Respiratory Flashcards
what two disease are included within the definition of COPD?
emphysema and chronic bronchitis
define chronic bronchitis
persistent cough for 3/12 for 2 consecutive years
list some features that would suggest it is more likely the patient has COPD than asthma
onset >35yo, smoking/pollution related, chronic dyspnoea (instead of attacks), sputum production, lack of diurnal FEV1 variation
give 2 causes of COPD
smoking, exposure to pollutants at work (mining, building, chemical), alpha-1 antitrypsin deficiency
what generally causes early-onset COPD?
alpha-1 antitrypsin deficiency
give 3 risk factors of COPD
smoking, pollutant exposure, frequent lower resp infections in childhood, age.
describe the pathology seen in chronic bronchitis
narrow airways. hypertrophy and hyperplasia of mucus secreting glands of the bronchial tree.
bronchial wall inflammation. mucosal oedema.
ulceration of epithelial layer - heals squamous instead of columnar (squamous metaplasia).
describe the pathology seen in emphysema
dilation and destruction of alveoli - leads to loss of elastic recoil - expiratory airflow limitation and air trapping
which disease is predominant in each of pink puffers and blue bloaters?
pink puffers = predominantly emphysema
blue boaters = predominantly chronic bronchitis
what are the features of a pink puffer?
increased alveolar ventilation - nearly normal PaO2 + normal/low PaCO2 - breathless but not cyanosed - may progress to type 1 resp failure
what are the features of a blue bloater?
decreased alveolar ventilation - low PaO2 and high PaCO2 - cyanosed but not breathless - poss. cor pulmonale - rely on hypoxic drive as respiratory centres are insensitive to CO2
what is cor pulmonale?
enlargement and failure of right side of the heart due to disease of lungs/pulmonary blood vessels - leads to oedema and raised JVP
explain how cigarette smoke causes COPD
causes mucous gland hypertrophy in larger airways - increase in neutrophils, macrophages and lymphocytes in airway walls - release of inflammatory mediators - inflammatory cells attracted - structural changes - break down of connective tissue
what is alpha1-antitrypsin?
a protease inhibitor - inactivated by cigarette smoke
give 3 symptoms of COPD
cough, sputum, dyspnoea, wheeze
give 3 signs of COPD
tachypnoea, use of accessory muscles of respiration, hyperinflation, decreased cricosternal distance, resonant/hyperresonant percussion, quiet breath sounds, wheeze, cyanosis, cor pulmonale
give 3 complications of COPD
acute exacerbations ± infection, polycythaemia, respiratory failure cor pulmonale, pneumothorax, lung carcinoma
give 3 differential diagnoses of COPD
asthma, bronchiectasis, pulmonary embolism, congestive heart failure, pneumothorax
what would be the results of a lung function test in a COPD patient?
reduced FEV1/FVC ratio, reduced PEFR.
raised TLC.
obstructive pattern.
what might you see on CXR in a COPD patient?
hyperinflation, flat hemidiaphragms, large central pulmonary arteries, decreased peripheral vascular markings, bullae.
how would you conduct a steroid trial in COPD? what information would it give you?
patient given oral prednisolone for 2 wks.
if FEV1 rises by >15% the COPD is steroid responsive - will benefit from long-term inhaled corticosteroids
how would you treat COPD?
ipratropium - short-acting antimuscarinic
± short-acting beta2 agonist -salbutamol, terbutamine
± inhaled tiotropium bromide - long-acting antimuscarinic
± long-acting beta2 agonist - salmeterol, formoterol
Severe COPD:
combination LABA + corticosteroids - Symbicort (budesonide + formoterol).
OR - tiotropium + inhaled steroid + LABA
describe non-pharmacological treatment of COPD
pulmonary rehab programmes.
smoking cessation.
low BMI = diet advice ± supplements.
long-term oxygen therapy.
describe the features of the airway obstruction seen in asthma
reversible.
bronchial muscle constriction.
mucosal swelling/inflammation.
increased mucous production.
give 2 diseases associated with asthma
eczema, hay fever, any allergy - atopy
what is atopy?
ready development of IgE antibodies against common environmental antigens
explain the hygiene hypothesis
the idea that growing up in a clean environment may predispose towards IgE response, as there is no childhood exposure to allergens, bacteria etc
describe the pathology seen in the airways of someone with asthma
inflammation + remodelling:
increased inflammatory cells in bronchial wall, mucous membranes and secretions.
B cells producing IgE.
airway smooth muscle hypertrophy and hyperplasia. thickening of airway wall - smooth muscle + repair collagens.
loss of ciliated columnar cells into lumen + increase no. mucous secreting goblet cells in epithelium.
give 3 precipitants of an asthma attack
cold air, exercise, emotion, allergens, infection, smoking, pollution, NSAIDs, beta blockers
what investigations would you perform to diagnose asthma?
peak expiratory flow rate - diurnal variation, marked dip in PEFR in AM - variation of >15%.
also - increase in PEF/FEV1 ratio of >15% after salbutamol.
give the steps in the management of mild to severe asthma (BTS guidelines)
SILCO:
1. Short-acting beta2 agonist (SABA) e.g. salbutamol PRN
2. + Inhaled corticosteroid (e.g. beclamethasone) if using SABA >1/day
3. + LABA e.g. salmeterol
4. “Consider other options” = trial of leukotriene receptor agonist or oral theophylline
5. add Oral prednisolone, refer to asthma clinic
how would you control an acute asthma attack?
100% O2 with facemask.
nebulisers of salbutamol and ipatropium bromide.
IV hydrocortisone/prednisolone.
how to beta 2 agonists work?
activate beta 2 receptors, inducing smooth muscle relaxtion in lungs.
describe what is happening in the lungs of a patient with extrinsic allergic alveolitis (hypersensitivity pneumonitis)
inhalation of allergens provokes a hypersensitivity reaction, with complement activation, granuloma formation and obliterative bronchiolitis.
give 2 causes of EAA (hypersensitivity pneumonitis)
Farmer’s lung.
Bird-fancier’s lung - proteins in bird droppings.
Malt-worker’s lung.
Bagassosis/Sugar worker’s lung.
humidifier fever.
Mushroom workers.
Cheese washer’s lung.
Wine maker’s lung.
give 3 clinical features of EAA seen after exposure to the allergen
fevers, rigors, myalgia, dry cough, dyspnoea, crackles (no wheeze)
give 3 chronic features of EAA
increasing dyspnoea, weight loss, exertional dyspnoea, type I respiratory failure, cor pulmonale
what would been seen on CXR of a patient with EAA?
fibrosis/mottling of upper lobes and honeycomb lung
list some investigations that might be performed on a patient with EAA
bloods - neutrophilia, raised ESR
CXR.
lung function tests (reversible restrictive).
broncheoalveolar lavage.
how would you treat EAA in an acute and a chronic situation?
acute - remove allergen, give O2 + oral prednisolone.
chronic - avoid exposure (facemask), long-term steroids.
list 3 occupational lung diseases
EAA (e.g. Farmer’s lung).
Coal worker’s pneumonconiosis.
Silicosis.
Asbestosis.
Byssinosis.
Berylliosis.
what causes the fibrosis seen in coal worker’s pneumoconiosis?
inhalation of coal dust particles - ingested by macrophages - these die and release their enzymes - fibrosis
what would a CXR show in coal worker’s pneumoconiosis?
round opacities in upper zone.
what causes progressive massive fibrosis? what are the features of this?
progression of coal worker’s pneumoconiosis.
progressive dyspnoea, fibrosis + eventual cor pulmonale.
give some examples of jobs at risk of silicosis
metal mining, stone quarrying, sand blasting, pottery/ceramic manufacture
what do investigations show in silicosis?
CXR - diffuse miliary/nodular pattern in upper and mid-zones + egg shell calcification of hilar nodes.
Spirometry - restrictive.
what disease are patients with silicosis at greater risk of?
TB
what are the clinical features of asbestosis?
progressive dyspnoea.
O/E - clubbing, fine end-inspiratory crackles, pleural plaques.
what two diseases are asbestosis patients at greater risk of?
bronchial adenocarcinoma and mesothelioma
in what industries might workers get byssinosis? and for berylliosis?
byssinosis - cotton mill workers.
berylliosis - beryllium-copper alloy used in aerospace industry, electronics, atomic reactors.
describe the pathogenesis of bronchiectasis
chronic infection of bronchi/bronchioles leads to inflamed, thickened and irreversibly damaged walls with permanent dilation.
mucociliary transport mechanism is impaired.
give 2 of the main organisms involved in bronchiectasis
H influenza, Strep pneumonia, Staph aureus, Pseudomonas aeruginosa
give 3 possible causes of bronchiectasis
congenital - CF.
post-infection - measles, pertussis, pneumonia, TB, HIV.
Other - bronchial obstruction (tumour, foreign body), allergic bronchopulmonary aspergillosis (ABPA), hypogammaglobulinaemia, rheumatoid arthritis, UC.
give 3 clinical features of bronchiectasis
persistent cough, copious purulent sputum, intermittent haemoptysis, finger clubbing, coarse inspiratory crepitations, wheeze
give 2 possible complications of bronchiectasis
pneumonia, pleural effusion, pneumothorax, haemoptysis, cerebral abscess, amyloidosis
name 3 investigations you would carry out in bronchiectasis and their results
*sputum culture.
*CT scan - shows the dilated airways.
CXR - cystic shadows, thickened bronchial walls.
spirometry - obstructive pattern.
broncoscopy - locate site of haemoptysis, exclude obstruction, obtain samples.
how would you manage a patient with bronchiectasis?
physiotherapy - postural drainage.
Abx - flucloxacillin for staph, amoxicillin for strep, tazocin for pseudomonas.
bronchodilators - salbutamol nebulisers.
Oral/inhaled corticosteroids.
what causes cystic fibrosis?
autosomal recessive mutation in the CF transmembrane conductase regulator gene on chromsome 7.
defective chloride secretion and increased sodium absorption over airway epithelium - produces very viscous and sticky mucous.
give 3 respiratory symptoms of CF
cough, wheeze, recurrent infections, bronchiectasis, pneumothorax, haemoptysis, respiratory failure, cor pulmonale
give 3 extrapulmonary features of CF
pancreatic insufficiency - DM, steatorrhoea.
intestinal obstruction, gallstones, cirrhosis, male infertility, osteoporosis, arthritis, vasculitis, sinusitis.
name 3 investigations you would carry out in CF and their results
sweat test - increased sodium and chloride secretion in sweat.
faecal elastase - screens for pancreatic dysfunction.
genetic screening for CF mutations.
CXR - hyperinflation, bronchiectasis.
how would CF be managed?
physiotherapy.
Abx for exacerbations.
mucolytics - DNase (dornase alfa).
bronchodilators.
fat soluble vit supplements.
pancreatic enzyme replacement.
what is sarcoidosis? what genes is it associated with?
multisystem granulomatous disorder of unknown cause.
associated with HLA-DRB1 and DQB1 alleles.
what is seen on transbronchial biopsy in sarcoidosis?
infiltration of alveolar walls and interstitial spaces with mononuclear cells - later, granulomas
how does acute sarcoidosis present?
erythema nodosum ± polyarthralgia
give 3 pulmonary features of sarcoidosis?
dry cough, progressive dyspnoea, decreased exercise tolerance, chest pain.
give 3 extra-pulmonary features of sarcoidosis
lymphadenopathy, hepatomegaly, splenomegaly, uveitis, conjunctivitis, glaucoma, Bell’s palsy, neuropathy, meningitis, brainstem and spinal syndromes, space occupying lesions, erythema nodosum, cardiomyopathy, arrhythmias, hypercalcaemia, renal stones, pituitary dysfunction
what are the features of sarcoidosis on CXR?
bilateral hilar lymphadenopathy ± pulmonary infiltrates/fibrosis
list some differential diagnoses for bilateral hilar lymphadenopathy
sarcoidosis, infection (TB, mycoplasma), malignancies, silicosis, EAA
what investigations would you carry out, apart from CXR, in sarcoidosis, and what might they show?
SERUM ACE is raised.
lung function - restrictive pattern, reduced TLC, reduced FEV1/FVC ratio.
tissue biopsy - non-caseating granuloma.
how would you treat sarcoidosis?
if symptomatic - corticosteroids (prednisolone).
if severe - IV methylprednisolone or methotrexate.
what is the underlying pathology of idiopathic pulmonary fibrosis?
disruption of alveolar epithelium and basement membrane activates inflammation.
fibroblasts convert to myofibroblasts - synthesise collagen and aggregate to form fibrotic foci.
give 3 symptoms and 3 signs of idiopathic pulmonary fibrosis
symptoms - dry cough, exertional dyspnoea, malaise, weight loss, arthralgia.
signs - cyanosis, finger clubbing, fine end-inspiratory crepitations.
what investigations would you carry out in idiopathic pulmonary fibrosis? what do they show? which one is needed for diagnosis?
CXR - ground glass appearance, decreased lung volume, bilateral lower zone reticulo-nodular shadows - honeycombing if severe.
lung function tests - restrictive pattern, increased FEV1/FVC ratio.
need a lung biopsy.
what is the ultimate end treatment of idiopathic pulmonary fibrosis?
lung transplant
name 3 causes of pulmonary hypertension
hereditary, SLE, systemic sclerosis, rheumatoid arthritis, drugs, HIV, portal hypertension, schistosomiasis, chronic haemolytic anaemia, COPD, pulmonary fibrosis, mitral valve disease, sarcoidosis
define pulmonary hypertension
elevated pulmonary artery pressure (>25mmHg at rest) and secondary right ventricular failure
give 3 clinical features of pulmonary hypertension
exertional dyspnoea, lethary, peripheral oedema, loud pulmonary second sound, right parasternal heave
give 3 signs that pulmonary hypertension has progressed to right heart failure (cor pulmonale)
elevated JVP, hepatomegaly, pulsatile liver, peripheral oedema, ascites, pleural effusion
what is the eventual end treatment of primary pulmonary hypertension?
heart and lung transplant