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Respiratory Disease Pathophysiology

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Obstructive Pulmonary Disease

eg. COPD, asthma

broncho-constriction or inflammation leading to inability to take in enough air

Diffusion Pulmonary Disease

eg. edema (heart failure, pneumonia) or circulatory failure (MI, shock, embolus)

gas can't diffuse at alveoli due to lack of perfusion

Restrictive Pulmonary Disease

eg. fibrosis, pneumothorax, hemothorax

Lung can't expand or ventilate

Ventilation Pulmonary Disease

eg. Depressants (narcotics, benzodiazepines, barbituates, alcohol) or CNS disruption (stroke, seizure, tumour, trauma)

loss of CNS control of respiratory system


dyspnea while lying down due to fluid accumulation

pursed lip breathing

increases pressure of inspiration to keep airways open


whistling sound on expiration due to high air turbulence

wet cough

excess fluid cough


harsh inspiratory sound due to obstruction

fine crackles

paper tearing sound due to fluid in small airway

course crackles

sucking last bit of liquid from straw sound due to flui in large airway

dry cough

irritated cough

Chest XRAY

fluid and bones absorb xray and appear white on screen. helps locate edema

Perfusion Scan

See which parts of lung blood can go

Ventilation Scan

See where air can go in lungs

Pulmonary Angiography

Locate embolus

CT scan (Spiral Computed Axial Tomography)

find tumours