Pulmonary Parenchymal Disease Flashcards
What causes lung sounds seen in lung disease?
lung parenchyma fills with fluid (edema) or inflammatory cells (pneumonia), causing it to become less compliant and harder for the patient to breath
- tachypnea = increased rate
- hyperpnea = deeper breaths
- dyspnea = increased effort
What is the most common cause of pneumonia in dogs? What is the most characteristic sign? What else is seen?
bacterial
deep productive cough
- expiratory dyspnea
- tachypnea
- nasal discharge
- exercise intolerance, cyanosis, collapse
- SYSTEMIC: fever, lethargy, poor appetite
What is commonly seen on physical exams on patients with pneumonia?
- abnormal posture (orthopnea)
- abnormal lung sounds
- fever
- respiratory distress
- mucopurulent nasal discharge
- cyanosis
Diagnostics for lower airway disease:
What is important to note about radiographic changes of diseased lungs?
radiographic changes can lag behind clinical signs. of disease with pneumonia by about 1-2 days
- may not see anything on radiographs with acute disease
What does a vascular pattern on thoracic radiographs indicate? What are 3 causes?
enlarged and/or tortuous blood vessels result in increased soft tissue opacity in the lungs
- enlarged arteries
- elarged veins
- enlarged arteries and veins
What are the 3 causes of enlarged arteries seen on thoracic radiographs? Enlarged veins?
- heartworm disease
- pulmonary thromboembolism
- pulmonary hypertension
left-sided heart failure
What are 4 causes of enlarged arteries and veins (pulmonary overcirculation) seen on thoracic radiographs?
- left-to-right shunts
- patent ductus arteriosus
- ventricular septal defect
- atrial septal defect
What causes bronchial patterns on thoracic radiographs? What are some causes?
inflammation around the airways
- canine chronic bronchitis
- feline idiopathic bronchitis
- allergic bronchitis
- canine infectious respiratory disease complex (kennel cough)
- bacterial/Mycoplasmal infection
- pulmonary parasites
What causes alveolar patterns on thoracic radiographs? What are some causes?
airways stand out and are lined
- pulmonary edema
- severe inflammatory disease
- bacterial/aspiration/fungal pneumonia
- hemorrhage
- pulmonary contusion/thromboembolism
- neoplasia
- systemic coagulopathy
What causes nodular interstitial patterns? What are some examples?
nodular growths on lungs change its opacity
- neoplasia
- mycotic infection
- Blastomycosis/Histoplasmosis/Coccidiomycosis
- pulmonary parasites
- Aelurostrongylus/Paragnimus infection
- abscess/bacterial pneumonia
- FB
- eosinophilic lung disease
- idiopathic interstitial pneumonia
- inactive lesions
What causes interstitial patterns on thoracic radiographs? What are some examples?
subtle pattern on lung tissue
- mild pulmonary edema
- viral/bacterial/mycotic pneumonia
- Toxoplasmosis
- parasitic infection (more often bronchial/nodular)
- neoplasia
- eosinophilic lung disease
- idiopathic pulmonary fibrosis
- mild hemorrhage
How can lung lobe consolidation and atelectasis be differentiated on radiographs?
CONSOLIDATION = soft tissue opacity maintains space that the lobe fills, indicating it is filled with something
ATELECTASIS = opacity is secondary to airway obstruction or absorbed air, causing the lung lobe to collapse and lose volume, which can also cause shifting of the heart
How are cavitary lesions seen on thoracic radiographs?
localized accumulations of air or fluid due to rupture of bullae, blebs, abscesses, or cysts, and emphysema
How can lung lobe torsion be seen on thoracic radiographs?
vesicular gas pattern and alveolar patterns with abrupt truncation near the hilus
- air is trapped in the lung lobe
How is ultrasound used as a diagnostic for lower airway disease?
cannot see through air, but can see fluid-filled or dense tissue
In what situation is CT and MRI a good diagnostic for lower airway disease?
small nodules and suspected fibrosis
In what 2 situations is nuclear imaging especially helpful in diagnosing lower respiratory disease?
- can measure mucociliary clearance by placing a drop of technetium-labeled albumin at the carina and observing its movement with a gamma camera for diagnosing ciliary dyskinesia
- can measure pulmonary perfusion and ventilation for diagnosing pulmonary thomboembolism
For what 7 organisms is serology a helpful diagnostic?
- Histoplasmosis
- Blastomycosis
- Coccidiomycosis
- Toxoplasma
- Feline Coronavirus
- Cryptococcus
- Heartworm tests
For what 2 organisms is urine antigen testing a useful diagnostic?
- Histoplasmosis
- Blastomycosis (more sensitive than serology)
What cardiovascular marker can be used for diagnosing lung disease? Why is it used?
NT-proBNP —> hormone produced by cardiac muscle cells in response to cellular stretch
can be used as an in-house test to tell if an animal with trouble breathing is caused by cardiac or respiratory disease
How are NT-proBNP levels used for diagnosing cardiovascular or respiratory causes of coughing?
- normal/low NT-proBNP = respiratory cause more likely
- elevated NT-proBNP = cardiac disease associated
can have more than one issue, need full assessment still
How is blood gas used as a diagnostic for lung disease?
in severe cases of impeding respiratory failure, there will be hypercarbia with concurrent respiratory acidosis and hypoxemia
What are the most common causes of bacterial pneumonia in younger and older dogs? What does a definitive diagnosis rely on?
- YOUNG = viral infection followed by bacterial invasion
- OLDER = aspiration and foreign bodies
detection of intracellular bacteria in airway cytology or clinically significant bacterial growth from an airway sample
Is primary or secondary bacterial pneumonia most common?
SECONDARY —> resident flora grow out of control due to another issue, rare to see healthy adults get spontaneous pneumonia
What are the 3 most common primary/community-acquired pathogens that cause bacterial pneumonia? What others have been isolated?
- Bordetella
- Mycoplasma
- Streptococcus
E. coli, Klebsiella pneumonia, Pseudomonas, Enterococcus, Pasteurella multocida, Bacillus, Staph, Fusobacterium
What are the 3 most common causes of secondary bacterial pneumonia? What history is most commong?
- aspiration
- foreign bodies
- immune dysfunction
- laryngeal or esophageal dysfunction
- poor upper airway conformation
- neurologic signs
- hospital-acquired from anesthesia or sedation
What are the most common signs of bacterial pneumonia? Why may it not be noticed immediately?
- lethargic, fever
- anorexic
- cough
- exercise intolerance, collapse, respiratory distress
- tachypnea, increased effort
- mucopurulent nasal discharge
- increased lung sounds (crackles)
dogs that do not exercise as much are not moving oxygen as much