between
CPAP and BiPAP. Are they noninvasive ventilation? Both are considered noninvasive ventilation.
05:18
Remember nothing goes in to the patient, it's all external, delivered by a mask, connected to a
machine. Do they use a tight-fitting mask? Yes and yes. They both use masks. Now what about
cm of water? Is that what the settings are on both? Yes. Okay, so we've got 3 pieces of
information chunked together knowing that they are the same for both CPAP and BiPAP. Now,
positive pressure ventilation is constant with CPAP; 2 levels for BiPAP, 1 for inspiration,
1 lower for exhalation. So write the word lower by exhalation just to remind yourself if you're
new to this topic. Now can we use oxygen? Well not usually with CPAP, but we can add an
adaptor if it's necessary for the patient. For BiPAP, yes. We use it for patients who cannot
maintain an adequate arterial oxygen tension PaO₂ without assistance. Alright, now this is a
really cool tool when you're studying information, you're trying to look at the similarities and
differences for something, just make a quick chart in your notes. It's a great way to organize
that information for retention and recall.