Page 371 - Small Animal Internal Medicine, 6th Edition

CHAPTER 22 Disorders of the Pulmonary Parenchyma and Vasculature 343

actively infected patients, and face masks should be cleaned condition does not improve within 72 hours, it may be neces-
and disinfected. sary to alter treatment or perform additional tests. Animals
VetBooks.ir Physiotherapy that show improvement are sent home and are reevaluated
every 10 to 14 days. Once clinical and radiographic signs
Animals that are in a sufficiently stable condition and can
tional week.
tolerate the oxygen demands should be mildly exercised. have resolved, antibiotic treatment is continued for an addi-
Activity causes animals to take deeper breaths and to cough, A more objective way to determine adequate duration of
which promotes airway clearance. Animals that are recum- therapy may be possible through the monitoring of C-reactive
bent are turned every 2 hours. Lying in one position impairs protein (CRP). Eighteen dogs with bacterial pneumonia that
airway clearance, and lung consolidation can occur if one were treated for 5 to 7 days beyond the normalization of CRP
side remains dependent for prolonged periods. had a shorter total duration of antibiotic therapy (median 21
Physiotherapy is indicated after nebulization to promote days) compared with dogs treated for 3 to 6 weeks in total
coughing and facilitate the clearance of exudate from or 1 to 2 weeks beyond the resolution of alveolar densities
the lungs. Mild exercise is used when possible. Other- on radiographs (median 35 days) without an increase in
wise, coupage is performed. To perform coupage, the cli- relapses (Viitanen et al., 2017).
nician strikes the animal’s chest over the lung fields with Evidence of infection on initial radiographs can obscure
cupped hands. The action should be forceful but not that of focal disease processes such as neoplasia or foreign
painful and should be continued for 5 to 10 minutes if bodies, and focal opacities may not be apparent while an
tolerated by the patient. Coupage may also be beneficial animal is receiving antibiotics. Therefore radiographs should
for animals with lung consolidation that are not receiving be reevaluated approximately 1 week after antibiotic therapy
nebulization. has been discontinued in animals with recurrent infection or
suspected localized disease. Persistence of localized disease
Bronchodilators after long-term antibiotic therapy is an indication for com-
In cats, bronchospasm can occur secondary to inflamma- puted tomography and bronchoscopy, thoracoscopy, or
tion. Bronchodilators are used in cats that show increased thoracotomy.
respiratory efforts, particularly if expiratory wheezes are aus-
cultated. Bronchospasm is uncommon in dogs, but broncho- Prognosis
dilators (particularly theophylline) may have other potentially Bacterial pneumonia responds readily to appropriate therapy.
advantageous effects. If bronchodilators are administered, The prognosis is more guarded in animals with underlying
patient status should be monitored closely because broncho- problems that predispose them to infection, and the likeli-
̇ ̇
dilators may worsen ventilation/perfusion (V/Q) mismatch- hood of eliminating these problems must be taken into
ing, thereby exacerbating hypoxemia. They are discontinued consideration.
if clinical signs worsen or do not improve. Bronchodilators Pulmonary abscess formation is an uncommon compli-
are discussed in the sections on Canine Chronic Bronchitis cation of bacterial pneumonia. Abscesses are seen as focal
and Feline Bronchitis (Idiopathic) in Chapter 21. lesions on radiographs, and entire lobes may be involved.
Horizontal-beam radiographs can be useful in determin-
Other Treatment ing whether lesions are filled with fluid. Ultrasonography
Expectorants are of questionable value in dogs and cats. Ace- can also be helpful in characterizing areas of consolidation.
tylcysteine is a mucolytic agent that some clinicians believe Abscesses resolve in response to prolonged medical therapy
is beneficial for the treatment of dogs with severe bron- in some animals, but if improvement is not observed or
chopneumonia when administered intravenously. It is quite radiographic evidence of disease reappears after discon-
possible that the antioxidant effects of this drug, rather than tinuation of therapy, surgical excision (i.e., lobectomy) is
its mucolytic property, account for any benefit that may be indicated.
seen. Acetylcysteine should not be administered by nebuliza-
tion because of its irritant effects on the respiratory mucosa.
Glucocorticoids are relatively contraindicated in animals TOXOPLASMOSIS
with bacterial pneumonia. Oxygen therapy (see Chapter
25) is provided if clinical signs, arterial blood gas measure- The lungs are a common site of involvement in cats with
ments, or pulse oximetry measurements indicate the need toxoplasmosis. Thoracic radiographs typically show fluffy
for it. alveolar and interstitial opacities throughout the lungs
in such animals. Less often, a nodular interstitial, diffuse
Monitoring interstitial, or bronchial pattern, lung lobe consolidation, or
Dogs and cats with bacterial pneumonia should be closely pleural effusion is seen. Organisms are rarely recovered from
monitored for signs of deteriorating pulmonary function. the lungs by tracheal wash. Bronchoalveolar lavage is more
Respiratory rate and effort and mucous membrane color likely to retrieve organisms (see Fig. 20.17). Toxoplasmo-
are monitored at least twice daily. Thoracic radiographs and sis is a multisystemic disease and is discussed in detail in
the CBC are evaluated every 24 to 72 hours. If the animal’s Chapter 98.