Stephen J. Ettinger
Collapsing trachea occurs most often in middle-aged
to older dogs. The diagnosis is suggested by a honking cough
precipitated by activity, excitement, or water drinking. Non-productive
coughing may occur without a stimulus. Signs vary and include mild to
severe panting, respiratory distress, and bluish discoloration of the
mucous membranes (cyanosis). Abdominal breathing efforts result in tense
abdominal muscles.
Dogs are frequently overweight but may be thin. A
heart murmur associated with valvular heart disease is often encountered
because both problems occur in aging dogs.
Collapsing trachea results when the windpipe
(tracheal) cartilages soften. The trachea (windpipe) should resemble a
relatively firm garden hose. Viewed on end, the windpipe is a U-shaped
structure with a tight membrane covering the top. Where cartilage
softens, it collapses and widens at the top. The membrane then drapes
(collapses) loosely, blocking the inside of the "hose." This
results in an inability to bring air into or out of the trachea and
lungs during breathing.
Complications of this disease include lung problems,
heart disease and/or failure, enlarged liver, and chronic kidney
insufficiency. Dental infections, other infections, and obesity
aggravate the disease.
The diagnosis of collapsing trachea, initially
historical, is substantiated when a veterinarian can cause your pet to
cough by digital manipulation of the neck. Radiographs (x-rays) identify
changes in the trachea during both inspiration and expiration.
The diagnostic evaluation includes laboratory
sampling of the blood to identify causal or complicating medical
problems, motion studies of the trachea and lung during respiration,
endoscopic examination of the windpipe and throat, and evaluation of
abdominal organ enlargement.
There are four components of treating collapsing
trachea. During the acute phase, respiratory distress and severe bouts
of coughing are ameliorated with drugs that relax the trachea and lung
and sedate the pet. Fluid congestion is
relieved
with diuretic drugs, and short-term anti-inflammatory agents minimize
swelling and tissue irritation. Antibiotics are utilized if there is an
infection. Cough suppressants temporarily relieve discomfort. Cough
suppressants (narcotic derivatives) may be used in a lifelong schedule
for some pets with collapsing trachea.
Later, drugs that relieve bronchial constriction and
spasm are utilized along with products to reduce anxiety and
over-stimulation. Anticough medications are used orally as necessary.
Corticosteroid anti-inflammatory drugs may be helpful during episodes of
acute exacerbation of the coughing.
Problems requiring simultaneous medical care that
compromise the tracheal syndrome include recurrent pulmonary or
pharyngeal infections, dental disease, and swelling of lymph tissue in
the pharynx and tracheal region. Weight control is important.
Evaluation of thyroid function may be indicated.
Liver enlargement, secondary to fatty infiltration or other disease,
adversely affects the outcome of this disease. Many smaller dogs are
simultaneously affected with heart disease. You veterinarian understands
how these conditions interact. Diagnosing and treating both may
significantly improve the long-term prognosis.
Surgical correction of a collapsing trachea may be
considered in young dogs when the trachea is collapsed in the neck
region. Older dogs, those with complicating medical problems, and those
with most of the trachea affected are not candidates for surgery.
The prognosis remains good for many pets with
early-developing collapsing trachea, but the condition can be a serious,
life-threatening problem when severe coughing and respiratory distress
negatively affect a good prognosis. The client should be made aware of
the frustrating nature of therapy for these pets. Unless properly
informed that coughing is likely to continue to occur to some degree, on
and off, the client may become frustrated and seek additional care.
