Let's take a look at obstructive lung diseases
and our first true pathology here, under obstructive,
we’ll take a look at asthma. Keep in mind
that much of this information in terms of
its pathogenesis comes from immunology. So
our strict focus here is going to be our patient,
how are they going to present, and then ultimately,
tie this in with the other obstructive diseases
in which often times may be confused with
emphysema and chronic bronchitis.
Let’s begin. Asthma, inflammatory disease,
small airway. Inflammation to airway, that
leads to what? Mucous production. Stop there.
I told you at some point in time that we will
take a look at the definition here versus
definition of chronic bronchitis. Why do I
bring chronic bronchitis into play? Because
of mucous production. Chronic bronchitis
however, represents the fact that your patient
is presenting with 3 months of continuous
productive cough over a 2 year span. Bronchospasm,
leading to a reversible obstructive
lung disease. Well, it depends. But for
the most part, think of it as being reversible.
Why? Well, if you’re able to relieve your
patient of whatever exposure that the patient
might be having resulting in the asthma type
attack, maybe perhaps you are able to reverse
it. That’s an important definition there.
Bronchodilators come to mind.
Usually and typically seen in young patients.
Many asthma patients usually end up having
or have had exposure to allergen. This puts
you in the realm of something like atopic
which is majority of your patients with asthma
or they’ve had a viral, URI stands for
upper respiratory tract infections. Now all
these can be exacerbated with having asthma.
Now, what’s going on here actually?
Well this comes under obstructive
so imagine that increased mucous production
taking place in the airway. Take a look
at the first picture up above. And if it is,
then you’re having a hard time then with
exhalation. Take a look at the bottom picture
here, the airways then filled with mucous.
So, in other words, it’s airway reactive
disease, isn’t it? Bronchospasms. Now, if
you want to keep these airways open then you
tell me as to what kind of receptor these
would then act upon or what kind of drug or
perhaps your adrenergic agents would act upon
in which it would then bring about bronchodilation?
Increased smooth muscle tone, narrowing
your airways is now a problem, increased inflammation, edema
further causes narrowing and may result in
plugs and these plugs make it difficult for
you to do what? Good, difficulty with exhalation.
How is the patient going to sound? Wheezing,
wheezing way down in the alveoli. Keep that
Asthma is an obstructive, expiratory disease
as noted, patients will have episodic wheezing,