0:01

Well, hi, it's Mark again.

0:02

Next, uh, segment in our cardiopulmonary,

0:06

um, curriculum is we're going to

0:08

talk about acute consolidation.

0:10

So these are diseases that present with a

0:13

consolidative opacity, which I like to kind

0:15

of affectionately call the clouds in the lung.

0:19

So, acute consolidation, clouds in the

0:22

lung, and it is actually when you have

0:24

an increased area of opacification, okay,

0:28

that causes the vessels to become obscured.

0:30

Because remember, it's all about differences

0:32

in density, and when the density of the lung

0:35

is the same as the pulmonary arteries, we

0:37

don't see the pulmonary arteries or veins.

0:39

Okay.

0:40

So we're going to review some of the

0:42

imaging appearance of consolidation.

0:45

We're going to look at some of the various

0:46

pathologies that are commonly seen that

0:49

present with acute consolidation in the lung.

0:51

And I'm going to emphasize the importance of air

0:54

bronchograms and air bronchograms we see in the

0:57

consolidation because the surrounding parenchyma

1:00

is now opacified, and there's still air

1:04

that's in the airway.

1:05

So now we don't see the pulmonary

1:07

vessels, but we do see the airways

1:10

as dark branching tubular structures.

1:13

And then lastly, we'll kind of look at the

1:15

differences of enhancement of consolidation

1:18

versus something like atelectasis on a CT scan.

1:21

So this is our concept map where we're going.

1:24

We're in the increased opacity and

1:25

we're going to go with consolidation.

1:27

As always, avoid the term infiltrate.

1:30

It is not helpful.

1:32

This is the concept map card that you'll have

1:34

access to, and we're going to be focusing

1:37

on this session with this one right here,

1:39

acute consolidation, blood press and water.

1:42

So, again, what are we doing?

1:44

We're looking at a radiograph, we're

1:45

checking the pulmonary vessels.

1:47

That's our, that's what we use as

1:49

our sort of standard of reference.

1:51

Are the margins sharp?

1:53

If they're sharp, that tells

1:54

us we got some aerated lungs.

1:56

And notice how we don't see airways

1:58

normally because they're filled with

2:00

air and the lung is filled with air.

2:03

So therefore, when we have a patient

2:05

like this, we don't see the vessels

2:08

very well, we see air bronchograms.

2:10

That tells us the disease process,

2:13

consolidation in this case, is in the lung.

2:16

As opposed to something like pleural effusion,

2:18

which causes an increased opacity of that

2:21

hemithorax. Opacity, but for the most part,

2:24

you can still sort of see the pulmonary

2:26

vessels and they're relatively sharply

2:29

marginated. And some of them here are not, but

2:32

these would be more, uh, suggested

2:34

that there is still air around those vessels

2:38

and therefore that opacification is likely

2:40

outside the lung, as opposed to the left

2:42

side, where the opacification is in the lung.

2:45

And this is a parenchymal process,

2:47

in this case, consolidation.

2:49

So what's your differential?

2:51

Acute consolidation.

2:52

And what I mean by acute is usually just

2:53

a rough rule of thumb, less than a week.

2:56

Um, pneumonia, bacterial, you know,

2:59

mycoplasma aspiration if it's dependent,

3:02

pulmonary edema, both sort of hydrostatic

3:05

and the acute lung injury spectrum.

3:07

And, uh, pulmonary hemorrhage.

3:09

These are sort of the main ones.

3:11

Now, I've put pulmonary infarct at the bottom,

3:13

and I'm going to have a special session just

3:15

with pulmonary infarct because that looks

3:16

a little different than these other ones.

3:20

So what is consolidation?

3:22

Well, let's go back.

3:23

When you see a consolidated opacity,

3:25

whether it's CT or radiograph,

3:26

and you have this consolidation

3:28

here, air bronchograms are present.

3:31

That often reflects,

3:33

pathologically, something we

3:34

call an organized pneumonia.

3:36

Now that's confusing because if you

3:38

say organized pneumonia to a clinician,

3:40

they're assuming it's infected.

3:41

It might be infected.

3:43

It might not be.

3:44

What it refers to is that there is

3:46

predominantly filling of the alveolar spaces

3:48

with some sort of inflammatory state,

3:50

usually neutrophils, maybe a little fibrin.

3:53

But you know, I want you to also notice

3:55

there's thickening of the interstitium.

3:57

So that's why airspace and interstitial

3:59

are kind of an artificial distinction

4:01

because both are often present.

4:04

Um, what's interesting about an organizing

4:06

pneumonia reaction is that it often

4:09

responds to corticosteroid therapy.

4:11

And for a lot of you, when you read these

4:14

COVID-19 patients with acute lung injury, when

4:17

that injury is predominantly consolidated,

4:19

and again, air bronchograms, they usually

4:24

reflect some more organizing pneumonia,

4:26

kind of acute lung injury.

4:28

And that would be something

4:30

you could treat with steroids.

4:32

They do tend to respond to that as

4:34

opposed to the more ground glass process.

4:38

That's more of a diffuse cellular damage and

4:39

that's a little bit more steroid-resistant.

4:41

It doesn't really respond to it.

4:44

So common case, uh, patient three

4:46

days in the hospital, you can see the

4:48

pulmonary vessels are sharply marginated.

4:50

But three days later, they have cough and fever.

4:53

You look at the right lower lobe, the

4:55

vessels become very difficult to see.

4:57

There are air bronchograms present.

4:59

This is a right lower lobe consolidation.

5:01

Don't say infiltrate, just say consolidation.

5:04

In the acute setting, it's

5:05

blood, pus, and water.

5:07

Um, it's not water if it's just focal like that.

5:09

I guess it could be hemorrhage, but most

5:11

likely, you know, it's a bacterial pneumonia.

5:14

And it was.

5:15

Another patient, very extensive

5:17

amount of consolidation.

5:19

You see the air bronchograms.

5:20

This is a bilateral perihilar.

5:23

Um, this was actually an aspiration

5:25

based gram-negative infection.

5:27

Pneumonia.

5:29

You don't need to say airspace.

5:31

Both are present.

5:31

Just call it a consolidation.

5:33

Differential is blood, pus, or water

5:35

if the symptoms are less than a week.

5:38

Patient 190 days post stem

5:40

cell bone marrow transplant.

5:41

Have a large consolidation bronchograms present.

5:47

Does have acute pleuritic chest pain.

5:49

This consolidation was most

5:51

consistent with a bacterial pneumonia.

5:55

Another patient widespread kind of

5:57

ground glass and consolidated opacities.

6:00

There are bronchograms.

6:02

The CT shows it nicely.

6:05

Beautiful air bronchograms present.

6:07

There's no pleural fluid.

6:08

This was a patient with a pulmonary

6:10

vasculitis and pulmonary hemorrhage syndrome.

6:13

So again blood, pus, or water.

6:17

And a patient with trauma, multiple chest

6:19

tubes, numerous rib fractures, large

6:21

consolidation in that left upper lobe.

6:23

What is that consolidation?

6:25

Most likely it's blood contusion.

6:27

Right.

6:28

Also notice that the mediastinal density is

6:30

way too high here and you can't see the arch.

6:33

That means that they probably have

6:35

and they did have a large mediastinal

6:37

hematoma from an aortic injury.

6:41

Okay.

6:42

Another form of consolidation that's a

6:44

little bit more tricky is it is when it

6:46

has that kind of five to 10 millimeter

6:49

ill-defined nodular appearance that

6:51

coalesces, so called acinar nodules.

6:54

Um, it's still consolidative.

6:57

And the other thing that's really

6:58

important about this particular patient

7:00

is the consolidation is diffuse.

7:02

In the acute setting, a diffuse consolidated

7:06

process often reflects an etiology

7:09

injury that comes from outside the lung.

7:12

A systemic, in this case it was

7:13

sepsis, a TRALI could do it and such.

7:16

It damages the lung uniformly and it tends

7:19

to present in a very uniform diffuse pattern.

7:24

Patient with consolidation, both

7:26

lower lobes with air bronchograms.

7:28

Ill-defined, dependent, what would you think?

7:33

Well, blood pus or water, I don't

7:36

really care for it for water.

7:38

The vessels look sharp in the

7:39

perihilar regions where I do see them.

7:41

This is more of a lower lobe consolidation and

7:44

dependent, you would consider an aspiration

7:47

based pneumonia or an aspiration pneumonitis.

7:51

This is what air bronchograms look like.

7:53

They do take a while to develop that eye to

7:56

pick them out, but when you see them, that

7:58

helps, it's very helpful with a consolidation.

8:01

Remember now, atelectasis can give

8:03

you air bronchograms too, but they

8:05

are often very crowded together.

8:07

Here they are separated.

8:10

This patient had influenza A and developed

8:13

a right middle lobe consolidation.

8:15

This one does not have air bronchograms

8:17

and we're going to talk about that

8:18

in the next section, but that kind of

8:20

suggests things like infarcts, drowned

8:23

lung, and necrotizing pneumonia.

8:26

That was a staph pneumonia

8:27

and it was necrotizing.

8:29

When it necrotizes,

8:30

air bronchograms tend to be absent.

8:33

Lastly, you have a CT scan.

8:36

And you enhance it.

8:38

What you want to do is look at that paraspinal

8:40

muscle, then look at what's enhancing.

8:44

Is it the same as the paraspinal muscle?

8:47

Yes.

8:48

That's a consolidation.

8:51

Atelectasis, the vessels all come together

8:54

and there's much more of a blush of contrast.

8:57

It enhances greater than the paraspinal muscle.

9:00

So rather than just saying, well, it

9:01

could be atelectasis or consolidated

9:03

pneumonia, you look at the enhancement,

9:05

you go based on the enhancement.

9:07

This is atelectasis, and this is a

9:09

consolidation, presumably a pneumonia.

9:14

So summary, consolidation represents

9:16

an ill-defined opacification that

9:18

completely obscures the vessels.

9:20

It is a descriptive process.

9:22

It often reflects an organized

9:24

pneumonia, but hemorrhage and edema

9:26

can occasionally also give it.

9:28

Absence of air bronchograms is usually

9:30

seen in the setting of drowned lung,

9:31

necrotizing pneumonia, and infarcts

9:33

we'll talk about in the next segment.

9:35

And.

9:36

With enhancement, consolidation will

9:39

enhance the same as the paraspinal, atelectasis

9:42

enhances greater than the paraspinal muscles.

9:45

As always, try to avoid the word

9:47

infiltrate and airspace and interstitial.

9:51

I don't use it.

9:52

Doesn't really help.

9:53

Thank you so much for

9:54

listening and, uh, take care.