Airways disease Flashcards
Asthma symptoms?
SOB
Chest tightness
Cough
Expiratory wheeze
Triggers for asthma symptoms?
Allergen exposure
Cold
Smoke
What is asthma?
Chronic inflammation of airways characterised by intermittent obstruction and hyper-reactivity
Inflammatory reaction type in asthma?
Th2 response - characterised by CD4+ cells
What do CD4+ cells secrete?
IL4, IL5, IL13 and TNFa
What does IL-4 do?
Stimulates B lymphocytes - IgE production - mast cell degranulation - histamine release
What does IL-5 do?
Stimulate eosinophils
What does IL-13 do?
Stimulate mucus production
What does IL-1 do?
Acute inflammation and fever
What is the anti-inflammatory cytokine
IL-10 - inhibits IL-1
What does IL-2 do?
Activation and proliferation of T cells
What does TNFa do?
Fever + attract neutrophils
Investigations for asthma?
Spirometry Peak flow CXR Exhaled NO Sputum eosinophilia
What would spirometry results be for asthma?
Obstructive pattern - FEV1/FVC <80%, FEV1 should drop by at least 20%, FVC would be normal
Classification of asthma?
Mild intermittent
Mild persistent
Moderate persistent
Severe persistent
Mild intermittent asthma?
Symptoms less than twice a week
Mild persistent asthma?
Symptoms more than twice a week but less than once a day
Moderate persistent asthma?
Daily symptoms +use of SABA
Severe persistent?
Continuous symptoms, frequent exacerbations, limited physical activity
Step one of asthma control?
SABA - salbutamol
Step two of asthma control?
SABA + low dose inhaled corticosteroid
Step three of asthma control?
SABA + ICS + LABA - salmeterol
Step four of asthma control?
SABA + ICS + LABA + theophylline or monteleukast or up steroid dose
Step five of asthma control?
SABA + med dose ICS + LABA + theo/monte + oral steroid or high dose ICS
Treatment for asthma exacerbation?
Oxygen Salbutamol Ipratropium Hydrocortisone Magnesium sulfate Theophylline Salbutamol IV
Peak of action of salbutamol?
15 minutes
Asthma vs COPD?
Reversibility in asthma non in COPD
What is theophylline?
Phosphodiesterase inhibitor
What is monteleukast?
Leukotriene receptor antagonist
Causes of COPD?
GASES Genetic - alpha-1 antitrypsin deficiency Air pollution Smoking Exposure through occupation Second-hand smoke exposure
What is alpha-1 antitrypsin?
A proteinase inhibitor produced in the liver which inhibits enzymes such as neutrophil elastase which breaks down alveolar wall connective tissue
What does GOLD assess?
Severity of airflow limitation and exacerbation history
GOLD stage 1?
Mild COPD - FEV1 >80% of predicted
GOLD stage 2?
Moderate COPD - FEV1 <80% of predicted
GOLD stage 3?
Severe COPD - FEV1 <50% of predicted
GOLD stage 4?
Very severe COPD - FEV1 <30% of predicted
How is exacerbation/risk assessed?
Number of exacerbations requiring steroids + hospital admissions and CAT score - COPD assessment test
Complications of COPD?
CLIPPR Cor pulmonale Lung cancer Infection Pneumothorax Polycythaemia Respiratory failure
What is bronchiectasis?
Permanent dilation of bronchi due to the destruction of the bronchial wall
Why does bronchiectasis occur?
Most commonly - recurrent infections or secondary to HIV, cystic fibrosis, ciliary dyskinesia, or alpha-1 antitrypsin deficiency
CT findings in bronchiectasis?
Thickened, dilated airways w or w/out fluid levels, varicose constrictions, cysts
Symptoms of bronchiectasis?
Purulent sputum Persistent cough Fever Clubbing Crepitations Coarse inspiratory crackles
Complications of bronchiectasis
Massive haemoptysis
What is Kartagener’s syndrome
Cilia become immobile
What is type 1 respiratory failure?
<8kPa PaO2 with normal or low CO2 - Damage to lung tissue - V/Q mismatch in part of the lung
Why do they not get hypercapnic in type 1 respiratory failure?
Less lung tissue is required to excrete CO2 than oxygenate the blood
Causes of type 1 respiratory failure?
Pneumonia PE Pulmonary oedema Fibrosing alveolitis Acute asthma
Symptoms of respiratory failure
Agitation
Breathlessness
Confusion
Drowsiness+fatigue
What is type 2 respiratory failure?
<8kPa PaO2 + >6.7kPa PaCO2 - ventilatory failure due to reduced effort or increased resistance
Causes of type 2 respiratory failure?
COPD Cerebrovascular disease Opiate/benzos Myasthenia gravis Motor neuron disease
Complications of respiratory failure?
Infection
Heart failure
Arrhythmia
Pericarditis
Treatment of respiratory failure
Oxygen replacement therapy
Non invasive ventilation
Treat underlying cause
What is obstructive sleep apnoea?
Intermittent closure/collapse of pharyngeal airway causing apnoeic episodes during sleep
Risk factors for OSA?
Obesity Male Older age Opiate/benzo use Neurological disorders Increased soft tissue around airway Structurally narrow airway
What stage of sleep does OSA effect?
REM
Symptoms of OSA?
Snoring Restless sleep Morning headache Episodic gasping Apnoea episodes Decreased libido Poor cognitive performance
What questionnaire for OSA?
Epworth sleepiness score
How does modafinil work?
Dopamine reuptake inhibitor - reduces sleepiness
Treatment of OSA?
Weight reduction
CPAP
Modafinil
Most common pathogen found in bronchiectasis patients
Haemophilus influenza
Causes of restrictive lung disease?
Interstitial lung disease, sarcoidosis, obesity, scoliosis, neuromuscular disease
Upper zone pulmonary fibrosis causes?
TOP of the CHARTS
Coal workers pneumoconiosis
Hypersensitivity pneumonitis + Histiocytosis
Ankylosing spondylitis + Allergic bronchopulmonary aspergillosis
Radiation
Tuberculosis
Silicosis + Sarcoidosis
Lower zone fibrosis causes?
ACID = LOW pH Asbestosis Connective tissue disorders Idiopathic fibrosis Drug induced = amiodarone, methotrexate
Fibrosis symptoms?
Exertional dyspnoea Cough Chest tightness Wheeze Cyanosis Barrel chest Clubbing
What is pneumoconiosis?
Chronic lung disease caused by exposure to a dust or metal
Main types of pneumoconiosis?
Silicosis, berylliosis, coal miners, asbestosis
What is silicosis?
Exposure to silica, triggers macrophage fibrogenic response, can lead to TB
What is coal miner lung?
Exposure to coal dust, macrophage activation and fibrogenic response
What is berylliosis?
Exposure to beryllium, binds to T cells and alters their interactions
What is caplan’s syndrome?
Pneumoconiosis + rheumatoid = big nodules
What is asbestosis?
Exposure to asbestos fibres, damage through macrophage activation, associated with plural plaques, pleural thickening and pleural effusions
Risk factors for idiopathic pulmonary fibrosis?
Cigarette smoking Dust exposure GORD Diabetes Infection
Symptoms of IPF?
Exertional dyspnoea Cough Crackles Weight loss Fatigue Clubbing
Investigations in IPF?
CXR
HR-CT
PFT
CXR findings in IPF?
Basilar, peripheral, bilateral, asymmetrical, reticular opacities
HRCT findings in IPF?
Sub-pleural, basilar predominant reticular abnormalities
Honeycombing
Traction bronchiectasis
Ground glass opacities present but not extensive
HRCT findings that would doubt IPF diagnosis?
Upper/mid lung predominance Peribronchovascular dominance Extensive ground glass opacities Micronodules Cysts Air trapping Consolidation
If diagnosis of IPF cannot be made from history and imaging?
Bronchoalveolar lavage
Biopsy
Treatment of IPF?
Pirfenidone Nintedanib Pulmonary rehabilitation Oxygen therapy Smoking cessation Lung transplant
What is pirfenidone?
Inhibits collagen synthesis
Down regulates profibrotic cytokines
Decreases fibroblast proliferation
What is nintedanib?
Tyrosine kinase receptor blocker
What is transfer factor?
Describes rate at which a gas with diffuse from alveoli to blood
Causes of raised total gas transfer?
Asthma Pulmonary haemorrhage L-R cardiac shunts Polycythemia Hyperkinetic states Male gender Exercise
Causes of low total gas transfer?
Pulmonary fibrosis Pneumonia PE Pulmonary oedema Emphysema Low cardiac output Anaemia
What is KCO?
Transfer coefficient - rate of gas transfer corrected for lung volume
Increases with age
Increased KCO with normal total gas transfer?
Neuromuscular weakness
Scoliosis/kyphosis
Ankylosing spondylitis
Pneumonectomy/lobectomy
