Evaluation of the Lung and Pleura: Outline - SD

Introduction

Hello, I'm Anthony Dean.
I'm the director of the Division
of Emergency Ultrasound in the emergency department at the
University of Pennsylvania in Philadelphia,
in Pennsylvania, United States.
Today we're going to talk about the assessment
of the pleura
and lungs,
as well as pleural effusions, with ultrasound,
and its use with critically ill patients
and a certain emphasis on
new developments in the field.
Without further ado, let's
start the lecture.

This lecture will
cover some topics that have
been covered previously,
but we'll represent some updated information about
use of lung ultrasound
in the critically ill.
We're gonna look at pneumothorax,
wet lung consolidation and pleural effusions.
We will not be considering
thoracentesis and
procedural applications, ultrasound in the lung
and pleura
in this lecture.

Diagnosis of Pneumothorax

Initially to review the use
of ultrasound in the diagnosis of pneumothorax,
we have two layers of pleura that are the parietal
and visceral where the parietal pleura
intimately opposed
and fixed to the chest wall
and the visceral pleura
fixed
to the lung underneath it.
In the living state,
these two layers
slide past one another
every time any
of us takes a breath.
This finding can be identified on ultrasound
and is the basis of the
diagnosis of pneumothorax,
which will be the absence of this sliding.

Here is the fundamental anatomic picture.
When we
do ultrasound
to diagnose pneumothorax, the actual technique consists
of placing the probe
perpendicular
to the ribs as is shown here.
The probe is in a longitudinal plane,
perpendicular to the ribs,
allowing us to
identify the ribs and the rib shadows.
We've seen right here.
Based on the ribs
and the rib shadows, we are going to use that information
to identify the pleural line,
which
once it's shown
seems quite easy to recognize.
But should we note that there are several other lines here
that could be a source of confusion.
It's important to rigorously define the rib
and the lower extent of the rib, if you can.
The line that runs
underneath them is the pleural line,
which we're going to be examining.
If you have an ultrasound machine that has a
focal
adjustment, the focus should be adjusted
to about the length of the depth of the focal line,
which most people is about three
to five centimeters deep.
You can see in this image, that's
what this triangle represents.
If you have a machine
that does not have focal adjustment,
most
of those machines
automatically place the focus in the middle of the screen.
The pleural line should be placed approximately in
the middle of the screen.
Here's an enlarged image over here
of the same, the one we've seen
before the pleural line over here.
We can see the same thing here.
The ribs can be seen here and here.
The shadowing in these images is less
pronounced than it was
over in this image right over here.
Nevertheless,
we can see the kind
of underside of the ribs right along here.
So this will represent the pleural line,
going right through here.

Where are we going to scan?
We're actually going to
place the probes we've mentioned in
the longitudinal plane,
and we're going to scan every rib space that we can find,
starting immediately below the clavicle
and going all the way down
until we run into the diaphragm on the left.
If we're using the midclavicular line, which we use,
which is the appropriate line in supine patient to use,
if we use it on the left, we sometimes encounter the heart
at a certain point,
in which case the probe swings out, it's brought out
to the anterior axillary line,
and continues all the way down until, once again,
the diaphragm is encountered.
You can certainly
scan rib spaces in other areas
of the chest if you're concerned about anterior
pneumothorax, or have some other reason to believe that
the pneumothorax
might not have been adequately imaged
or identified in these particular planes.

How is the diagnosis made for pneumothorax?
First of all,
like similar to
as is the case with
ectopic in first trimester pregnancy,
to a certain extent, the pneumothorax is excluded
by the identification of normal findings.
The normal findings are pleural sliding,
pleural based comet tail artifacts,
which we'll talk about more extensively in
the next part of this lecture.
Pneumothorax is identified by the absence
of pleural sliding in any rib space
and or the leading edge sign,
which we'll discuss in more detail.

This is normal expanded lung.
We have rib shown here.
It's a very thin rib, and then we see this line going
right underneath it here.
In this rib space,
we can see this line sliding back
and forth from left to right of the screen.
With little pleural defects
and abnormalities
underneath the pleural line indicating
the presence
of the visceral pleura abutting the parietal pleura
for a normally expanded lung.
Down here, we have an M mode rendition of this image.
What happens when you put m mode down through
this rib space here is that the
tissues down from the skin down to the pleural line
are essentially linear
because there's continuity of those echogenic interfaces that's continuous through time,
so that you get a pretty much continuous
fairly linear looking pattern here.
Beyond the pleural line, as a result
of the movement down here of the lung tissue,
similar to the movement that can be seen right here,
which is very regular, you end up
with this much more granular looking region down here,
indicating the presence of lung.
For shorthand, this has sometimes been described as
waves on shore, waves on the beach.
The sandy beach here is a bunch
of waves coming down towards it
that look fairly linear.
So you've got this granularity referred to as this,
the sands of the beach.

Here's another case of using a phased array probe.
Again, these are comet tail artifacts
or beelines that are originating from the pleural
surface here and going back and forth with pleural sliding.

Now, pneumothorax,
as we mentioned
before,
initially is shown with absence of these findings.
Here, here's a rib.
Here's a rib shadow, another rib over here in rib shadow.
These are the intercostal muscles
here with their fascia.
This is the pleural line right along here.
This pleural line is very linear.
It doesn't have any of that granular movement
along the surface here, and that's
because the visceral pleura
is absent from the
continuity with the parietal pleura.
Therefore, the ultrasound
machine transducer cannot detect it.
This is the signature of this is a very smooth,
unchanging line.
Looking down here at the B mode image that's generated
by this, the tissues that go down
to the pleural line, once again, are like the waves
that are approaching the beach.
They're very linear. They're very continuous.
But now, instead of the sand, which had
that very granular appearance, we now have more linear
signature down here as well
with much less granular figure.
This image right here is often described as the stratosphere sign
because there's straight lines all the way across.
Also sometimes called a barcode sign
because sometimes these lines appear very similar
to the soft tissue lines up in this area here.

Now, the other finding for pneumothorax,
and we mentioned there are two of them.
One is the absence of pleural sliding.
The other one is what we call the leading edge sign,
which is the presence
of the actual transition point between collapsed
and expanded lung under the ultrasound probe.
In this image here, you can see this lung sliding
that's on this side
of the rib space that's going back and forth.
Over on this side here, there is absence
of lung sliding throughout the respiratory cycle.
This represents the very edge, the leading edge
of the pneumothorax,
or actually the leading edge of the expanded lung,
moving back and forth across this rib space.
Obviously, if this is identified, then it's possible
to get a sense of the extent of the pneumothorax by
following this around on the chest
and finding out how much roughly of the chest is
in the condition of pneumothorax,
and how much of it is with expanded lung.

Updates and Consensus on Pneumothorax

The updates that this lecture are going to include are some
preliminary findings.
These are not finalized
and are not published yet.
Or there are plans to publish
them in the near future.
Today's date being May 13th, 2011.
There has been a consensus conference has been held using the modified
Delphi technique under the aegis of wind focus.
The conference was held in various cities in Rome during 2010
and early 2011.
Using this technique,
which I'll describe briefly,
consensus ideas about the use of lung ultrasound are
rapidly emerging.
The process consists first of identifying experts
and stakeholders on the topic.
A literature on the topic is
developed by essentially including everything that's been written on it.
Then the experts and stakeholders are given the chance
to review all the literature.
In this case, we found about 250 journal articles
and round table discussions then ensue face to face.
As can we see in this image, is actually one
of the discussions in this image is actually presenting
his thoughts from New York in the one
of the consensus conferences that was held in Rome.
The propositions are developed by the experts
and the panelists, the members
of the expert panel,
render opinions on those propositions.
Scoring is done basically by
for each proposition.
A score of one to three essentially means
that the expert panelist thinks the statement
or proposition is wrong or inaccurate or flawed.
Three to six,
the expert feels neutral regarding the proposition.
Seven to nine the expert thinks the statement
or proposition is correct.
Propositions are measured with respect
to the average score of support.
You can determine what the overall support
for that proposition is,
and then also analyze with the spread of the number.
An average score of five
that's made up of half the people scoring a nine
and half the people scoring a one shows
that there's very little consensus.
Nevertheless, it gives the same average score
as something that everybody scores a five
and feels that there's no strong reason
to support or refute.
Once this process has been done once
and the scores are tallied, the conference
are given these scores
and given the opportunity to modify their opinion
based on how the rest of the group has felt about it
and have further debate for against
the proposition.

With respect to pneumothorax, there was,
in this instance, a selection
of the propositions that were came up with the group.
There's strong support
and good consensus on the statement that sonographic signs
of pneumothorax include the ones we've mentioned, presence
of lung point, absence of lung sliding
and gliding, absence of beeline, absence of a lung pulse,
which we haven't spoken about very much,
but is really the absence of the
movement in the lung generated by the
cardiac motion.
Another recommendation that was
another statement that was strongly recommended
and in a positive regard with good consensus was
that lung ultrasound when compared to supine chest x-ray,
maybe a better diagnostic strategy
as an initial diagnostic study.
In critically ill patients with suspected pneumothorax
may lead to better patient outcome.
There's no recommendation was made regarding the comparison
between lung ultrasound and CT in the assessment
of size of a pneumothorax.
It turned out the average score was 4.7
and a wide range of panelist scores.

Evaluation of Wet Lung

Now we will move on to
the evaluation of wet lung
and subsequently consolidation in the lecture.

The fundamental principle that's going to be
at play here is that normal lung is air-filled
and does not transmit ultrasound, which basically gave rise
to the original view that the lung was something
that was essentially sonographically occult
and would not be amenable to sonographic
interrogation.
It turns out that pathological lung
due to inflammation becomes fluid filled in various ways
that make it amenable to ultrasound,
or at least make changes
that could be recognized sonographically.

So the first step of the process
after injuries frequently interstitial edema,
the formation of interstitial edema,
and that's gonna give reverberation artifacts
at the gas tissue interfaces,
which we'll talk about in a second.
These reverberation artifacts are
called comet tails.
Lung rockets or beelines, injury can
go directly to alveolar fluid.
If you have bacteria sitting in your alveoli, staphylococcus
or streptococcus, then you'll develop a consolidated
pneumonic process.
Or sometimes interstitial fluid can itself progress through
to alveolar fluid, for example, with interstitial
congestive heart failure, which progresses to
alveolar infiltrates.
If there's sufficient progression
of the failure without therapeutic intervention.
The findings with alveolar fluid are of essentially a
fluid-filled organ
which transmits ultrasound.
The description of this is often
as a tissue or hepatization appearance,
because it actually does look much more like liver than
lung at this point.

Interstitial Edema and B-Lines

Starting first of all with the first component
of this, the interstitial edema, here is an image that shows
intensive beelines culminating actually in
an area which is showing a large pleural effusion
at the end of the clip here.
In the meantime, there are intense beelines apparent
or comet tails arising from the pleural line here.
There's also A lines described, E lines
and Z lines which we will not be dwelling on today.
The basis of this is thought to be that
the interstitium, the alveolar walls
and the interstitium of the lung when they become fluid
filled actually provide sufficiently dramatic impedance mismatch that
they become intensely echogenic
and result in ultrasound waves being reverberated back
and forth in within this space,
or possibly actually within the interstitial space
in such a way that they cause these reverberations,
because each time they bounce back towards the probe
a certain amount of the ultrasound waves get travel back to the transducer,
and the remainder of them continue to echo back and forth.
Each time they return
in this direction towards the probe, some sent back
to the transducer resulting in these very fine linear
rocket tail reverberation artifacts.

What are the number of beelines to be seen that
are considered to be pathological?
There's been quite a wide range of descriptions of this.
Beelines, particularly laterally inferiorly,
maybe normal
and up to six comet tails per side are found in 14%
of normal people by Dr.
Rei in one of her studies.
With multiple anterior comet tails in many rib spaces,
this is almost invariably an abnormality.
Two different kinds of beelines have been described,
first those that come straight from the
pleural line and are very closely based here.
These are considered to be
arising probably from alveolar walls right up contiguous with the pleura here.
On CT these are equivalent to the ground glass areas
of interstitial fluid that could be seen in this image here.
Some beelines appear to be more widely based.
Some people have actually measured the distance
between them
and sometimes they can be seen
to rise slightly deeper within the tissue.
Here's the pleural line here.
Some of these lines can definitely be seen
to be rising a little bit more deeply within the pulmonary
tissue, and they're probably
or they're putatively arising from engorged interlobular septa deeper down in the lung.
These two types of B-line are clinically
equivalent in most regards for practice, for patient management.
They both mean that there's excessive lung water,
extravascular lung water, which
needs therapeutic intervention
because it's causing decreased lung compliance
and impaired oxygen exchange.

Obviously, many things can cause a lung injury.
Ultrasound does not differentiate between them,
pulmonary edema, chemical mechanical trauma,
ARDS interstitial pneumonitis, or COVID.
Clinically these things are usually fairly
obvious in the patient's story.
It's not necessary
or ultrasound isn't really needed
to distinguish which they are.
But it does indicate that the presence of significant
lung trauma or
disease to have created this degree
of interstitial fluid to cause this number of beelines.

There's different techniques actually used
for counting beelines and assessing them.
As we've mentioned this, some disagreement
about details.
The simplest method is just
to look at two rib spaces on each side
of the chest anteriorly in this area here.
A more widely promulgated technique used by Dr. Volpicelli, which will be mentioned in detail
in a moment, has been developed.
Finally, there's
a very detailed technique in which 28 rib spaces
are evaluated in several lines in the chest on each side,
arriving at a composite score
of 28 rib spaces for the entire chest.

Dr.
Volpicelli is responsible for this system,
which has been fairly widely adopted
of dividing each hemithorax into four regions, as shown here.
The nipple line is the approximate dividing line
between the upper and lower.
A positive study according to Dr.
Volpicelli is that two
or more of these quadrants on both sides of the chest
have two or more beelines
and using that versus chest x-ray at least,
he's found that sensitivity
and specificity for pulmonary edema,
increased extravascular lung water is 86
and 98% respectively.
Versus clinical impression of ARDS,
the sensitivity and specificity is almost the same.
That probably reflects the fact that clinical impression
is very often based on chest x-ray.

We actually at university
of Pennsylvania looked at different
ways of scoring beelines.
The good news was we assessed them
with a gold standard of a composite clinical endpoint,
which included BNP and other studies performed by the patient,
either in the ED or after they admitted to the hospital.
The composite clinical endpoint was extracted
by two independent physicians making a
impression whether
or not the patient had been in congestive heart failure
or not at the time of the exam in the emergency department.
All these techniques performed very similarly
with respect to the receiver operator characteristic curves
as can be seen in this picture right here.

Another interesting investigation that's been done
of this by Dr. Noble
and her colleagues has really looked at
B-line scores, using the
more sophisticated 28 rib space technique
at before and after dialysis in a number of patients
and correlated it with the amount
of volume dialyzed off patients.
As can be seen here.
The number of beelines is almost exactly correlated with the amount of fluid removed from patients
before and after, or, sorry, rather during dialysis.
This actually brings up
important potential application of beelines in
monitoring therapy in patients who come in
with increased extravascular lung
water for any reason.
It appears that beelines develop quite quickly
and go away quite quickly in patients
who receive treatment.

In conclusion, some of the recommendations from the Lung Consensus Conference,
in patients with suspected interstitial syndrome,
a negative lung ultrasound exam is superior
to conventional chest radiography
in ruling out this diagnosis in the evaluation of interstitial syndrome.
The sonographic technique ideally consists
of scanning eight regions.
This is the Volpicelli technique
that I've mentioned, but more rapid anterior two region scan
may be sufficient in some cases, positive regions defined
by the presence of three
or more beelines in a longitudinal plane between two ribs
in any given lung ultrasound is able to monitor aeration changes
and the effects of therapy in a number
of acute lung diseases, including acute pulmonary edema,
respiratory distress syndrome, acute lung injury,
community-acquired pneumonia,
ventilator associated pneumonia recovery from lavage,
alveolar proteinosis,
semi-quantitative B-line assessment is a prognostic indicator
of adverse outcomes to mortality in patients
with acute decompensated heart failure.

Not everything in this consensus conference was met
with agreement and consensus and support.
There's no recommendation made regarding lung ultrasound used
as a first line diagnostic approach in the evaluation
of suspected interstitial syndrome when compared
to chest radiography may lead to better outcomes.
In other words, there's no agreement on that.
No recommendation will be made to that.
Pending further scientific investigation, a couple of,
more, I should say many of the panel's findings related
to pediatric lung ultrasound.
One example relating to
alveolar interstitial syndrome was that the sonographic sign
of transient tachypnea
of the newborn is bilateral confluent B-lines in the
dependent areas of the lung, a normal,
near normal appearance of the lung in the superior fields.
With respect to respiratory distress syndrome,
all the following sonographic signs are likely
to be present in neonates, pleural line abnormalities,
absence of spared areas, and bilateral confluent B lines.
Lung ultrasound is as accurate
as chest radiography in the diagnosis
of respiratory distress syndrome in neonates,
another finding.

Pulmonary Consolidation

So now we're gonna move along from wet lung
to actual pulmonary consolidation.
Just to review the normal
lung is air filled and does not transmit ultrasound,
but now we're going to focus on this area right down here
of alveolar fluid resulting in a parenchymal change in the lung,
making it fluid filled and giving it a tissue
or hepatization appearance.

Here's an example in this image right here,
one can see the pleural line right here,
and underneath this area of consolidated lung filled
with these white lines that move with respiration continuously don't disappear, which makes one know
that they're tubular structures.
It turns out these are air bronchograms as seen on ultrasound.
The other feature of pulmonary consolidation is
to notice, especially if caused by an inflammatory process like pneumonia, is that the distal side of the lung
or the transition zone between collapsed,
consolidated and normal lung, which is irregular
and gives rise to this very sort of jagged appearance,
often referred to as the shred sign.
So named by Dr.
Lichtenstein, and if this was an ultrasound probe placed
here in this patient's CT,
this area here would show up as a consolidation like this.
This area here would probably show up
as areas multiple beelines.
The back area of this consolidation here
with its irregularity
and its transition to increasingly
aerated lung will give this
shredded appearance with
these small reverberation artifacts coming down from here
caused by the interstitial edema in that region.

The differential of consolidation of these
finding these sonographic findings of first ARDS,
you might see fluid bronchograms to help distinguish,
and there might be fewer air bronchograms,
although the old idea that there would be no air bronchograms in
ARDS is not borne out, tumor,
it may be seen deep to consolidation or standing alone.
It again, it's will not have air bronchograms,
it will have internal flow throughout,
although it'll have less
or less augmented flow than inflammatory process such
as the pneumonia abscesses, pulmonary emboli can also be seen as consolidations of various forms,
as can pulmonary contusion after trauma.

So, another example here, a case someone who came in
with pericarditis chest pain in their back
before the chest x-ray was even done.
We obtained this ultrasound,
which clearly showed the consolidation, a chest x-ray
had been ordered
and returned with this lateral view here.
Actually initially read negative by the radiologist,
but I think this unquestionably an area
of consolidation back here.
Which on the chest x-ray could be confused with a
posterior costophrenic effusion.
Although I think a slightly regular margin here might argue against that.
Anyway, it's clearly seen here to be a consolidation right down in the costophrenic sulcus
right here we have the sort of transition between
alveolar interstitial syndrome with increased
interstitial markings and
sort of many beelines
and also reverberation artifacts originating right
through the thickness of the lung.
Trending into an area
of frank consolidation right here, where the lung can be seen to have a hepatization appearance,
again, as this loop flips through.
This is this area right here of lung that's consolidated.

Where's the probe gonna be placed to obtain these studies?
It should be placed anywhere
you might place a stethoscope.
There's certainly room for discretion here.
It's obviously the clinician's likely
to put the probe in places where the patient's complaining
of pain,
or if he's using this places
where a pleural rub may have been heard
or crackles, in one protocol.
Lichtenstein advocated placing it in two places in the anterior chest,
two places in the mid axillary line,
and two places in the posterior chest on each hemithorax.
We'll discuss his findings from that approach in a moment.

With respect to chest x-rays, we know chest x-ray has poor correlation CT findings
of effusion, alveolar consolidation, interstitial markings
and cardiac dimensions.
That's been demonstrated by several investigators.
Chest x-ray suffers from poor inter observer reliability
And is often non-diagnostic.

In comparison, Lichtenstein
used the ultrasound protocol I've just mentioned
in 32 patients who are being evaluated
for ARDS versus infiltrate and
consolidation in the critical care unit.
Ultrasounds were performed prior to the chest CT.
The 12 areas I mentioned were analyzed sonographically
and also analyzed with a stethoscope at discretion of the clinician.
The stethoscope was used by a separate
clinician who's blinded to the results
of the ultrasound, and obviously the chest x-ray
and was placed
where the clinician felt necessary on the chest.
Finally, a portable chest x-ray that was obtained,
which the results of which were blinded for everybody else doing the sonographic exam
or the systematic auscultation, and indeed the CT scan.
Accuracy was assessed
for each modality versus CT in the 12 areas,
times 32 patients.
That's 384 areas.
This is a kind of busy table,
but it essentially shows the percent agreement for each
of these diagnoses with the
between the various modalities and CT scan.
Auscultation, for example, had 42% sensitivity
for pleural effusion compared to CT,
for alveolar consolidation was actually very specific.
Chest radiography also had high specificity
for alveolar interstitial syndrome
and really pretty high specificity
for alveolar consolidations as well.
But in all respects for both pleural effusions,
alveolar consolidations
and alveolar interstitial syndrome, lung sonography
performed very well.
In the cases
where two observers did the lung sonography,
it was fairly high correlation between their impressions.

Another evaluation of the use of lung ultrasound
for identification of consolidation.
Soldati actually looked at patients
who sustained chest trauma
and excluded patients in whom pneumothorax had been
identified or had massive subcutaneous emphysema.
He actually looked for two different
findings after trauma.
First was alveolar interstitial syndrome using
the definitions very similar
to the ones we've already discussed.
The second was peripheral parenchymal lesions, one
of which can be seen here, which is essentially a
subpleural consolidation,
probably caused by contusion.
Basically the key findings were that the comet tails were highly sensitive
and specific for identifying AIS,
and the focal lung lesions noted were identified
with great specificity, although four
and five of them actually were overlooked,
so the sensitivity was pretty poor.
But if you see them,
they're definitely there indicating focal areas
of pulmonary contusion.

The Pleural Lung Consensus Conference findings on this,
among others were
that lung ultrasound is able to identify consolidation due
to the following causes, pneumonia, neoplasm, contusion,
ARDS, and infarct.
The lung ultrasound is a clinically useful
tool to rule in pneumonia.
However, lung ultrasound does not rule out consolidations
that do not reach the pleura.
I think most experts consider
that about 90% of consolidations reach the visceral pleura adjacent
to the parietal pleura that can be imaged.
Obviously, some consolidations will be adjacent
to the diaphragm or the mediastinum, neither of which
sonographically identifiable from
transthoracic ultrasound.

Pleural Effusions

Moving on now, finally, to pleural effusions.
We will not be considering thoracentesis in this module.
Pleural effusions are usually hypoechoic areas
with changes in thickness with respiration.
They do not move on M mode
and they may or may not be anechoic
and solid lung associated with them.

So right in this image here, we can see the spleen,
and going up above here, a big area of effusion with some
lung, extremely anechoic floating around in it and waving.
Of note, the diaphragm, it's much harder to see
adjacent to an effusion.
Sonographers
with less experience sometimes mistakenly call these
effusions, especially if they're a little smaller.
They call 'em subphrenic
because they're unable to identify the diaphragm
as clearly as they used to in many ultrasounds
because in fact, the bright white line
of the diaphragm is mainly caused by adjacent lung.
So when the lung is taken away, the diaphragm gives a much
weaker echo signal,
and it's sometimes not even easy.
It is impossible to see a tool in some areas,
as can be seen in this example here.

Here's another effusion to be seen on ultrasound.
Again, we're seeing the,
it's likely the liver here, I think, again,
might be the left side with spleen, I'm not sure.
Diaphragm, lung,
very anechoic floating in the effusion.

Effusions may have a complex appearance
initially with echoes, clouds
of layering white cells can be seen,
and oftentimes as these effusions organized
and reorganized, they may develop septations
and strands as can be seen in this case here,
many times which wave around with respiratory
movement, like sort of pieces of seaweed.

In the pleural effusion, here is a much smaller effusion.
Here we see the rib and the rib shadow, the pleural line's right here.
Right in here,
there can be seen just a very thin layer of effusion.
This is presumably right here is a fissure of the lung causing
that apparent step off.
Here, right here is the fissure, as I mentioned,
where there's some step off.
Down here is most likely an area of more extensive effusion butting up against the diaphragm
as we move inferiorly.
Here's the diaphragm down here.
Again, some internal complex echoes
of the effusion are right in here.

Technique for Pleural Effusions

Technique.
Ideally, the patient should be sitting in order to
place the effusion in a dependent area on the chest.
A couple of pearls and pitfalls.
Be careful with smaller effusions
when the patient's supine.
If you're scanning very laterally here,
your scanning plane might actually go straight over the top
of a small effusion back here in the pleural space.
Oftentimes when patients are supine,
actually recommend scanning more anteriorly here rather than
from the side, even though the
ultrasound probe is closer when it's down at this location
here, as I mentioned, sometimes it's impossible
to scan towards the back due to the orientation of the ribs.

Conclusion

Finally to conclude, we should
be aware
that there's an extensive literature has emerged over the last
five years, and even more remotely on lung ultrasound,
which is an area that until recently was viewed
as sonographically occult.
It's an evolving consensus on many applications.
Some are more rapidly mastered than others.
Utilization is likely to depend on practice setting,
personal experience, personal skill,
regional and sort of cultural standards
of care in one's community
and certainly resources at one's disposal.
I think lung ultrasound is
particularly useful in areas that
do not have other imaging modalities readily available
for assessment of the lung
and pleura, consensus process such
as the one I've been describing actually.
It's likely to promote scientific communication
and globally agreed standards.
It's gonna develop improved research.
I should give credit to the organization that
has actually been responsible for this
process and is extending its development of consensus documents on a number
of areas in sonography,
and that's the wind focus organization which
can be accessed certainly on the internet
to find out more about it.
They were responsible for the consensus conference that has
been discussed in this lecture.
Hopefully this lecture has been
of use and will be used by those
taking care of critically ill to evaluate the
lungs and pleura.