Page 1972 - Cote clinical veterinary advisor dogs and cats 4th

986 Tracheal Avulsion

○ Clinical improvement is not likely in Prevention • Do not eat undercooked meat or unpasteur-
severe cases of neosporosis with muscle • Do not allow dogs or cats to hunt or eat • Boil or filter drinking water from unreliable
ized dairy products.
VetBooks.ir • In milder systemic cases, clinical signs of • Clean litter boxes daily (oocysts need 1-5 • Pregnant women must avoid contact with
uncooked meats.
contracture.
sources.
systemic illness usually begin to resolve in
days to sporulate and become infective).
1-2 days after institution of therapy.
oocysts.
• Uveitis should resolve in 1 week with • Disinfect litter boxes with boiling water at soil, cat litter, raw meat, and cats excreting
least once weekly.
therapy. • Cover outdoor sandboxes to keep feral cats • Produce should always be washed thoroughly
• Neuromuscular deficits should partially out. or cooked because it is now known that
resolve within 2 weeks of initiation of • Immune-suppressed or pregnant cat owners people are commonly exposed to T. gondii
therapy; however, in most puppies with should have someone else clean the feline litter sporulated oocysts in this way.
neosporosis, some signs may be permanent. box or clean it daily while wearing gloves. • Although T. gondii has been potentially
• Older puppies (>16 weeks) and adult dogs • Do not allow dogs to defecate in food animal linked to a number of human behavioral
generally respond better to treatment for N. or dairy operations. abnormalities, the associations are weak, and
caninum. owners usually do not acquire toxoplasmosis
Technician Tips from their cats.
PEARLS & CONSIDERATIONS Risk of infection to veterinary staff is minimal
to nonexistent with appropriate handling, such SUGGESTED READING
Comments as keeping feline feces refrigerated until handled, Dubey JP, et al: Toxoplasmosis and neosporosis. In
• Patients with suspected neosporosis or wearing gloves, and hand washing. Greene CE, editor: Infectious diseases of the dog
toxoplasmosis should respond to appropriate and cat, St. Louis, 2012, Elsevier, pp 806-827.
therapy within several days. If the patient is Client Education AUTHOR: Michael R. Lappin, DVM, PhD, DACVIM
not responding or progressing, there may be • Wash hands and surfaces after handling raw EDITOR: Joseph Taboada, DVM, DACVIM
concurrent disorders. meat or cleaning litter boxes.
• No drug clears either organism from the • Wear gloves when gardening, and wash
tissues of dogs or cats, and relapses may vegetables and hands thoroughly to prevent
occur. contamination from soil.

Tracheal Avulsion Client Education
Sheet

BASIC INFORMATION • Intermittent, continuous, or progressive • Initial dyspnea may persist, worsen, or resolve
respiratory distress until subsequent stenosis or displacement
Definition • Chronic onset of dyspnea and exercise causes return of clinical signs.
Disruption in the continuity of or a tear in intolerance days to weeks after traumatic
the trachea event DIAGNOSIS
Synonyms PHYSICAL EXAM FINDINGS Diagnostic Overview
Tracheal laceration, tracheal rupture, tracheal • Increased respiratory effort: decreased heart Tracheal avulsion is suggested by a history of
transection and breath sounds if pneumothorax cervical trauma or recent anesthesia, especially
• Subcutaneous emphysema (inflated, crepitant in the presence of subcutaneous emphysema,
Epidemiology subcutaneous space) pneumomediastinum, or obvious radiographic
SPECIES, AGE, SEX • Precipitation of severe dyspnea with neck disruption of the trachea. These patients typi-
Reported primarily in small dogs and cats; no flexion cally present 2-3 weeks after the initial injury
age or sex predisposition • Severity of signs depends on severity of tear with signs of airway obstruction.

RISK FACTORS Etiology and Pathophysiology Differential Diagnosis
• Choke chains • Direct injury to the trachea due to blunt or • Tracheal foreign body
• Overinflation of endotracheal tube cuff penetrating trauma to the cervical or thoracic • Collapsing trachea
• Traumatic intubation area (e.g., bite wounds, hit-by-car) • Tracheal stenosis
• Cervical trauma • Violent hyperextension of the head and neck • Tracheal neoplasia or mass
• Thoracic trauma can stretch the trachea and cause tracheal • Laryngeal paralysis
transection. • Laryngeal collapse
ASSOCIATED DISORDERS ○ The carina and lungs are a fixed point • Tracheobronchitis
• Pneumomediastinum that is stronger than the tracheal wall. • Pneumothorax/pneumomediastinum from
• Pneumothorax ○ As the trachea is stretched, the intratho- other causes
• Subcutaneous emphysema racic trachea ruptures cranial (1-4 cm) to • Pulmonary disease
• Musculoskeletal injury consistent with the carina.
trauma (cervical/thoracic) • The dorsal tracheal membrane is the most Initial Database
common site of tear from overinflation of • Results of CBC, serum biochemistry panel,
Clinical Presentation an endotracheal tube cuff (cats > dogs). and urinalysis are usually unremarkable.
HISTORY, CHIEF COMPLAINT • Peritracheal tissues (adventitia or media- • Cervical radiographs (lateral view) may show
• History of blunt or penetrating trauma or recent stinum) can maintain tracheal continuity discontinuity of the tracheal wall. Site of
general anesthesia and subsequent dyspnea (psuedotrachea). rupture may be obscured by the humeri or

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