Respiratory Flashcards
What is the definition of chronic obstructive pulmonary disease (COPD)?
A chronic lung condition characterised by breathlessness due to poorly reversible and progressive airflow obstruction. It consists of chronic bronchitis and emphysema
What is the aetiology of chronic obstructive pulmonary disease (COPD)?
Tobacco smoking, workplace exposure to dust, alpha-1 anti-trypsin deficiency
What is the pathophysiology of chronic obstructive pulmonary disease (COPD)?
In emphysema, irritants and chemicals trigger inflammatory mediators to release matrix destructive enzymes which leads to elastin destruction and enlargement of alveolar air spaces and results in air trapping.
What is the clinical presentation of chronic obstructive pulmonary disease (COPD)?
Sudden onset of exertional breathlessness on a background of prolonged cough and sputum production, wheeze, finger clubbing
What are the investigations of chronic obstructive pulmonary disease (COPD)?
o Spirometry:
oFEV1 < 0.8
oFEV1/FVC < 0.7
o Chest X-ray: hyperinflation
What is the treatment of chronic obstructive pulmonary disease (COPD)?
Smoking cessation, anti-mucolytic treatment
o Short-acting beta-2 agonist for symptom relief (salbutamol) or short-acting muscarinic antagonist (ipratropium bromide)
o Long-acting beta-2 agonist (salmeterol), long-acting muscarinic antagonist (tiotropium bromide), inhaled corticosteroid (budesonide)
o Long-term oxygen therapy
What is the definition of asthma?
Chronic inflammatory disorder of large airways characterised by recurrent episodes of reversible airway narrowing
What is the aetiology of asthma?
Triggered by cold air, exercise, cigarette smoke, air pollution, allergens
What is the clinical presentation of asthma?
Wheeze (widespread, polyphonic), breathlessness, chest tightness, dry cough (particularly at night)
What are the investigations of asthma?
o Spirometry: oFEV1 < 0.8 oFEV1/FVC < 0.7 o15% improvement in FEV1 or PEFR following the inhalation of a bronchodilator o Peak flow measurement: variable o Chest X-ray: hyperinflation
What is the treatment of asthma?
o Short-acting beta-2 agonist for symptom relief (salbutamol, terbutaline)
o Standard dose inhaled corticosteroid daily (budesonide)
o Leukotriene receptor antagonist (montelukast)
o Long-acting beta-2 agonist (salmeterol)
o Increase inhaled corticosteroid dose
What is the criteria of moderate acute asthma?
Increasing symptoms, peak flow > 50-75% best or predicted
What is the criteria of severe acute asthma?
Peak flow 33-50% best or predicted, respiratory rate ≥ 25/min, heart rate ≥ 110/min, inability to complete sentences in one breath
What is the criteria of life-threatening acute asthma?
Peak flow < 33% best or predicted, arterial oxygen saturation (SpO2) < 92%, partial arterial pressure of oxygen (PaO2) < 8kPa, normal partial arterial pressure of carbon dioxide (PaCO2), silent chest, cyanosis, poor respiratory effort, arrythmia, exhaustion, altered conscious level, hypotension
What is the criteria of near-fatal acute asthma?
Raised PaCO2 and/or the need for mechanical ventilation with raised inflation pressures
What is the definition of respiratory failure?
PO2 < 8kPa
o Type 1: normal or low pCO2
o Type 2: high pCO2
What is the aetiology of respiratory failure?
o Type 1: severe pneumonia, pulmonary embolism, acute asthma, pulmonary fibrosis (ventilation/perfusion mismatch)
o Type 2: COPD (alveolar hypoventilation)
What is the clinical presentation of respiratory failure?
Hypoxia (dyspnoea, restlessness, agitation, confusion, central cyanosis)
Hypercapnia (headache, peripheral vasodilation, tachycardia, bounding pulse, tremor/flap, papilledema, confusion, drowsiness, coma)
What is the treatment of respiratory failure?
Treat underlying cause, oxygen therapy
What is the definition of hypersensitivity pneumonitis?
Interstitial lung disease caused by a hypersensitivity immune reaction to inhaled antigens
What is the aetiology of hypersensitivity pneumonitis?
Thermophilic bacteria (mouldy hay, cheese), fungi, avian proteins (bird faeces)
What is the clinical presentation of hypersensitivity pneumonitis?
Breathlessness, cough, fever, malaise, weight loss
What are the investigations of hypersensitivity pneumonitis?
o CT: interstitial opacities (mottling) and small nodules
o Bronchoalveolar lavage: raised lymphocytes, mast cells
What is the treatment of hypersensitivity pneumonitis?
Identify causative agent and avoid exposure, prednisolone
What is the definition of idiopathic pulmonary fibrosis?
Formation of scar tissue within the lungs with no known cause
What is the clinical presentation of idiopathic pulmonary fibrosis?
Dyspnoea, dry cough, bibasal crackles, malaise, weight loss, arthralgia, cyanosis, finger clubbing, fine end-inspiratory crepitations
What are the investigations of idiopathic pulmonary fibrosis?
High resolution CT: ground glass/honeycomb appearance, decreased volume
What is the treatment of idiopathic pulmonary fibrosis?
Smoking cessation, pirfenidone, nintedanib, lung transplant
What is the definition of Goodpasture’s syndrome?
Autoimmune anti-glomerular basement membrane (anti-GBM) disease, where antibodies attack the basement membrane (IV collagen) in the lungs and the kidney
What is the clinical presentation of Goodpasture’s syndrome?
o Renal: oliguria/anuria, haematuria, acute kidney injury, renal failure
o Pulmonary: pulmonary haemorrhage, shortness of breath, haemoptysis
What are the investigations of Goodpasture’s syndrome?
Lung and kidney biopsy: anti-GBM antibodies
What is the treatment of Goodpasture’s syndrome?
Supportive, corticosteroids, immunosuppressants, plasmapheresis
What is the definition of bronchiectasis?
Abnormal dilation of bronchi accompanied by inflammation in their walls and adjacent lung parenchyma and excess mucus secretion
What is the pathophysiology of bronchiectasis?
Scarring the adjacent lung parenchyma places traction on the weakened bronchi, causing them to permanently dilate
What is the clinical presentation of bronchiectasis?
Persistent cough, copious purulent (green) sputum, intermittent haemoptysis, finger clubbing, course inspiratory crepitations, wheeze
What are the investigations of bronchiectasis?
o Sputum culture
o Chest X-ray: cystic shadows, dilated bronchi with thickened walls (Signet ring sign)
What is the treatment of bronchiectasis?
Airway clearance techniques and mucolytics, bronchodilators
What is the definition of cystic fibrosis?
Autosomal recessive inherited disorder caused by a mutation in the cystic fibrosis transmembrane conductance regulator (CFTC) gene on chromosome 7
What is the clinical presentation of cystic fibrosis?
o Neonates: failure to thrive, meconium ileus, rectal prolapse
o Children and young adults:
oRespiratory: cough, wheeze, recurrent infections
oGI: pancreatic insufficiency, gallstones, cirrhosis
oOther: male infertility, osteoporosis, arthritis, vasculitis, nasal polyps
What are the investigations of cystic fibrosis?
o Sweat test: chlorine > sodium
o Cystic fibrosis genotyping
What is the treatment of cystic fibrosis?
Chest physiotherapy, antibiotics, bronchodilator, pancreatic enzyme replacement, fat-soluble vitamin supplements
o Advanced disease: oxygen, diuretics, non-invasive ventilation, lung transplant
What is the definition of a pleural effusion?
Accumulation of excess fluid within the pleural space
What is the aetiology of a pleural effusion?
Left ventricular failure, pneumonia, pulmonary embolism, malignancy
What is the clinical presentation of a pleural effusion?
Dyspnoea, dullness to percussion, cough, quieter breath sounds, pleuritic chest pain, decreased expansion
What are the investigations of a pleural effusion?
o Chest X-ray: blunt costophrenic angles, water-dense shadows
o Ultrasound
o Thoracocentesis
What is the treatment of a pleural effusion?
Depends on the underlying cause (loop diuretics, antibiotics, therapeutic thoracentesis)
What is the definition of a pneumothorax?
Presence of air within the pleural space
What is the pathophysiology of a pneumothorax?
Air leaks out of the damaged lung into the pleural space until the pressures equalise, causing the lung to collapse
What is the clinical presentation of a pneumothorax?
Sudden onset unilateral pleuritic chest pain, breathlessness
What are the investigations of a pneumothorax?
Chest X-ray: reduced/absent markings between lung margin and chest wall
What is the treatment of a pneumothorax?
Chest drain (needle aspiration)
What is the definition of a tension pneumothorax?
Air enters the pleural space with inspiration but does not exit on expiration causing respiratory distress
What is the treatment of a tension pneumothorax?
Immediate decompression (large bore cannula into the pleural space)
What is the definition of pulmonary hypertension?
Pulmonary artery pressure > 25 mmHg at rest or > 30 mmHg during exercise
What is the aetiology of pulmonary hypertension?
COPD, interstitial lung disease, left ventricular failure, pulmonary embolus
What is the pathophysiology of pulmonary hypertension?
Vasoconstriction, smooth muscle and endothelial cell proliferation, thrombosis
What is the clinical presentation of pulmonary hypertension?
Exertional dyspnoea, fatigue, dizziness, syncope, tricuspid regurgitation murmur, peripheral oedema
What are the investigations of pulmonary hypertension?
o Chest X-ray: enlarged proximal pulmonary arteries which taper distally
o ECG: RVH and P pulmonale (peaked P waves)
o Echocardiogram: right ventricular dilation/heart failure
What is the treatment of pulmonary hypertension?
Oxygen, anti-coagulation, diuretics for oedema, calcium channel blockers (pulmonary vasodilators)
What is the definition of a pulmonary embolism?
Occlusion of a pulmonary artery by an embolic thrombus, usually from a deep vein thrombosis
What is the clinical presentation of a pulmonary embolism?
Acute onset dyspnoea, pleuritic chest pain, DVT, cough, haemoptysis, hypoxaemia, crepitations
What are the investigations of a pulmonary embolism?
o D-dimer: elevated
o Chest X-ray: normal, oligaemia of affected segment
o Pulmonary CT angiography
What is the treatment of a pulmonary embolism?
Oxygen, aspirin, analgesia, thrombosis (alteplase), LMWH
What score determines the likelihood of a pulmonary embolism?
The Well’s score
What is the definition of tuberculosis?
Aerobic, non-motile, non-sporing, slightly curved bacilli with a thick waxy capsule, acid fast, slow growing, resistant to phagolysosomal killing
What is the pathophysiology of tuberculosis?
o Alveolar macrophages ingest bacteria, and the rods proliferate inside
o Macrophages drain into hilar lymph nodes, present antigen to T lymphocytes, and cause a cellular immune response
o Delayed hypersensitivity reaction causes tissue necrosis and granuloma formation (caseating)
What is the clinical presentation of tuberculosis?
o Systemic: weight loss, low grade fever, anorexia, drenching night sweats, malaise
o Pulmonary symptoms: productive cough (> 3 weeks), haemoptysis, breathlessness
o Signs: dull to percuss, decreased breathing, crackles
What are the investigations of tuberculosis?
o Chest X-ray: fibronodular opacities on upper lobes
o Sputum culture: Ziehl-Neelsen stain
o Biopsy: caseating granuloma
o PCR
What is the treatment of tuberculosis?
o Rifampicin (6 months) – red urine o Isoniazid (6 months) o Pyrazinamide (2 months) – gout o Ethambutol (2 months) – optic neuritis
What is the definition of pneumonia?
An infection of the lung parenchyma caused by bacterial organism
What is the aetiology of pneumonia?
o Community Acquired: streptococcus pneumoniae, mycoplasma pneumoniae, Haemophilus influenzae
o Hospital Acquired: aerobic-gram negative bacilli (pseudomonas aeruginosa, e. coli, klebsiella pneumoniae)
o Immunocompromised: pneumocystis jirovecii
What is the pathophysiology of pneumonia?
Invasion and overgrowth of a pathogen in the lung parenchyma causes overwhelming of host immune defences and leads to the production of intra-alveolar exudates
What is the clinical presentation of pneumonia?
Productive cough, breathlessness, chest pain, fever, haemoptysis, pyrexia, cyanosis, confusion, tachypnoea, tachycardia
What are the investigations of pneumonia?
o Sputum: microscopy and culture (rusty sputum = strep pneumoniae)
o Chest X-ray: lobar or multilobar infiltrates, cavitation, pleural effusion
oMulti-lobar is suggestive of S.pneumoniae, S.aureus & Legionella spp.
oMultiple abscesses is suggestive of S.aureus
oUpper lobe cavity is suggestive Klebsiella pneumoniae
What is the treatment of pneumonia?
Antibiotics, oxygen, fluids, analgesia
What score predicts mortality in community-acquired pneumonia?
CURB65 (Confusion, urea < 7, respiratory rate > 30, BP < 90/60, age >65)
o 0-1: outpatient treatment
o 2 – short-stay inpatient treatment or hospital-supervised outpatient treatment
o 3-5 – high severity pneumonia
What are the investigations of occupational lung disorders?
X-ray: fine micro nodular shadowing
What are the investigations of silicosis?
X-ray: diffuse nodular pattern in upper and mid-zone and thin streaks of calcification (egg-shell calcification) of the hilar nodes
What is the clinical presentation of sarcoidosis?
Bilateral hilar lymphadenopathy, pulmonary infiltration and skin or eye lesions
What do sarcoid granulomas consist of?
focal accumulations of epithelioid cells, macrophages, and lymphocytes (mainly T cells)
What can respiratory syncytial viruses cause?
Bronchiolitis (inflammation of the bronchioles and increased mucus secretions)
What is Bordetella pertussis?
Gram-negative coccobacillus which causes whooping cough
