Newsgroups: sci.med
Subject: Re: Chronic Bronchitis & Asthma
From: km@ky3b.pgh.pa.us (Ken Mitchum)
Date: 2 Jan 93 16:06:55 GMT
Organization: KY3B - Vax Pittsburgh, PA

In article <1992Dec17.094320.11147@visual.spk.wa.us>, pwageman@visual.spk.wa.us (Peggy Wageman) writes:
|> Are the symptoms of chronic bronchitis and asthma the same?  And if they are
|> how are they diagnosed?  Are the medication the same for both?  Any information
|> is appreciated.  Thanks,  Peggy Wageman

This is a commonly asked question which is impossible to answer fully without going
into great medical detail. So my answer will be relatively brief and not very detailed,
which may upset some people.

Chronic bronchitis and emphysema are two different forms of "chronic obstructive pulmonary
disease", or COPD. These diseases are commonly associated with cigarette smoking, although
there are other causes. To adequately describe the differences between them would require
a discussion of lung anatomy and physiology that is way beyond what would be appropriate
on the net. Basically, with chronic bronchitis, there is much sputum production, while
with emphysema, actual destruction of lung predominates. The "typical" patient with
chronic bronchitis is the "blue bloater", who is hypoxic without being short of breath,
and is subject to CO2 retention when given supplemental oxygen. The "typical" patient
with emphysema is more the "pink puffer" who is always short of breath, even when
maintaining decent oxygenation. Many patients have features of both conditions, and
we usually just refer to a patient as having "COPD." 

Patients with COPD often may have bronchospasm, which results in wheezing and an
acute increase in shortness of breath. Bronchospasm is also the physiologic mechanism
of asthma. So the brief answer to your question is yes, the symptoms of bronchospam
are the same for chronic bronchitis and asthma. However, the disease process is quite
different: a patient with COPD has a chronic, slowly worsening disease process,
which can be demonstrated through pulmonary function studies even when there
is no acute bronchospasm. This is not in general true of the patient with asthma,
who basically has normal lungs in between attacks. Another way of saying this is
to describe asthma as "reversable airways obstruction" and COPD as "fixed obstruction",
which describes the response to bronchodilator medication given in a
pulmonary function study.

In the real world, patients often have features which are combinations of both
conditions, for example, a patient with chronic bronchitis who has intermittant
bronchospasm that responds quite well to medication. Some people use the term
"asthmatic bronchitis", which I personally do not like at all. 

Some of the medications used for the two conditions are the same, although the
emphasis is quite different. Theophylline drugs are commonly used as mild bronchodilators,
although most pulmonary doctors will tell you they are not very potent medications,
and often they do not result in any improvement in PFTs, even though the patient
often feels less short of breath with these drugs. Inhaled bronchodilators are the
real mainstay of treatment. With asthma, the emphasis is on beta-adrenergic
stimulants, such as albuterol. With COPD, the emphasis is on anticholinergics,
such as ipatroprium. Many COPD patients respond poorly to just about everything,
and unfortunately, end up on just about everything. In such cases, the doctor is
usually afraid to stop anything, less make the patient worse.

-km