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Question 1

Respiratory diseases common in

Answer 1

Production animals, less common in horses and companion animals

Question 2

Upper Resp Tract components

Answer 2

Nasal cavity, sinuses, larynx, trachea, extra pulmonary bronchus, intrapulmonary bronchus

Question 3

Lower Resp Tract components

Answer 3

Primary, secondary & tertiary bronchioles, resp. bronchiole, alveolar duct, atrium, alveolar sac, alveolus

Question 4

Infection enter the lungs via

Answer 4

Inhales air or haematogenous route

Question 5

Pulmonary Defence Mech

Answer 5

1)Nasal Turbinates - Turbulence, Particle deposition 2)Mucociliary apparatus 3)Inflammatory cells - Alveolar macrophages, BALT (Bronchial-associated Lymphoid Tissue), Inflammatory cells via bloodstream

Question 6

Mucociliary Escalator funct & makeup

Answer 6

To remove trapped particles. Ciliated, pseudostratified columnar epithelium and goblet cells are found in the nasal cavity, trachea, and bronchi of lungs

Question 7

Mucociliary Escalator process

Answer 7

Mucus, produced by Goblet cells, traps particles > Cilia moves trapped particulate matter: Out of nasal cavity towards nostrils or pharynx, Out of lung, up the trachea towards larynx to be swallowed. Mucus also contains IgA and lysozyme

Question 8

Diseases which affect the cilia function

Answer 8

Immotile Cilia Syndrome (Cilia Dyskinesis) & Bronchiectasis

Question 9

Immotile Cilia Syndrome (Cilia Dyskinesis)

Answer 9

Rare disease of humans and dogs caused by ultrastructural defects in cilia all over the body.
Results in rhinitis, bronchopneumonia, bronchiectasis

Question 10

Bronchiectasis

Answer 10

Lack of cilia leads to retention of mucus + bacteria

Leads to inflammation which damages and weakens wall of bronchi > Dilation (ectasia) of bronchi

Question 11

Alveolar macrophages properties

Answer 11

1)Front-line of defence 2)Phagocytose & kill microoraganism 3)Secret a variety of cytokines & enzymes 4)Repopulated from monocytes 5)Migrate to bronchioles & removed by mucociliary apparatus

Question 12

Bronchial associated lympoid tissue

Answer 12

Alveolar macrophages, T cells and B cells

Question 13

General lung disorders

Answer 13

1) Congestion and edema
2) Thrombosis and embolism
3) Infarction
4) Atelectasis
5) Emphysema

Question 14

Pulmonary hyperaemia and congestion

Answer 14

Reddening of lungs due to increased blood in capillaries and larger vessels

Question 15

Hyperaemia is an

Answer 15

Active process - part of acute inflammation

Question 16

Congestion is

Answer 16

Passive - associated with reduced venous drainage (e.g. heart failure, barbiturate euthanasia)

Question 17

Pulmonary hyperaemia and congestion is often combines with

Answer 17

Pulmonary Oedema

Question 18

What is Hypostatic congestion

Answer 18

Accumulation of blood on one side of the lungs, due to gravity

Question 19

Pulmonary oedema is

Answer 19

Wet, heavy, lungs due to fluid loss into airways

Question 20

Causes of Pulmonary oedema

Answer 20

1) Increased hydrostatic pressure (e.g. left-sided heart failure > congestion of blood vessels)
2) Vascular endothelial injury > increased permeability (e.g. enterotoxaemia)
3) Injury to Type I alveolar epithelial cells (e.g. certain toxins and viruses)
4) Fluid overload
5) Barbiturate euthanasia
6) Decreased plasma oncotic pressure 7)Lymphatic obstruction

Question 21

Pulmonary oedema clinical signs

Answer 21

Frothy fluid exuding from the nostrils, the trachea will be full of similar foam and the lungs will be wet and heavy.

Question 22

Explain how Endocarditis of mitral valve cause congestion and oedema

Answer 22

Valves can’t close properly > during systole blood leaks back into the atrium & large pulmonary veins > eventually back up into alveolar capillaries > Congestion & Oedema

Question 23

Damage to alveolar-capillary lining sequelae

Answer 23

1) Minor damage: fluid from leaks from vascular space into alveolar space
2) Moderate damage: fluid accompanied by protein (including fibrin)
3) Severe damage: fluid, protein, red blood cells (hemorrhage)
4) Acute Respiratory Distress Syndrome (ARDS)

Question 24

Causes of decreased plasma oncotic pressure

Answer 24

1)Chronic nephritis - loss of albumin through damaged glomeruli 2)Liver cirrhosis - decreased production of albumin

Question 25

Causes of Lymphatic obstruction

Answer 25

Metastatic melanoma of the lungs

Question 26

Cause of Endothelial Injury

Answer 26

Heartworm aka Dirofilaria immitis. Adult worms irritate and obstruct branches of pulmonary artery

Question 27

Pulmonary Embolism types

Answer 27

1) Thrombo-embolus originating elsewhere in vasculature 2) Septic (bacterial) embolus 3) Tumour cell embolus 4) Fat (bone marrow) embolus

Question 28

Outcome of embolus

Answer 28

Infarcts, usually at the tip of the lobe (can ba avoided due to dual blood suppy to the lung) > (major blockage) acute onset of dyspnea secondary to massive hypoxia > death

Question 29

Abnormalities of Inflation

Answer 29

1)Atelectasis vs. 2)Emphysema

Question 30

Atelectasis definition

Answer 30

Incomplete expansion of pulmonary airways. Affected areas are dark red/purple and fleshy

Question 31

Atelectasis types

Answer 31

1) Congenital - fetal lungs that have never been inflated | 2) Acquired (alveolar collapse) - due to airway obstruction or compression of lungs

Question 32

Causes of congenital atelectasis

Answer 32

1)Fetal stillbirth; no respiration, no lung inflation 2)Dystocia - Fetal hypoxia > Depression of Respiratory centers in CNS > Hypoinflation 3)Premature birth; lack of production of surfactant

Question 33

Acquired obstructive atelectasis

Answer 33

Obstruction of distal airways due to 1)Inflammation 2)Parasites e.g. Aelurostrongylus

Question 34

Acquired compressive atelectasis is due to

Answer 34

Pyothorax or Chylothorax

Question 35

Pyothorax is

Answer 35

An accumulation of pus in the pleural cavity that can develop when bacteria invade the pleural space, usually in the context of a pneumonia.

Question 36

Chylothorax is

Answer 36

Lymphatic fluid accumulating in the pleural cavity

Question 37

Emphysema is

Answer 37

Permanent excess air accumulation in the lung

Question 38

Emphysema types

Answer 38

1)Alveolar Emphysema - humans Enzymatic destruction of alveolar walls results in excessive accumulation of air in the lungs 2)Interstitial Emphysema - ruminants Forced expiration causes bronchiolar collapse resulting in alveolar rupture & leakage of air into interlobular septae

Question 39

Interstial emphysema pathogenesis

Answer 39

Bronchopneumonia, acute interstitial pneumonia > Forced expiration > Bronchioles collapse > Air trapped distally in alveoli > Air filled alveoli rupture & air leaks into interlobular septae