00:01
The subject of this lecture is pleural disease,
by which we mean pleural effusions which can
be transudates or exudates or infective in origin.
In addition, we’ll talk about pneumothorax
which is air in the pleural space and pleural
thickening. Mesothelioma which is a primary
cancer of the pleura is actually discussed
in the lung oncology lecture. There are a
couple of important basic concepts about pleural
disease. The first is that there are no divisions
in the normal pleural space. That means that
when you have a pneumothorax with air in the
pleural space, it will rise to the top, whereas
if you have pleural fluid, then it will sink
to the bottom and pleural effusions are best
detected at the base of the lungs.
00:40
However, if you get an infection in the pleural
space or a hemothorax that is blood in the
pleural space or a surgeon has done some pleural
surgery, then you get adhesions forming between
the visceral and the parietal pleura. And
that can cause loculations of the pleural
space divisions, and that will make the X-ray
appearances of pleural fluid or pneumothorax
quite different. The other basic concept of
pleural space is under negative pressure,
and this keeps the lungs inflated. That means
that when you get a pneumothorax, the lung
will collapse. Pleural disease is actually
readily detectable
normally by clinical examination. The stethoscope
will quite easily pick up a difference when
somebody has a pneumothorax or pleural effusion
between the affected side and the normal side.
01:29
And percussion will readily pick up somebody with
a large pleural effusion. The best test is
actually a pleural ultrasound, and that is the
most efficient way of assessing for pleural
fluid and for divisions in the pleural space
and is also affected by identifying whether
there are any masses or abnormality of the
pleural surface itself.
01:52
So pleural effusions, fluid in the pleural
space. This is an X-ray, on the right hand
side, of somebody with a left pleural effusion
that should be readily detectable clinically.
01:59
And you can see it quite easy on the chest
X-ray. These are very common and they occur
in multiple different specialties because
if the causes are very large range, it will
be seen by multiple different medical specialties.
The presentation is either as an asymptomatic
finding on a chest X-ray or as the effusion
gets bigger, the patient becomes more and
more breathless. So that causes progressive
dyspnoea over days or weeks.
02:25
Sometimes with the more inflammatory types
of pleural fluid, those which are caused by
infection or perhaps a pulmonary embolus,
then pleuritic chest pain is actually a very
prominent symptom. Pleuritic chest pain is
very specific and very easily characterized.
02:39
It’s a pain that occurs on inspiration and is
localized to where the inflammation is occurring
normally on one side of the chest. And you
may hear a pleural rub over that area.
02:52
So when you examine somebody with a pleural
fluid, what you will find is that the trachea
of large effusions may be deviated away from
the affected side. The expansion of the lung
with a pleural fluid around it will be reduced.
And when you percuss, it will be very dull
over the pleural fluid because the air has
been replaced by liquid, and that’s described
as stony dull because it’s very dull indeed.
You won’t be hearing any breath sounds,
and vocal resonance will also be reduced over
the area of the effusion. Sometimes at the
top of the effusion, you may hear an area
or patch of bronchial breathing, and, of course,
you may hear a pleural rub that is inflammation
of the pleura. But that will be heard with
the visceral, and the parietal pleura are
actually allowed to pose each other. Therefore,
it won’t be heard of the areas of large
effusions but areas where the effusion are
much smaller. There may be also signs
of what the cause
of pleural effusion is. So for example, there
may be palpable lymph node, somebody has got
a cancer or an enlarged liver, if somebody
has a cancer with liver metastases, there
might be signs of chronic liver disease, heart
failure, or rheumatoid arthritis. All of which
are associated with pleural effusions in
some patients.