Respiratory Tutorial
Dec 25, 2015
Respiratory Tutorial
Pulmonary oedema
• Causes– Haemodynamic
• Increased hydrostatic pressure – (heart failure, mitral stenosis, volume overload)
• Decreased oncotic pressure– Hypoalbuminaemia
• Lymphatic obstruction
– Microvascular injury• Infections (sepsis/viral/Mycoplasma)• Toxic injury (gases/aspirated liquids/drugs/chemotherapy)• Trauma, shock, DIC, emboli, heat• Uraemia, pancreatitis• Extracorporeal circulation
Pulmonary oedema
• Gross findings
Pulmonary oedema
• Microscopic findings
Pulmonary oedema
• Microscopic findings
ARDS/Diffuse Alveolar Damage
• Damage to what?– Diffuse alveolar capillary damage
• Presentation– Oedema, resp failure, hypoxia resistent to O2
• Pathogenesis– Endothelial damage– Increased vasc permeability
• Fibrin exudation – membrane formation• Inflammatory cell infiltrate in alveolar septum
• Causes
ARDS/Diffuse Alveolar Damage
• Gross findings
ARDS/Diffuse Alveolar Damage
• Microscopic findings
Pulmonary Emboli
• Types of emboli?• Majority thromboemboli
– Majority from deep leg veins
• Risk factors– Surgery, immobility, old age– Hypercoagulability, pregnancy, OCP,
malignancy, esp gynae malignancy– Trauma, burns, fracture
Saddle embolus; sudden death
Large embolus; acute right heart failure
Medium embolus; pulmonary infarct
Small embolus; +/- infarct depending on circulatory status
Pulmonary Emboli
• Consequences– Embolus
• Resolution• Organization• Vascular sclerosis• Pulm HTN• Chronic cor pulmonale
– Infarct• Organization
Pulmonary Hypertension
• Causes– Chronic lung disease (interstitial or COPD)– Chronic left heart failure– Recurrent pulmonary emboli– Primary / idiopathic
• Pathogenesis– Endothelial injury– Vasoconstriction– Medial hypertrophy– Intimal fibrosis
Pulmonary Hypertension
• Histology– Large arteries: Atheroma– Medial and small arteries
COPD
• Emphysema• Abn. Enlargement of airways distal to terminal bronchioles with
destruction of walls
• Bronchitis• Persistent cough with sputum x 3/12 x 2 conseq years
• Asthma• Chronic inflammatory disorder with hyper-responsiveness &
paroxysmal contraction of bronchial tree
• Bronchiectasis• Chronic necrotizing infection of bronchi & bronchioles with abn
permanent dilatation of their walls
What type?
Pathogenesis?
Emphysema
• Microscopic findings
Bronchitis
• Pathogenesis– Chronic irritation of airways
• Inflammation, congestion, edema• Increased mucus secretion
– Mucous gland hypertrophy in bronchi– Goblet cell metaplasia in bronchioles
• Secondary infection
– Morphology• Inflamed bronchi with thickening of mucus layer• Mucous plugs• Fibrosis• Squamous metaplasia• Squamous dysplasia
Asthma
• Types– Extrinsic (atopic)– Intrinsic (non-atopic)
• Pathogenesis– Atopic:
• Antigen binding to IgE on mast cell – acute phase• Cytokine release – late phase
• Morphology– Gross:
• Overinflation with mucus plugging
– Micro:• Edema, inflammation, mucous gl and smooth m hypertrophy
What type of COPD?
Causes?
Pathogenesis?
Obstruction
Atelectasis
Infection
Necrosis of bronchial walls
Irreversible dilation
What is this?
Causes?
Morphology?
Consequences?
What is this?
Causes?
Morphology?
Consequences?
What is this?
Morphology?
Consequences?
Secondary TB Cavitating Miliary TB
Adenocarcinoma Squamous cell carcinoma Small cell carcinoma
Adenocarcinoma Squamous cell carcinoma Small cell carcinoma
Bronchioloalveolar carcinoma
Hamartoma
Mesothelioma