Tracheobronchial diseases--dogs Flashcards
(31 cards)
1
Q
What signs are associated with disease in the following areas:
Larynx (voicebox)?
Trachea (windpipe)?
Bronchi?
A
- Larynx = hoarse bark, gagging, inspiratory difficulty
- Trachea = cough and resp distress
- Bronchi = cough and resp distress
2
Q
Clinical signs?
A
- Cough (most common)
- +/- productive
- Retch/gag
- Wheezing
- Inspiratory sounds
- Tachypnea
- Resp distress
- Cyanosis if severe
3
Q
Canine etiology
A
- Brachycephalic airway syndrome and laryngeal paralysis–know hallmarks
- Canine infectious respiratory disease complex: kennel cough
- Canine influenze
- Oslerus osleri
- Collapsing trachea, bronchi
- Canine chronic bronchitis
- Bronchiectasis
4
Q
Canine infectious respiratory disease complex (CIRD): kennel cough
Pathogens responsible?
A
- Parainfluenza virus–mild clinical signs
- Canine adenovirus (CAV-2)
- Mycoplasma spp.–mild to severe clinical signs
-
Bordetella spp.–mild to severe clinical signs
- Attaches to cilia of bronchial epithelium and interferes with motility–resulting in mucous accumulation and inflammation
- Other viruses–canine distemper virus (CDV), canine respiratory coronavirus (CRCoV), canine herpes virus (CHV-1), and canine influenza virus (CIV)
- Secondary bac. invaders are comon
5
Q
CIRD: kennel cough
Contagious?
Spread?
Incubation?
Most common clinical sign?
A
- Very contagious–acquire pathogen from dog shows, kennels, vet clinics, etc.
- Spread through resp secretions and fomites
- Incubation 3-7 days
- Coughing is most common clinical sign
6
Q
CIRD: kennel cough
Clinical signs
A
- Usually develop 4-10 days post exposure
- Uncomplicated
- Non-sick animals
- Involves upper airways
- Dry cough is elicited on tracheal palpation
- Serous oculonasal discharge, gagging, and retching can be found
- Complicated
- Sick animals
- Upper and lower airways
- Moist cough
- Oculonasal discharge more mucopurulent
- May develop into bronchopneumonia
7
Q
CIRD: kennel cough
Diagnosis
A
- History
- Where has the dog been? Kennels?
- Has the dog received bordetella vaccine recently?
- Clinical signs
- In uncomplicated cases further diagnostics may be included
- Hemogram–left shift neutrophilia
- Thoracic radiographs
- Transtracheal wash, cytology and culture
- PCR panels for upper resp viruses and bac.
8
Q
CIRD: kennel cough
Treatment: uncomplicated
A
- Uncomplicated
- Restricted exercise
- Use doxycycline if Bordetella spp is suspected
- Usually resolves w/in 2 weeks
- Cough suppressants
- Butorphanol, hydrocodone, codeine derivative, dextromethorphan
9
Q
CIRD: kennel cough
Treatment: complicated
A
- Restrict exercise
- Systemic antibiotic for 2 wks
- Doxycycline, tetracycline, sulphonamides, enrofloxacin
- Penicillins are not a good choice for Bordetella spp as they reach poor concentrations in the respiratory secretions
- Nebulization w/ or w/o gentamycin (only antibiotic that can actually have an effect when added to nebulizer)
- Cough suppressants (avoid if bac. pneumonia is present)
- Bronchodilators
- Albuterol, theophylline (avoid or reduce dose by 30% if using together w/ fluoroquinolones)
10
Q
CIRD: kennel cough
Prognosis?
Prevention?
A
- Prognosis = good to excellent
- Prevention
- Avoid places where dog could get infected
- Vaccination
- Sanitation–household bleach dilated 1:32
- Ventilation in kennels
11
Q
CIRD: kennel cough
Vaccination
A
- Parenteral vaccination
- CAV-2, CPIV, CDV and Bordetella spp (dogs)
- Blocked by maternal antibodies so repeat every 3-4wks until 16wks of age
- Intranasal vaccination
- Bordetella spp and CPIV
- Important for high- or at-risk animals
- New vaccinations against CIV
- Need vaccine 2-3 wks BEFORE going to kennels for protection
12
Q
Canine influenza
Influenza type A?
Spread?
A
- Type A
- H3N8 (related to equine flu)
- H3N2 (related to avian flu)
- Spread through direct contact (resp secretions) and fomites or indirect contact through kennel surfaces, water/food bowls, toys, collars and leashes
13
Q
Canine influenza
Clinical signs
Diagnosis
A
- Clinical signs
- 2-5 days post exposure
- Usually results in coughing, sneezing, nasal discharge and fever; may result in hemorrhagic pneumonia
- Disease has high morbidity but low mortality
- 20% don’t show clinical signs and just shed virus
- Most animals dev. mild clinical signs, but some can dev. severe (2 forms)
- Diagnosis–PCR, serology (acute and convalescent titres) or viral isolation
14
Q
Canine influenza
2 forms?
A
- Mild/uncomplicated–typical mild uncomplicated kennel cough
- Severe/complicated
- Pyrexia (104-106F)
- Hemorrhagic pneumonia–dyspnea, tacypnea, hemoptysis
- Rapid onset and animal can die w/in hours
- 5-8% mortality
15
Q
Canine influenza
Treatment
Prevention
A
- Treatment
- Supportive care, NSAIDs to reduce fever, and IV fluids
- Systemic antibiotics in the severe form–may require ICU but extremely contagious and requires isolation
- Prevention
- Vaccination
- Isolate sick and exposed dogs
- Change clothes/wash hands
- Virus does not persist in environment >48hrs–good quality bleach/disinfectant solution
16
Q
Oslerus osleri
What is it?
Generally affects?
Life cycle?
Causes what?
Clinical signs?
A
- Canine parasite on resp. passages
- Generally affects younger dogs in kennels
- Direct life cycle–larvae ingested, molt in small bowel and migrate to lungs, bronchi, and trachea
- Cause cream-colored nodules in trachea
- Clinical signs: coughing, wheezing, dyspnea
17
Q
Oslerus osleri
Diagnosis
A
- Radiographs–may see tracheal mass
- Bronchoscopy–masses are found
- Tracheal/bronchial brushes or biopsies
- Fecal
18
Q
What parasite is this indicative of (white plaques)?
A
Oslerus osleri
19
Q
Oslerus osleri
Treatment
A
- Fenbendazole
- Ivermectin
20
Q
Tracheal collapse
Signalment?
Usually acquired reduction in what?
Pathophysiology?
A
- 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
21
Q
Tracheal collapse
Clinical signs
A
- 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
22
Q
Tracheal collapse
Diagnosis
A
- 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
23
Q
Tracheal collapse
Grading scale?
A
24
Q
Tracheal collapse
Treatment: calm patient (/owner)
A
- 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
25
**Tracheal collapse**
Treatment: break the cycle
* 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
26
**Tracheal collapse**
Response to medical management?
Surgery?
* 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
27
**Canine chronic bronchitis**
What is it?
Clinical signs?
Cause?
Long-term sequelae?
Not similar to what?
* 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**
28
**Canine chronic bronchitis**
Signalment
Client complaint
Clinical signs
Diagnostics
* 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
29
**Canine chronic bronchitis**
Treatment
* 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
*
30
**Bronchiectasis**
Secondary to?
Pathophysiology?
* 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
31
What specific diseases in the various lung lobes can cause bronchiectasis?
* Upper lung lobe
* Cystic fibrosis
* Tuberculosis
* Central
* Cystic fibrosis
* ABPA
* Congenital tracheobronchomegaly
* Lower
* Childhood infection
* Aspirations
* Immunodeficiencies
