Respiratory Flashcards
What are the differentials for cough?
Acute - pneumonia, LRTI, bordetella pertussis, infection
Chronic - post-infective, asthma, COPD, bronchiectasis, cystic fibrosis, TB, lung cancer
Other - allergies, cold air, foreign body, GORD
ACEi, heart failure
Differentials for haemoptysis
- Vasculitis
- Acute/chronic bronchitis
- Pulmonary TB
- Lung abscess
- Pneumonia
- Bronchiectasis
- Foreign body
- Anticoagulant
- Primary lung cancer
- Lung mets
Pulmonary differentials for dyspnoea
Pulmonary embolism
Pneumonia
Pneumothorax
Asthma exacerbation
COPD exacerbation
Pleural effusion
Lung cancer
Interstitial lung disease
Pulmonary differentials for chest pain
- Pneumothorax
- Pulmonary embolism
- Pneumonia
What is asthma?
Chronic inflammatory condition of airways that causes episodic exacerbations of bronchoconstriction
Risk factors for asthma
- Personal history of atopy eczema, hayfever, food allergies
- Family history of asthma/atopy
- Obesity
- Inner-city environment
- Premature birth and associated LBW
- Socio-economic deprivation
- Respiratory infections in infancy
- Exposure to tobacco smoke/inhaled particulates
Triggers for asthma
- Viral respiratory infection
- Night time or early morning
- Exercise
- Allergen or irritant exposure: animals, dust
- Changes in weather: Cold/damp
- Strong emotions/ laughter
- NSAIDs/ BB
Presentation of asthma
- Intermittent dyspnoea
- Dry cough (esp nocturnal)
- Tight chest
- Sx worse at night/early morning
- Bilateral widespread ‘polyphonic’ wheeze
Red Flags for asthma
- Failure to thrive
- Unexplained clinical findings (focal signs, abnormal voice/cry, dysphagia, inspiratory stridor)
- Symptoms present from birth
- Excessive vomiting or posseting
- Evidence of severe upper RTI
- Persistent wet or productive cough
- FHx of unusual chest disease
- Nasal polyps
Investigations for asthma
- Spirometry with bronchodilator reversibility
- FEV1/FVC <70% indicates airway obstruction
- Improvement in FEV1 with bronchodilator >12% is positive - Fractional exhaled nitric oxide (all patients aged >17)
- 35 ppb or higher with positive peak flow variability and obstructive spirometry with positive bronchodilator reversibility
- FeNO test for children 5-16 if normal spirometry or obstructive spirometry with negative bronchodilator reversibility - peak flow variability with diary for 2 weeks
- >15% improvement in FEV1/PEFR following inhalation of bronchodilator
Medical management of asthma
- Short-acting beta 2 agonist inhaler (salbutamol)
- Low dose inhaled corticosteroid (prednisolone/ beclomethasone)
o Used inhaled SABA 3x a week or more
o Asthma Sx 3x a week or more
o Woken at night by asthma Sx once weekly or more - Long acting beta 2 agonist (salmeterol)
- Increase dose of ICS
- Leukotriene receptor antagonist (montelukast)
- Inhaled long acting muscarinic antagonists (tiotropium)
- Oral theophylline
- Add oral corticosteroid
Complications of asthma
- Pneumonia
- Pulmonary collapse
- Impaired QoL = fatigue, underperformance at school
- Steroid use = oral/oesophageal candida, iatrogenic Cushing’s
- Status asthmaticus = Life-threatening exacerbation
What is COPD?
Non-reversible long-term deterioration in airflow through lungs caused by damage to lung tissue involving airway obstruction, chronic bronchitis and emphysema
What can cause COPD?
- Cigarette smoking
- Chronic exposure to pollutants at work mining, building and chemical industries
- Outdoor air pollution
- Inhalation of smoke from biomass fuels (heating/cooking in poorly ventilated areas)
How does COPD present?
- Productive cough with white or clear sputum
- Wheeze
- Breathlessness
- Sx worsened by cold or damp weather and atmospheric pollution
- Depression
- Weight loss
- Hypertension
- Reduced muscle mass with general weakness
- Prolonged expiration
- Chest expansion poor
- Lungs hyper inflated = barrel chest
- Pursed lips on expiration = help prevent alveolar and airway collapse
What is shown on spirometry in COPD?
o FEV <80% predicted
o FEV1/FVC <0.7 = airway obstruction
o Multiple peak flow measurements to exclude asthma
What is shown on CXR in COPD?
o normal/hyper inflated lungs
o long narrow heart shadow
o reduced peripheral lung marking and bullae
o Flattened hemidiaphragms
What is the MRC dyspnoea scale for COPD?
- Not troubled by breathless except on strenuous exercise
- SoB when hurrying on a level or when walking up slight hill
- Walks slower than most people on level, stops after mile or so, stops after 15 mins walking at own pace
- Stops for breath after walking 100 yards or after few mins of level ground
- Too breathless to leave house or breathless when dressing/undressing
Medical management of COPD
- 1st line = SABA (salbutamol) or short acting antimuscarinics (ipratropium bromide)
- 2nd line (not asthmatic/steroid responsive) = LABA plus LAMA combination inhaler
o If already taking SAMA, discontinue and switch to SABA - 2nd line (asthmatic/steroid responsive) = LABA plus inhaled corticosteroid combination inhaler
o If patients remain breathless or have exacerbations offer triple therapy (LAMA + LABA + ICS) - Oral theophylline after trials of short and long-acting bronchodilators and those who cannot use inhaled therapy
Features suggesting steroid responsiveness
previous diagnosis of asthma or atopy
a higher blood eosinophil count
substantial variation in FEV1 over time (at least 400 ml)
substantial diurnal variation in peak expiratory flow (at least 20%)
Complications of COPD
- Osteoporosis
- Cor pulmonale
- Respiratory failure (later stages) = PaO2 <8kPa or PaCO2 >7kPa
- Pulmonary hypertension (advanced disease) fluid retention, peripheral oedema, centrally cyanosed
- Recurrent respiratory infections (H. influenzae)
What is cystic fibrosis?
Autosomal recessive genetic condition affecting mucus glands
Presentation of cystic fibrosis
- Neonates = Failure to thrive, Meconium ileus (bowel obstruction due to thick meconium), Rectal prolapse
- Resp = dyspnoea, Chronic cough, Thick sputum production, Recurrent respiratory tract infections
- Abdo = Steatorrhoea, Abdominal pain and distension
- Salty sweat
- Cyanosis
- Finger clubbing
- Bronchial breath sounds = harsh breath sounds equally loud on inspiration and expiration
- Bilateral coarse crackles = air passing through sputum in airways
- Dullness to percussion = lung tissue collapse/consolidation
- Nasal polyps
- Low weight or height on growth charts
Investigations of cystic fibrosis
- Newborn blood spot testing
- Sweat test = High sodium and chloride conc >60mmol/L
- Genetic screening for known CFTR mutations
- Faecal elastase test = Low or no levels of elastase in CF (mucus blocking release)
- Blood: FBC, U&Es, LFT, clotting, vit ADE levels, annual glucose tolerance test
- Bacteriology = cough swab, sputum culture
- CXR = hyperinflation, bronchiectasis
- Abdo USS = fatty liver, cirrhosis, chronic pancreatitis
- Spirometry = obstructive defect
- Biochemistry = faecal fat analysis