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 TBCavitatingMiliary TB

Adenocarcinoma Squamous cell carcinoma Small cell carcinoma

Bronchioloalveolar carcinoma

Hamartoma

Mesothelioma