Tracheobronchial diseases--dogs Flashcards Preview

• Radiographs--may see tracheal mass
• Bronchoscopy--masses are found
• Tracheal/bronchial brushes or biopsies
• Fecal

Oslerus osleri

• Fenbendazole
• Ivermectin

• Signalment
  • Middle aged to older dogs (rarely cats--full cartilagenous rings in trachea)
  • Toy or small breed dogs--usually obese
• Usually acquired reduction in chondrocytes
  • Lack glycosaminoglycans and chondroitin sulfate in tracheal cartilage
• Pathophysiology
  • Weak cartilage w/ flattening of tracheal rings, resulting in mechanical irritation, edema, and inflammation
  • Tracheal rings lose their firmness and collapse

• Goose honking cough
• Exacerbated by exercise, excitement and eating
• Elicited w/ tracheal palpation
• Causes cyanosis and collase/syncope
• Many dogs have hepatomegaly
  • Theory: O2 deprivation--> significant liver disease 
• Many have cardiac murmur
• Variable breath sounds

• Signalment, history, clinical signs
• Thoracic/cervical rads
  • Inspiratory AND expiratory films
  • May/may not be diagnostic
  • Often underestimate severity
  • Extra-thoracic and intra-thoracic collapse occurs
• Fluoroscopy
• Bronchoscopy
  • Best diagnostic tool
  • Assess dynamic change
  • Grade extent of collapse
  • Look for concurrent diseases

• Sedation often required
  • Acepromazine, butorphanol, diazepam
• O2-rich environment
  • O2 cage, nasal catheterization
• Use cough suppressant (antitussive)
  • Butorphanol injectable/oral
  • Oral hydrocodone
• Corticosteroid
  • Single dose for anti-inflammatory effects
  • 0.1mg/kg IV dexamethasone
• Intubation may be required

• Weight loss
• Avoid neck collars
• Avoid excitement
  • Use sedative if required
  • Behavioral--reward quiet behavior
• Avoid dust, smoke, pollens, carpet powders, etc.
• Use cough suuppressants--butorphanol, codeine, hydrocodone
• Use corticosteroids--very short course if required
  • Too long--> suppress immune system--> secondary bac. pneumonia
• Antibiotics for secondary infection if suspected

• 30% of dogs do not respond to medical management
• Surgical intervention--referral
  • Extraluminal stents
    • For extrathoracic or cervical collapse
  • Endoluminal stents
    • For intrathoracic or entire tracheal collapse
    • Nitinol stents are used

• Inflammation of bronchial walls--> thickened walls, increased mucous --> obstruction of small airways
  • Chronic obstructive pulmonary disease
• Clinical signs--daily cough > 2mo
• By the time it is diagnosed there is rarely a cause found for the underlying inflammation
  • Etiology is rarely determined
• Long term sequelae--emphysema, bronchiectasis, pneumonia
• Not similar to asthma in cats or people

• Signalment: small breeds, usually >6yrs
  • Often obese
• Client compliant: chronic cough, audible wheezes, exercise intolerance
  • Usually BAR, signs wax and wane
• Clinical signs--expiratory wheezes, crackles audible on inspiration and expiration
  • Dog can also have concurrent tracheal collapse or mitral valve insufficiency
• Diagnostics--exclude other causes of a cough
  • Rads, bronchoscopy, bronchial cytology and culture

• Eliminate triggers--smoke, excitement, allergens
• Keep hydrated--to aid mucociliary clearance
• Reduce weight if obese
• Prednisolone--reduce inflammation
• Bronchodilators--only in reversible stages, use only w/ corticosteroids
• Antibiotics--if secondary bac. infection found
• Avoid cough suppressants--unless a tracheal collapse is present or the cough is inconsistent and dry
• Metered dose inhalers (MDI)--inhalation steroids
•  

• Secondary to chronic conditions like chronic bronchitis
• Pathophysiology
  • Damage to bronchial structure--> thickened wall, dilation of structure
  • Mucous cannot be cleared--> builds up 
  • Secondary infection --> recurrent bronchopneumonia --> more damage to airways
  • Dilation of bronchial tree is irreversible caused by the destruction of the muscle and elastic tissue