Moving onto the hands, I mentioned clubbing
is a very important respiratory sign. It’s
actually relatively rare but if somebody’s
clubbed you need to find the reason for that.
And the respiratory causes for that will be
lung cancer, bronchiectasis – especially
the severe end in cystic fibrosis – pulmonary
fibrosis and then occasionally, although this
is less common now we have routine antibiotic
use for infections, prolonged lung abscess
and prolonged empyema.
What we mean by clubbing is that the normal
angle of the nail bed has been lost. And the
reason why it’s been lost is it’s been
filled in by this spongy tissue. So there’s
two things when you examine a patient for
clubbing: one is that the nail curves over
and the second is that, when you squeeze that
nail bed, it feel spongy. It bounces a little
Now there are non-respiratory causes to clubbing
as well and these need to be considered if
you identify clubbing in somebody presenting
with respiratory problems. An example: it’s
not uncommon to come across somebody with
liver cirrhosis that is causing clubbing and
they have a respiratory disease which is pretty
independent of that.
So the non-respiratory causes: liver cirrhosis,
bacterial endocarditis, congenital cyanotic
heart disease and inflammatory-bowel disease.
And occasionally you get patients with idiopathic
clubbing. In fact, this x-ray is an example
of idiopathic clubbing. It’s clear. The
patient’s clubbed but there was no reason.
And they’re a relatively young patient with
no active problem that might explain why they’re
Moving on to the – examining the mediastinum:
mediastinal shift is a very important sign
is respiratory disease. And a shift of the
mediastinum occurs if one lung has been made
smaller or if that hemithorax has increased
in volume. So if you have a disease that makes
the lung smaller, that will pull the mediastinum
across and you can feel that when you’re
examining the trachea, as the trachea’s
being shifted to the affected side. And the
apex beat will also move with that. So that,
for a left-sided lesion, the apex beat will
move round the chest wall. For a right-sided
lesion causing a shift to the mediastinum
to the right, it will pull the apex beat across
towards the right. An increased volume on
a hemithorax will do the opposite. So it’s
a sign of a unilateral lung disease problem.
So the diseases that shift towards the abnormal
side is when you get collapse. A bronchus
has been obstructed and all the air distal
to that bronchus has been resorbed and that
lobe or that lung, if the main bronchus has
been obstructed, will collapse down and form
a smaller volume. And that will pull the trachea
The same thing happens with a pneumonectomy.
Of course, the patient with a pneumonectomy
or lobectomy will have a surgical scar as
well. And occasionally, you get the same thing
happening after severe destructive lung infections
– tuberculosis being the best example. Chronic
empyema can also cause something similar,
as can mesothelioma which, in the end stages,
cause a very restricted lung with pleural
thickening around the outside, getting smaller
and smaller compared to the other side.
The opposite – when you get mediastinal
shift away from the abnormal side largely
occurs with pleural problems. Either very
big pleural effusions or pneumothoraxes. And
there are the occasional very large pleural
lung tumours that can push the mediastinum
across. But they’re unusual.
Lung expansion: now this is different to hyperexpansion.
Hyperexpansion means that the chest is, as
you look at it, visibly bigger than it should
be. Expansion is the movement that occurs
on inspiration of the chest wall. So that
should be equal and about 2 or 3 cm in total.
But clearly, it depends to a certain extent
on the patient’s size. A small person will
have less expansion during inspiration than
a large person.
Expansion can only go down with pathology.
So the question with expansion is: is it normal
– equal expansion on both sides – or is
it reduced? And if it’s reduced then the
question is whether it is unilaterally reduced,
on one side, suggesting the right side’s
been affected, or both sides, suggesting a
bilateral disease. The trouble about bilateral
expansion being reduced is that it’s quite
difficult to detect, unless it’s very obvious.
Causes of unilateral reduction in expansion:
well, any disease that occurs on one side
of the chest is going to affect expansion
of that chest if it’s extensive enough.
A large pneumothorax, and even a small pneumothorax
probably would be detectable by careful clinical
examination. A severe pneumonia, a pleural
effusion, lung collapse, a previous surgery
to remove lobes or the whole lung itself and
again, destructive lesions of the lung, mesothelioma
and pleural thickening. They will all reduce
expansion on the affected side.
Bilateral diseases: well, by definition, you’re
talking about diseases that affect both lungs
equally. And that will be airways diseases
such as COPD and asthma, interstitial lung
diseases and bronchiectasis, depending on
the cause. Some causes of bronchiectasis are
unilateral, most are bilateral.