COPD (& Emphysema) Explained Clearly - Pathophysiology & Diagnosis

WEBVTT
Kind: captions
Language: en

00:00:00.510 --> 00:00:04.080
Welcome to another MedCram lecture.
00:00:04.080 --> 00:00:13.200
We're going to talk about emphysema today,
otherwise known as C.O.P.D.
00:00:13.200 --> 00:00:18.660
It seems as all these diseases have abbreviations
in medicine.
00:00:18.660 --> 00:00:22.660
This one is "chronic obstructive pulmonary
disease."
00:00:22.660 --> 00:00:24.250
What is C.O.P.D.?
00:00:24.250 --> 00:00:32.369
It's a common preventable and treatable lung
disease and the typical symptoms that you'll
00:00:32.369 --> 00:00:46.879
see in patients with emphysema C.O.P.D. is
shortness of breath, and you'll also see cough,
00:00:46.879 --> 00:00:50.909
and if it's wet you'll have sputum as well.
00:00:50.909 --> 00:00:56.629
These are very nonspecific symptoms, but they're
very typical of what you see in C.O.P.D.
00:00:56.629 --> 00:00:59.039
How important of a disease is this?
00:00:59.039 --> 00:01:12.670
Couple of statistics that you should know
is it's the third most common cause of death
00:01:12.670 --> 00:01:15.310
in the US; pretty significant.
00:01:15.310 --> 00:01:23.910
There's a number 2 and there's a number 1
above it and that's heart disease and cancer
00:01:23.910 --> 00:01:27.610
and sometimes these, depending on how you
survey, will flip spots.
00:01:27.610 --> 00:01:29.280
There's also number 4 and number 5.
00:01:29.280 --> 00:01:35.510
The key here is that this is the only cause
of death in the United States out of these
00:01:35.510 --> 00:01:45.000
5 that have actually gone up from about 2007
to 2010 all the others have gone down in frequency
00:01:45.000 --> 00:01:46.070
except for this one.
00:01:46.070 --> 00:01:51.260
This is a pretty significant disease that
we've got to be concerned about.
00:01:51.260 --> 00:02:02.530
In addition to all of this, it's also the
second leading cause of disability.
00:02:02.530 --> 00:02:09.090
Okay, so the bottom line here is that this
is a very important disease to know about.
00:02:09.090 --> 00:02:14.579
In case of course, you're wondering how much
of this costs the US healthcare system in
00:02:14.579 --> 00:02:23.099
the United States every year, the answer is
about 50 B with a billion; 50 billion with
00:02:23.099 --> 00:02:31.489
a B. That's quite a lot of money
As I mentioned, C.O.P.D or emphysema is a
00:02:31.489 --> 00:02:33.620
disease that affects the lungs.
00:02:33.620 --> 00:02:42.029
Specifically, if you were to take a look your
lungs, you of course know that your lungs
00:02:42.029 --> 00:02:47.610
have 2 sides and that there's a major airway
call the trachea and it branches off into
00:02:47.610 --> 00:02:50.529
the right and left main-stem bronchus.
00:02:50.529 --> 00:02:54.599
From there it just goes down to smaller and
smaller branches, without getting into too
00:02:54.599 --> 00:02:55.599
much anatomy.
00:02:55.599 --> 00:03:01.069
If we were to take these very small bronchioles
or respiratory bronchioles they would eventually
00:03:01.069 --> 00:03:09.840
end in a grape like cluster called a alveolus.
00:03:09.840 --> 00:03:13.260
This essentially increases the surface area.
00:03:13.260 --> 00:03:17.299
This is what a normal respiratory bronchioles
would look like.
00:03:17.299 --> 00:03:22.709
If you were to take all these alveoli in the
entire lung and spread it out it would be
00:03:22.709 --> 00:03:29.349
about the size of a tennis court.
00:03:29.349 --> 00:03:36.439
It's pretty big.
00:03:36.439 --> 00:03:42.040
These bronchioles of course allow the air
that you breathe in to go down and cause gas
00:03:42.040 --> 00:03:43.040
exchange.
00:03:43.040 --> 00:03:46.359
Now C.O.P.D. affects 2 main areas.
00:03:46.359 --> 00:03:52.930
It affects this bronchus, the small bronchial
and it also affects the alveolus in a bad
00:03:52.930 --> 00:03:54.810
way.
00:03:54.810 --> 00:03:59.659
What happens, is because the elastic fibers
are destroyed, we'll get into that later,
00:03:59.659 --> 00:04:05.370
is that that airway becomes very collapsible
and essentially it becomes very small, and
00:04:05.370 --> 00:04:08.799
that's where the obstruction in C.O.P.D. comes
from.
00:04:08.799 --> 00:04:15.579
Furthermore, you're also going to get destruction
of the alveoli and you lose a lot of surface
00:04:15.579 --> 00:04:21.440
area, so instead of having a nice tennis court
you end up with maybe a badminton court or
00:04:21.440 --> 00:04:25.660
even a table tennis court here that you're
working with.
00:04:25.660 --> 00:04:31.420
The surface area becomes much smaller and
all these changes happen throughout the lung,
00:04:31.420 --> 00:04:34.640
but mostly in the upper regions of the lung.
00:04:34.640 --> 00:04:37.340
As a result of that it's hard to get the air
out.
00:04:37.340 --> 00:04:42.850
There's an obstruction, that's the key point
there is that air cannot get out of the lungs.
00:04:42.850 --> 00:04:46.520
That's why it's called chronic obstructive
pulmonary disease.
00:04:46.520 --> 00:04:52.780
In addition to that because these alveoli
are all destroyed and become areas of large
00:04:52.780 --> 00:04:59.160
balloons if you will, the long actually increases
in size and as a result of that you get these
00:04:59.160 --> 00:05:04.150
patients with large lungs but they're full
of air and they can't get the air out and
00:05:04.150 --> 00:05:07.030
that's basically C.O.P.D..
00:05:07.030 --> 00:05:13.210
The way that we diagnose C.O.P.D. is based
on this obstruction.
00:05:13.210 --> 00:05:17.270
We set them down in front of a spirometer,
that's basically a machine where you breathe
00:05:17.270 --> 00:05:20.150
into it and it measures how much you breathe
00:05:20.150 --> 00:05:29.740
We asked them to basically breathe out after
taking a deep breath in, breathe out as much
00:05:29.740 --> 00:05:41.560
air as they possibly can and we measure it.
00:05:41.560 --> 00:05:46.880
This represents how much air they can blow
out given enough time to blow it out, so we
00:05:46.880 --> 00:05:50.571
give them 6 to 10 seconds to blow it out enough
time that they need to blow everything that
00:05:50.571 --> 00:05:53.110
they possibly can out in the lung.
00:05:53.110 --> 00:06:01.810
We call that, by the way, the forced vital
capacity.
00:06:01.810 --> 00:06:04.270
Otherwise known as the FVC.
00:06:04.270 --> 00:06:07.320
That's how much air they can blow out completely.
00:06:07.320 --> 00:06:11.460
We said that C.O.P.D. is an obstructive lung
disease so what we're really looking for is
00:06:11.460 --> 00:06:15.390
how fast can they get that air out, because
if there's an obstruction that's going to
00:06:15.390 --> 00:06:20.950
impede their ability to get that air out as
fast as they possibly can.
00:06:20.950 --> 00:06:24.830
The next thing that we do is that we have
them do the same maneuver, but we measure
00:06:24.830 --> 00:06:35.720
how much comes out in 1 second, so there's
kind of a timed proportion to this.
00:06:35.720 --> 00:06:40.090
How much can you blown out given an infinite
amount of time?
00:06:40.090 --> 00:06:45.240
And how much can you blow out in just 1 second?
00:06:45.240 --> 00:06:49.280
There's a little bit of a velocity factor
involved there.
00:06:49.280 --> 00:07:02.250
What we do is, we call that by the way, the
forced expiratory volume in 1 second.
00:07:02.250 --> 00:07:04.970
This is otherwise known as the FEV1.
00:07:04.970 --> 00:07:15.310
Then we do a very simple calculation, we measure
and we see.
00:07:15.310 --> 00:07:21.060
We take this number, the forced expiratory
volume and we divide it by the forced vital
00:07:21.060 --> 00:07:24.190
capacity number and we come up with a fraction.
00:07:24.190 --> 00:07:33.160
This is known as the FEV1 divided by the FVC
ratio.
00:07:33.160 --> 00:07:42.460
The definition that's come up in the literature
is that .70, 0.70 is the cutoff.
00:07:42.460 --> 00:07:53.050
If the FEV1 divided by the FVC ratio is less
than .70 that means that you could get less
00:07:53.050 --> 00:07:57.530
than 70% of the air that you could normally
get out, given an infinite amount of time,
00:07:57.530 --> 00:07:59.730
out in the first second.
00:07:59.730 --> 00:08:03.150
That means you've got obstructive lung disease.
00:08:03.150 --> 00:08:07.980
If you can get more than .7 out that means
you don't have obstructive lung disease.
00:08:07.980 --> 00:08:13.620
The question here is, can you get out at least
70% of the air that you could normally blowout
00:08:13.620 --> 00:08:18.580
in the first second, and if the answer is
yes then you don't have obstructive lung disease.
00:08:18.580 --> 00:08:24.770
If the answer is no and it's less than .7,
then you have obstructive lung disease.
00:08:24.770 --> 00:08:35.210
Of course, the lower this number is, the FEV1,
the worse your C.O.P.D. is going to be.
00:08:35.210 --> 00:08:37.409
Let's review.
00:08:37.409 --> 00:08:51.640
C.O.P.D. is 1) common, it costs a lot; 2)
it's the third leading cause of death and
00:08:51.640 --> 00:09:00.320
is the only 1 of the 5 that are actually increasing
in frequency; 3) causes difficulty with breathing
00:09:00.320 --> 00:09:09.250
out, that's obstruction; 4) reduces the cross-sectional
surface area, causes drops in oxygen; 5) you
00:09:09.250 --> 00:09:19.920
diagnose it by spirometry, and then finally
6) the diagnosis is the FEV1 divided by the
00:09:19.920 --> 00:09:24.550
FVC is less than .7
Thank you for joining us.
Office location
Engineering company LOTUS®
Russia, Ekaterinburg, Lunacharskogo street, 240/12

Phone: +7 343 216 77 75

E-mail: info@lotus1.ru

Sales phone

Russia: +7 343 216 77 75

WhatsApp: +79122710308