Respiratory Pathology 4 Flashcards
What are the four types of atelectasis?
Obstructive
Compression
Massive
Recumbencey
What is atelectasis?
Incomplete expansion of the lung. Can be congenital or acquired
What is obstructive atelectasis?
Complete or segmental obstruction by inflammatory exudate, foreign bodies or tumours.
Ruminants only need segmental as they have poor collateral blood supply, dogs and cats need complete
What is compression atelectasis?
Cause d by pleural, intrathoracic, intrapulmonary space occupying lesions e.g hydro or haemothorax
What is massive atelectasis?
Complete lung collapse by pneumothorax
What is recumbency atelectasis?
Defective surfactant production
What type of emphysema do our spp get and what are the two types?
Secondary which causes distension of the alveoli and rupture of the walls-air bubbles.
Interstitial is common in cattle which causes bulbous emphysema
What are the 3 protective mechanisms against pulmonary oedema?
Intercellular junctions are highly permeable to seal off alveoli.
Interstitium of alveolar septa is lower pressure than the intra alveolar pressure
Interstitial pressure is more negative towards the fascia and airways
How does pulmonary oedema begin and what does it progress to?
Begins as interstitial oedema and progresses to alveolar oedema, once the interstitial compartment is overwhelmed
What are the 3 causes of pulmonary oedema?
Increased capillary or epithelial permeability (shock, toxins)
Increased capillary hydrostatic pressure.
Decreased plasma oncotic pressure
What type of haemorrhage is seen in horses?
Exercise induced pulmonary haemorrhage
Why does infarction not usually follow embolism or thrombosis in the lung?
Supplied by both pulmonic and bronchial arteries and it has extensive collateral channels. Only occurs if the pulm circ is compromised
What causes pulmonary hypertension?
Increased resistance in the pulmonary vasculature or left to right shunts.
What is a sequelae of pulmonary hypertension ?
Coe pulmonale, r sided heart failure
Examples of neoplasia in the upper airway?
Carcinoma or adenocarcinoma
Lymphosarcoma
Examples of neoplasia of the lower airway?
Bronchial papilloma
Bronchioalveolar carcinoma
What agent causes Sheep pulmonary adenomatosis?
Jaagsiekte,
What is the gross pathology of sheep pulmonary adenomatosis?
Small firm white nodules to replacement by neoplasticism tissue. Metastasise to LNs
What are three examples of Metastatic tumours?
Mammary carcinoma in dog and cat
Uterine adenocarcinoma cattle
Malignant melanoma in horses
What is pneumothorax?
Air in the pleural cavity
What are hydro thorax, chylothorax and haemothorax examples of?
Non inflammatory pleural effusions.
Chylomicron rich lymph by trauma to the thoracic lymphatic duct (chylothorax) dorsal aspect of the thoracic aorta
What aw the five ways that inflammatory agents reach the pleura?
Extension pneumonia Bloodstream Trans diaphragmatic Penetration of chest Penetration of the oeasophagus or abdominal viscus
What are the two types of acute pleuritis?
Purulent and fibrinous
What is a chronic sequelae of pleuritis?
The visceral pleura become enveloped in a fibrinous blanket and pleural adhesions
What is pyothorax?
Puerile by effusion in the pleural space.
What is pyothorax caused by?
Streptococci in dogs.
P multocida in cats
What is an example of a degenerative pleural disease?
Pleural mineralisation in dogs with uraemia and vit D toxicity
What is mesothelioma?
Common in calves, thoracic effusion, multiple nodules.
