Definition. Pathology, neurotic origin, bronchial spasms, swelling of
mucosa, fibrinous inflammation of bronchioles, Berkart’s
streptococcus, irritants formed in indigestion, overfeeding,
inactivity, plethora, constipation. Symptoms, obesity, sluggishness,
recurrent paroxysms of dyspnœa, hard cough, tense abdomen,
constipation, piles, depilation of skin, tartar covered teeth, fœtid
breath. Retching, vomiting, a glairy mucus, emaciation may follow.
Lesions, emphysema, fatty deposits in mediastinum, old standing
diseases of the heart, lungs and digestive organs. Treatment,
antispasmodics by lungs or rectum, stramonium, nitre fumes, emetic,
purgatives, vegetable diet, exercise, sedatives, blisters. Asthma in
the horse.
_Definition._—A neurotic affection mainly affecting the pneumogastric
nerve, and leading to paroxysms of stenosis or constriction of the
bronchioles and attacks of dyspnœa. In its initial stages it is
associated with corpulence and disordered digestion, and later with
congestion and swelling of the mucosa of the bronchioles, emphysema, and
dilatation of the right side of the heart.
_Pathology._ Asthma is generally attributed to spasm of the bronchial
muscles (Williams), and though recent observations have failed to
sustain this it must be admitted that in the majority of cases it is of
decided neurotic origin. Again it is attributed to erythematous swelling
in patches of the bronchial mucosa, (Clark). Another theory is that it
is a fibrinous inflammation of the mucosa of the bronchioles, the
tenacious exudate blocking the tubes more or less completely and relief
coming with a more diffluent secretion. Berkart found a streptococcus in
the sputa which he supposed to be the final cause. Again it has been
held to depend on the circulation in the blood of deleterious matters
introduced during digestion. Again it has been attributed to a neurosis
roused by constipation and the accumulation of irritant matters in the
intestine. Whatever local conditions may be operative, there can be no
doubt that in dogs it is almost exclusively confined to those kept
indoors, overfed, without exercise, plethoric and constipated. The
disease seems to originate in and persist by nervous disorder propagated
from the digestive organs. A change of diet or any disturbing cause may
bring on a paroxysm.
_Symptoms._ The disease is one of pet dogs, kept in towns, deprived of
exercise, fresh air, and of the opportunity to relieve the bowels at
will, and gorged with highly spiced meats, and sweets at least three
times a day. Sluggishness and obesity are marked characteristics of the
dog when first attacked though in the advanced stages the violence of
the paroxysms and their frequent recurrence may have induced extreme
emaciation.
The affection is usually ushered in by a cough, at first slight, but
soon becoming frequent, hard and sonorous, as in the early stages of
bronchitis. The cough becomes very troublesome and the breathing
habitually labored, but at irregular intervals a paroxysm comes on which
threatens death by suffocation. The dog stands or sits on his haunches
with open mouth, pendent tongue and staring eyeballs, panting for
breath, and has his condition aggravated by every change of position or
other source of excitement. By the frequency and severity of the attacks
may be estimated the danger of the patient.
An examination in the intervals of the attacks detects some disturbance
of the digestive organs. The tense and distended condition of the
abdomen usually manifests the existence of overloaded stomach and
bowels, of indigestion, tympany and constipation. Piles are often
present as a result of long continued costiveness. The skin is dry and
unthrifty, and often in patches denuded of hair. The teeth are covered
with tartar and the breath fœtid.
Retching is occasionally seen to occur during a violent access of
coughing, but only a little glairy mucus is brought up.
The cough, hurried breathing, and paroxysms of dyspnœa become
aggravated, the general health suffers largely, and death often ensues
in a state of great weakness and emaciation.
On _dissection_ of such cases the lesions of various old standing
diseases of the heart, lungs, or abdominal organs have been met with at
times, and such disorders have doubtless assisted in maintaining and
aggravating the asthma. The most constant lesions, however, are
emphysema of the lung, and accumulations of fat in the mediastinum.
=Treatment.= 1st. =During a paroxysm.= This is confined to the
administration of antispasmodics either by inhalation or as an injection
to avoid the additional suffering of swallowing. Ether or chloroform may
be inhaled from a sponge, but the employment of these should be guarded
especially in advanced cases when besides the prevailing weakness there
is reason to suspect structural changes in the heart. The same agents in
doses of one, two or three teaspoonfuls, or laudanum in double that
quantity may be thrown up as an enema, and may be combined with a couple
of ounces of castor oil when costiveness exists. The fumes from burning
stramonium or from burning brown paper which has been previously soaked
in a strong solution of nitrate of potass, will in many cases suddenly
cut short the paroxysm. If on the other hand there is reason to believe
that the stomach is overloaded the attacks will often be suddenly cut
short by giving an emetic. For this purpose a grain of tartar emetic may
be shaken upon the tongue, or a dessert spoonful of wine of ipecacuan,
or of antimony, poured over the throat. 2d. =In the intervals between
the paroxysms.= Attention must be given to counteract any inflammatory
action in the chest by which the disease may be maintained. Our chief
object, however, must be to divest the animal of its superfluous fat and
bring the digestive organs into a healthy condition. Unfortunately the
propensity to fatten in some dogs seems to be a morbid condition. The
food appears to be stored up as fat at the expense of muscular and other
tissues even when the animal is kept on the borders of starvation. All
flesh must be withheld and coarse vegetable fare alone allowed. A well
boiled pudding (porridge) made with oatmeal or Indian corn meal, water
and a little salt, with a small quantity of skimmed milk or buttermilk,
is an excellent diet in such cases. The amount must be small, though the
hitherto pampered favorite will rarely seek to fully replenish his
stomach until he has forgotten his former extravagant habits.
A good deal of open air exercise must be given, not violent, but gentle
and long continued, and this though the patient may appear physically
unfit for it. Exercise should be given three hours or more after a full
meal. Purgatives (one ounce castor oil) should be administered twice a
week. A clean bed, not too soft nor luxurious, should be allowed in a
dry, airy place. The skin should be well brushed daily and occasionally
washed thoroughly with soap, care being taken to dry the coat completely
afterwards. Sedatives should be given daily, such as a half grain each
of stramonium and tartar emetic, and in advanced stages with weakness
and emaciation vegetable tonics will be demanded.
Blaine strongly advocates a course of emetics, given every alternate
day, and Mayhew lauds frequently repeated ammoniacal blisters to the
sides. Such measures will be especially applicable when there is
irritation and discharge from the bronchial mucous membrane. Strong
subjects can alone, however, bear such treatment.
All cases of asthma in the dog are obstinate and critical and require
much judgment in treatment.