Respiratory Flashcards
Advantage of BAL over tracheal wash
More sensitive
Difference between endotracheal wash and transtracheal wash
Transtracheal wash - through trachea done conscious
Endotracheal wash - under GA down ET tube
indications for bronchoscopy
Need samples
Airway assessment/treatment
Unexplained clinical signs
BAL types
Bronchoscopic - pre-oxygenate, sterile saline via catheter
Non-bronchoscopic - urinary catheter down ET tube, lung of interest positioned downwards
What is BAL useful for
Bronchopneumonia
Eosinophilic bronchopneumonia
Parasites
Chronic bronchitis
What is transtracheal wash useful for
Bronchopneumonia
Chronic bronchitis
Parasites
What occurs with chronic airway disease
Thickening of airways
Distortion
Mucous
Thinning of walls
What does oslerus osleri causr
Nodules in the trachea
Areas to look at for sneezing and nasal discharge
Facial symmetry
Eyes
Air flow
Lymph nodes
Nasal planum pigmentation
Teeth
Pain
Diagnostics for sneezing/nasal discharge
History
CS
Imaging
Rhinoscopy
Cytology
Serology
Nasal flush
How does aspergillosis present in dogs
Medium/long nosed breeds
Marked destruction of turbinates
Mucopurulent discharge with intermittent epistaxis
Pain on palpation
Sneezing
Deformity
How does nasal planum neoplasia present
Carcinoma - squamous cell, mets rare
White cats
Photodynamic therapy/planectomy to treat
Nasal cavity neoplasia
Normally malignant
Carcinomas in dogs
What is a cough
Reflex due to airway irritation, glottis closes, intrathoracic pressure increases, glottis opens to expel air quickly
Aetiology canine chronic bronchitis
Tracheal collapse
Chronic barking
FB
Previous infection/inhaled toxins
Environmental
Differentials for acute cough
Tracheobronchitis
Irritation
Fb
Pulmonary haemorrhage
Acute pneumonia
Acute oedema
Airway trauma
Differentials for chronic cough
Chronic bronchitis
Oslerus/aelurostrongylus
Tracheal collapse
Fb
Bronchopneumonia
Pulmonary neoplasia
Extra-luminal mass
Eosinophilic disease
Infectious tracheobronchitis causes
Canine parainfluenza
Canine adenovirus
Bordetella bronchiseptica
Anti-tussives
Don’t use unless absolutely necessary as normally protective
Butorphanol/codeine
Canine chronic bronchitis
Neutrophilic/eosinophilic infiltration of mucosa
Thickening of smooth muscle, fibrosis/scarring of lamina propria
Oxidative injury and inflammatory cells damage
Loss of ciliated epithelium
Signalment for canine chronic bronchitis
Small/toy breeds more common
Worse with excitement
Harsh cough
Externally well but often obese
What does bronchi-ectatic mean
Dilated airways
Shows as bronchial donuts
What do BAL results for canine chronic bronchitis typically show
Increased mucous
Non-regenerative neutrophils, eosinophils, macrophages
Cushman’s spiral - airway mucus casts
Management of chronic bronchitis
Weight control
Harness walks
Avoid irritants or smoking
Avoid dry environments
Oral/inhaled Glucocorticoids
Bronchodilators
Courage
Antimicrobials with need
Treatments for lower airway disease
Inhaled medications - corticosteroids, bronchodilators, nebulizers delivered by mask, spacing device, metered dose inhaler
Expensive, time consuming, owner compliance, patient compliance
What is salbutamol
Beta 2 agonists
Fast onset, lasts 3 hours
Cleared renally
10-20% reaches lower airways
SE - tachycardia, arrhythmias, tremors
Inhaled Corticosteroids
Fluticasone propionate
Slowly absorbed from lungs but dwells
Rapid liver metabolism
Long half life
Bronchodilatory and anti-inflammatories
Benefits of bronchodilators
Reduction in lower airway spasm
Decreases tendency for airway collapse improves muco-ciliary clearance
Inhibits mast cell degranulation
Oral therapy for bronchitis
Anti-inflammatories
Bronchodilators
Antibiotics, anthelmintics
Mucolytics
Feline bronchial disease
Feline asthma
Type 1 hypersensitivity
Suspected breed disposition eg Siamese
Smoke/feathers/inhaled dust
Can lead to chronic bronchitis
Common pathogens causing bacterial bronchopneumonia
E.coli
Klebsiella
Pasteurella
Staphs
Streps
Mycoplasma
Bronchiseptica
Is primary bacterial bronchopneumonia common
No it’s rare, look for the underlying cause
What does S.equi zooepidemicus cause in dogs
Fatal haemorrhagic pneumonia
Highly contagious, sudden onset
CS - pyrexia, dyspnoea, haemorrhagic nasal discharge, haemoptysis
Predisposing factors to bronchopneumonia
Debilitation
Prolonged recumbency
Immunosuppression
Immunodeficiency
Defective respiratory defenses
Damaged epithelium
Aspiration
Airway obstruction
Systemic sepsis
Bronchiectasis
Diagnosis of bacterial bronchopneumonia
CBC, biochemistry, UA, faecal
Thoracic radiography- early disease can show interstitial pattern only
Airway sampling - culture and cytology on fluid
Treatment of bacterial bronchopneumonia
Antibiotics
Supplemental humidified oxygen
IVFT
Anti inflammatories
Bronchodilators
Mucolytics
Physiotherapy
Nebulization
Surgery
What is the first thing you should do with respiratory noise
Localise it
What should you approach in the consult
Critical assessment of patient - emergency?
Condition
Breathing - rate, pattern, regularity, depth, effort
MM colour - pale, cyanotic, normal
Behaviours worrying the owner
Which breathing phase is longer
Inspiratory
What is orthopnoea
Dyspnoea in any position other than standing/erect sitting
What is trepopnoea
Dyspnoea only on one lateral - unilateral lung/pleural disease
What are the two types of alveolar cell
Type 1 - very thin squamous cell lining 95% alveolar surface
Type 2 - cuboidal cell secreting surfactant
What are the 4 areas that cause breathing difficulty
URT - inspiratory difficulty, noise, normally surgical, emergency tracheostomy
Pleural space - muffled heart/lung sounds, thoracic ultrasound, remove
fluid
Lung itself - stuff in alveoli of interstitium
Non-crs - metabolic/physiologic, rapid shallow breathing, severe difficulty
Clinical signs of cat flu
Wheezing
Coughing
Nasal discharge
Spotty tongue
Ocular discharge/discolouration
What is special about FHV-1 (herpes)
Sheds intermittently and without disease for life but exacerbated by stress
What type of virus is calicivirus
RNA related to norovirus
Key points about calicivirus
Shed by >80% cats in multi cat
Spontaneous outbreaks of severe disease
Tongue ulcers
Floppy kittens with synovitis
How do you treat Chlamydia feliz
Doxycycline 10mg/kg daily for 4 weeks
Presents with swollen conjunctiva
Difficulties of chronic rhinitis in cays
Have snuffles so don’t re-home well
Antibiotics can have to be prolonged
Long time decongestants
Specific antivirals
What is FCGS
Feline chronic gingivitis stomatitis
Associated with FCV
Full mouth extraction
Antibacterials
Diagnosing feline respiratory tract disease
Only when management will change
Oral/ocular swabs
Viral transport medium
PCR
Treatment for feline respiratory disease
Supportive care - nutritional, fluids, anti-inflammatories, nebulizers, eye drops,
Specific - antivirals
Prevention/control of feline respiratory disease
Hygiene, ventilation
Disinfection
Low stress
Vaccination
What is CIRD
Canine infectious respiratory disease
Clinical signs of kennel cough
Hacking cough
Submandibular lymphadenopathy
Ocular/nasal discharge
Lethargy
Pyrexia
What is canine adenovirus-2
Non enveloped DNA
Closely related to CAV-1
Vaccine based on CAV-2 for core
What is canine parainfluenza virus
Enveloped RNA virus
Upper URT only
Subcutaneous and intranasal vaccines
Pathogenesis of CIRD
Disrupts muco-ciliary escalator allowing bacterial invasion
What is canine coronavirus
Enveloped RNA
Not the same as enteric coronavirus
What is bordetella bronchiseptica
Primary/secondary disease
Mild - severe
Shedding 12 weeks post infection
What is canine distemper virus
Enveloped RNA, she’d in all body fluids
CS - bronchopneumonia, purulent ocular and nasal discharge, haemorrhagic vomiting and diarrhoea, neurological signs
Can strep equi effect dogs
Yes
Causes pyrexia, bloody nasal discharge and haematemesis
Prevention of canine respiratory disease
Hygiene
limit dog to dog contact
Ventilation
Vaccination
Clinical signs of infectious respiratory disease
Nasal dist
Ocular swelling/discharge
Coughing
Dyspnoea/tachypnoea
Stertor/stridor
Pyrexia
Depression
Lethargy
Inappetence
Treatment for canine respiratory disease
Symptomatic
- avoid choke chains
- clean eyes/nose
-nsaids
- anti-tussives (butorphanol/codeine/
Antibiotics - rarely necessary as viral - if used for secondary pathogens - tetracyclines, potentiated sulphonamides
Canine influenza
Cough/ purulent discharge
10-30 day duration
20% very unwell with pyrexia/pneumonia
~8% die
Vaccines in US
Serological evidence in foxhounds
How do bronchial foreign bodies present
Sudden onset coughing/gagging
Diagnostics for bronchial foreign bodies
Thoracic radiographs -can see pleural involvement but often difficult
Bronchoscopy - visualisation and retrieval look in all lobes
Primary pulmonary tumours
> 50% are solitary and often caudal right love - lobectomy
Present with non productive cough and exercise intolerance
What family are most lungworms from
Metastrongyloides
(Inc. oslerus osleri, filaroides, crenosoma vulpis, aelurostrongylus abstrusus, angiostongylus vasorum)
Oslerus osleri
10-18week PPP
Immune response to adult in trachea and bronchus
Dry rasping cough, exercise associated
6-12 month dogs most common
Bronchoscopy best diagnosis, L1 in faeces possible but variable
Fenbendazole treatment
Filaroides hirthi
Treat as oslerus osleri
Diffuse broncho-interstitial pattern
Crenosoma vulpis
Fox lung parasite can affect dogs
PPP 3 days
Indirect life cycles with slugs/snails
Adults in bronchi/bronchioles
Investigate and treat as oslerus osleri
Thoracic FNA
Ultrasound guidance
Lesions >1cm
Contraindicated by coagulopathy, pneumothorax, infectious process, pulmonary hypertension
Complications - pneumothorax, empyema, bleeding, implantation, seeding neoplasia
What causes stertor
Reverberation of the nasopharynx
Stages of laryngeal collapse
Stage 1 - laryngeal saccule eversion
Stage 2 - medial deviation of the cuneiform cartilage and aryepiglottic fold/aryepiglottic collapse
Stage 3 - medial deviation of corniculate process of arytenoid cartilage/corniculate collapse
aetiology of laryngeal collapse
neurogenic atrophy of laryngeal muscles
dysfunction of recurrent laryngeal nerves
generalised neuropathy
CNS origin
hypothyroidism
clinical signs of laryngeal dysfunction
stridor
cough
dyspnoea
change in phonation
exercise intolerance
collapse
signs related to severity of disease
CS worse when hot or exercised
diagnosis of laryngeal collapse
characteristic signs - auscultation of larynx/thorax
laryngoscopy - swallowing level
laryngoscope
inflated radiographs
haematology/biochemistry
emergency management for laryngeal collapse
rest
supplemental oxygen
sedation
iv access
corticosteroid
anaesthesia
tracheal collapse signs
goose honk cough
pulling on collar/lead
exercise
things that make the dog cough
latero-lateral flattened trachea
medical management of tracheal collapse
antitussives
bronchodilators
antibiotics
nsaids
inhaled corticosteroids/bronchodilaters
surgery for tracheal collapse
open ring procedure
stenting (must contact whole tracheal wall)
fungal rhinitis cause
Aspergillus fumigatus
CS of aspergillus
mucopurulent nasal discharge progressing to bilateral
intermitted epistaxis
ulceration/depigmentation of nasal planum
pain on palpation
sneezing
diagnosis of aspergillosis
history
clinical signs
blood tests - coagulopathy
diagnostic imaging - radiography of nose/sinuses, CT/MRI
rhinoscopy
cytology
serology
treatment for aspergillosis
challenging
prolonged oral anti-fungal ‘azoles’
topical therapy - enilconazole, clotrimazole best delivery by catheter into frontal sinuses
feline chronic rhinitis
common cause of nasal discharge
inflammation of the chonchae
increased mucous production
can be mild or severe
endoscopically similar to dogs
surgery for stenotic nares
wedge resection
alar fold resection
surgeries of the soft palate
partial staphylectomy
folded flap palatoplasty - thins and pulls forward to shorten palate
tonsilectomy - often included in soft palate surgery
arytenoid lateralisation surgery
tie back
prevent dynamic collapse of arytenoid cartilages - normally unilateral
post op care for laryngeal tie back
observe feeding/drinking
rest 2-3 weeks
antibiotics
analgesia
harness not collar
complications of laryngeal tie back
seroma formation
aspiration pneumonia
inadequate lateralisation
failure
change in bark
Signalment for lower airway disease in cats
Older - hyperthyroidism, neoplasia, cardiac disease
Younger - infectious causes
History for lower airway disease in cats
Age at presentation
Presentation - acute, episodic, chronic
Feline asthma
Reversible
Inhaled allergen
Airway hyper reactivity
Bronchoconstriction
Eosinophilic airway inflammation
Signs - episodic respiratory distress, dyspnoea, coughing
Chronic bronchitis
Response to infection/inhaled irritants
Airway damage
Excess mucous
Neutrophilic airway inflammation
Coughing
Pathogenesis of lower airway disease in cats
Hyperreactivity of bronchial smooth muscle - type 1 hypersensitivity, autonomic imbalance, muco-ciliary imbalance
Acute bronchoconstriction in response to triggers
Inflammation of bronchial mucosal lining
Can develop pneumothorax or spontaneous rib fracture if bad
Differentials for coughing
Upper respiratory tract disease
Inflammatory lower airway disease
Infectious - bacterial, viral and parasitic
FB
Neoplasia
Feline lungworm
Aelurostrongylus abstrusus
Paratenic hosts required
PPP 1-2 months
Most cats are asymptomatic
Presentation - young, mild coughing but can progress to dyspnoea.
Diagnosis and treatment of feline lungworm
Radiography similar to inflammatory disease
Airway wash
Consider faecal floatation
Treatment - fenbendazole
Mycoplasma pneumonia
Mycoplasma felis
Lower airway disease but may cause URT signs
CS - fever, cough, tachypnoea, lethargy
Treatment - doxycycline
Mycobacterial pneumonia
M.bovis/M.microti
Pneumonia= late stage systemic infections
Early cutaneous signs - bite from vole/rodent, non-healing sores/nodules
Early GI signs - contaminated milk ingestion, vomiting, diarrhoea, weight loss, poor appetite
Diagnosis - histopathology/PCR
Treatment - 6months rifampicin, pradofloxacin, azithromycin
Diagnostic plan for feline lower airway disease
Haematology/biochemistry
Diagnostic imaging
Faecal analysis
Bronchoscopy
Endotracheal wash
Treatment in an airway crisis
Management inflammation - dexamethasone IV
Manage bronchospasm
- tetrabutaline - smooth muscle relaxant, bronchodilation
- inhaled salbutamol
Oxygenate
Thoracic radiographs for feline LRT
Can be normal
Bronchial +/- interstitial pattern
Hyperinflation
Air trapping
Collapse of right middle lung lobe
Can have patchy alveolar pattern
Can have aerophagia
Thoracic radiographs for feline LRT
Can be normal
Bronchial +/- interstitial pattern
Can look hyperinflated
Air trapping
Collapse of right middle lung lobe
Can have patchy alveolar pattern
Can have aerophagia
Bronchoscopy
See - hyperaemia, oedema, excess mucous, decreased airway diameter
Complications - irritation, movement of mucous, bronchospasm
BAL cat
Cytology - eosinophilic inflammation suggests feline inflammatory disease, viral pneumonia, parasites hypereosinophilic syndrome
Culture
Mycoplasma PCR
Causes for breathing difficulties
Loss of thoracic capacity - pleural effusion, pneumothorax, neoplasia, ruptured diaphragm, abdominal abnormality, gross cardiomegaly
Clinical signs of pleural space disease
Restrictive breathing pattern - short shallow breaths
Tachypnoea
Open mouth breathing
Dyspnoea
Orthopnoea - elbow abduction, sternal recumbency
Cyanosis
Clinical exam for pleural space disease
Observe respiratory pattern
Percussion
Palpate apex beat
Pleural effusion
Muffled heart/lung sounds ventral when standing
Percussion - fluid line
Different fluids can be present
- transudate
- modified transudate
- exudates - non septic, septic, blood, chyle
Transudate pleural effusion
Pure transudate due to increased oncotic pressure due to hypoalbuminemia
Commonly caused by increased hydrostatic pressure secondary to right sided heart failure. Can be diaphragmatic hernias, lung lobe torsion, neoplasia
Septic Exudative pleural effusion causes
Non septic - fip, neoplasia, chronic chylothorax, chronic lung lobe torsion, fungal infection
Non septic exudative pleural effusion
Septic - penetrating chest wound, FB, ruptured oesophagus, ruptured pulmonary abscess/tumour, haematogenous bacterial spread
Can be hard to aspirate
Chylothorax causes
Disruption of thoracic duct
Lymphangiectasia, cranial vena cava obstruction, neoplasia, heart disease, fungal infection, lung lobe torsion, diaphragmatic hernia
Hemothorax causes
Trauma
Coagulopathy
Neoplasia
Lung lobe torsion
Diagnosis of pleural effusion
Clinical findings
Diagnostic imaging - ultrasound easy, xray also shows
Thoracocentesis - dorsal ribs space 7, asepsis, ultrasound for fluid pocket
Chest drain use
Animals that require multiple thoracocentesis over a short time period
Treatment for pneumothorax
Treat primary cause
Heart failure
Pericardial effusion - drainage
Pyothorax - antibiotics, systemic/local, lavage, long course
Chylothorax - diet/surgery
Pneumothorax
Rupture of major airway/lung parenchyma. Bullous, necrotizing or neoplastic lung disease
Clinical findings
- restrictive breathing
- auscultation, dull sounds dorsally, increased ventrally
- percussion - increased resonance
Diagnosis of pneumothorax
Physical exam
Respiratory assessment
Thoracic radiographs
Blood gases
Thoracic ultrasound
Pathophysiology of pneumothorax
Loss of negative pressure means lungs don’t inflate as ribcage is raised
Severity depends on degree of pneumothorax
Tension pneumothorax pathophysiology
Lesion in lung parenchyma acts as one way valve
Pleural pressure rises causing lung compression
Pressure can exceed venous pressure reducing venous return to heart
Rapidly life threatening
Treatment of pneumothorax
Oxygen
Drain but avoid over drainage
Some will require chest drains and heimlich valve
Can require surgery
What is spontaneous pneumothorax
Caused by ruptured pulmonary bulla or sub pleural bleb. Can occur with chronic asthma
CS - dyspnoea, anorexia, vomiting
Can require surgery
Prognosis depends on cause
Mediastinal disease
Benign/malignant tumours, cystic lesions, enlarged lymph nodes/haematomas
CT very useful, diagnosis challenging
Mediastinal lymphoma
Common in young cats
CS - tachypnea, inspiratory hyperpnoea, full heart sounds, pleural effusion
Treatment - chemo +/- radiotherapy
Thymoma
Rare - most common in older dogs
From thymic epithelium
Present with respiratory distress, cranial cabal syndrome, myasthenia gravis
Diagnosis - thoracic radiographs, cytology
Surgical resection best
Poor prognosis is old
Thyroid tumours
Sink into the thorax
Confirmation on scintigraphy
Treat with radioactive iodine or surgery
Pleural tumours
Rare
Causes large volume effusions and pain
Multifocal small masses, hard to image
Can do thoracoscopy histopathology best diagnosis
Treatment via intra-cavitady carboplatin/cisplatin
Rib tumours
Osteosarcoma/chondrosarcoma
Can be aggressive
Treatment = rib resection
Differentials for alveolar disease
Aspiration pneumonia
Pulmonary oedema
Pulmonary haemorrhage
Eosinophilic lung disease
Pulmonary parasites
Pulmonary neoplasia
Interstitial disease
Clinical signs of pulmonary parenchymal disease
Increased inspiratory and expiratory effort
Cough can be present
Can see haemoptysis, collapse/syncope, cyanosis
Lung crackles
Change in bronchovesicular sounds
Aspiration pneumonia
Signs - cough, harsh/reduced lung sounds, tachypnea, pyrexia
Radiographs for infiltrate - alveolar pattern with border obliteration and air bronchograms
BAL to confirm
Treat with supportive care, antibiotics, and underlying cause
Anti-biotics for alveolar disease
Select on C and S
Lipophilic best to penetrate the blood bronchus barrier
Bactericidal best
May need combination and long treatment period
Azithromycin has good distribution. Metronidazole accumulates well
Tetracyclines reasonable concentration
Penicillins variable
Mucolytic use in alveolar disease
Reduce mucous accumulation and helps with impaired muco-ciliary clearance
Bisolvon licensed
Pulmonary oedema causes
Increased hydrostatic pressure
Reduced oncotic pressure
Increased vascular permeability
Impaired lymphatic drainage
Leads to fluid accumulation in the interstitium
Differentiation between cardiogenic and non cardiogenic pulmonary oedema
Cardiogenic - low protein due to increased hydrostatic pressure without increased vascular permeability
Non-cardiogenic - lung damage leads to protein leaking through increased vascular permeability
Cardiogenic much more common
Non cardiogenic - alveolar disease
Damaged epithelium Increased vascular permeability leads to higher protein fluid in alveoli. Removal requires active transport so if epithelium damaged it wont occur. More refractory than cardiogenic
Causes
- hypoalbuminemia causes pulmonary oedema
- lymphatic drainage more likely to cause cylous effusion
- pulmonary epithelial injury most common due to things like choking, drowning, electric shock, head trauma, smoke inhalation and sirs
Physical lung injury
Pulmonary contusion - ventilation perfusion mismatch, chest wall damage/pain
Will have a lag phase before visible on radiographs
Supportive care
Eosinophilic lung disease
More common in dogs, young adults. Can be acute or chronic
Coughing and weightloss common
Diffuse bronchial interstitial pattern (doughnut pattern)
Circulating eosinophilia
BAL to diagnose
Oral Prednisolone for treatment
Angiostongylus vasorum
Nematode that lives in pulmonary arteries
Indirect lifestyle through slugs/snails
L1 penetrates capillaries into alveoli to be coughed up and swallowwd
Clinical signs of angiostongylus vasorum
Cardiorespiratory - chronic cough, dyspnoea, exercise intolerance, syncope, tachypnoea - relate to burden
Coagulopathies - anaemia, subcutaneous haematoma, internal haemorrhage, prolonged bleeding. Causes clotting failure (always test is unexplained clotting issue)
Neurological dysfunction - paresis, depression, seizures, spinal pain, behavioral changes, ataxia, vision loss
Diagnosis of angiostongylus vasorum
L1 in faeces - faecal floatation/smears
L1 in BAL
Radiography for alveolar infiltrates
Cage side snap
PCR on BAL/pharynx swabs
Management of angiostongylus vasorum
Licensed -
- imidacloprid and moxidectin
Or
- milbemycin oxime and praziquantal
Fenbendazole - effective but unlicensed
Treatment of angiostongylus vasorum
Supportive care in addition to anthelmintics
Bronchodilators
Corticosteroids
Phosphodiesterase inhibitor
Cage rest and oxygen therapy
Prevention
Interstitial pulmonary fibrosis
Middle age/older dogs
Chronic breathlessness, coughing, exercise intolerance, cyanosis, syncope, can faint
Clinical exam - crackles in lungs field. Prolonged expiratory phase with expiratory effort
Diagnosis of interstitial pulmonary fibrosis
Clinical signs
- pulmonary hypertension, interstitial/alveolar pattern, general cardiomegaly, abdo distension, hepatomegaly
Thoracic radiographs
CT
Bronchoscopy
Lung biopsy
Treatment of interstitial pulmonary fibrosis
Symptomatic treatment
Inhaled therapy - bronchodilator, corticosteroids
Oral therapy - bronchodilator and corticosteroids
Viagra effective for pulmonary hypertension
Normally live 1 year but up to 4
Interstitial pneumonias
Not common. Disease affects the interstitium
Associated with herpes virus
Metastatic disease
Often incidental finding
Most common = osteosarcoma, hemangiosarcoma, thyroid carcinoma, melanoma of mucocutaneous junction
Find Mets
Need CT to find how many/where. Care in seeding with thoracoscopy
Local chemo - penetration issues
