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
Management of cystic fibrosis
- Stop smoking
- Flu vaccine
- Exercise = improves resp function and helps clear sputum
- High calorie diet and high fat intake = malabsorption and increased demand
- Fat soluble vitamin supplements (ADEK)
- CREON tablets to replace lipase
- Chest physiotherapy = postural drainage, airway clearance techniques
- Abx = acute infective exacerbations and prophylactically
o Flucloxacillin = staph. Aureus
o Amoxycillin = haemophilus influenzae - Mucolytics (nebulised dornase alfa)
- B2 agonists (salbutamol) and inhaled corticosteroids (beclomethasone)
- Amiloride = inhibits Na+ transport less mucus
- Pancreatic enzyme replacement (CREON tablets)
- Ursodeoxycholic acid for impaired liver function
- Liver transplant (Cirrhosis)
- Treatment of CF-related diabetes
- Screening/Tx for osteoporosis = DEXA bone scanning
- Fertility and genetics counselling
- Advanced disease = oxygen, diuretics, non-invasive ventilation, lung/heart transplant
- Minimise contact with other CF patients
Complications of cystic fibrosis
- Recurrent infections
- Pulmonary Bronchiectasis, Pneumothorax, Respiratory failure
- Cor pulmonale
- GI pancreatic insufficiency, distal intestinal obstruction syndrome, gallstones, cirrhosis, liver failure
- Male infertility congenital bilateral absence of vas deferences
- Osteoporosis
- Arthritis
- Vasculitis
- Nasal polyps
- Sinusitis
- Hypertrophic pulmonary osteoarthropathy
- Diabetes
- Vitamin D deficiency
Causes of lung cancer
- Cigarette smoking (including passive)
- Occupational = Asbestos, Coal and products of coal combustion (tar), Chromium, Arsenic, Nickel, Petroleum products, Iron oxide
- Environmental = Radon exposure, Ionising radiation
- Host factors = pulmonary fibrosis, HIV infection
Types of lung cancer
- Small cell lung carcinoma (cigarette smoking)
o Often arises in central bronchus from endocrine cells
o Secretes polypeptide hormones
o Early development of widespread metastases - Non-small cell lung carcinoma
o Squamous cell carcinoma (cigarette smoking)
o Tumours centrally and frequently cavitate with central necrosis
o Arise from epithelial cells associated with production of keratin
o Cause obstructive lesions of bronchus with post-obstructive infection
o Local spread common - Adenocarcinoma (asbestos/non-smokers)
o Central or peripheral
o Usually single lesions but can arise in multifocal pattern (can be bilateral)
o Originate from mucus-secreting glandular cells
o Metastases common - Carcinoid tumours
- Lymphomas
- Benign tumour
Metastases of lung cancer
liver, bone, adrenal glands, brain
Presentation of lung cancer
- Cough and haemoptysis
- Breathlessness
- Chest pain
- Wheeze
- Recurrent infections (pneumonia)
- Weight loss
- Metastatic disease = Bone pain, Headache, Seizures, Neurological deficit, Hepatic pain, Abdominal pain
- Finger clubbing squamous cell
- Lymphadenopathy
- Gynaecomastia adenocarcinoma
Investigations of lung cancer
- CXR Hilar enlargement, Consolidation, Lung collapse, Pleural effusion (unilateral)
- CT contrast of chest, abdo, pelvis for staging
- PET CT
- Bronchoscopy with endobronchial ultrasound + biopsy
- Cytology = Sputum and pleural fluid
- FBC down
TNM classification of lung cancer
- Tumour
o T1 <3cm
o T2 >3cm
o T3 = invades chest wall, diaphragm and pericardium
o T4 = invades mediastinum, heart, great vessels, trachea, oesophagus, vertebra, carina, malignant effusion, metastases in same lobe - Nodes
o N0 = no nodes
o N1 = hilar nodes
o N2 = same side mediastinal nodes/subcarinal
o N3 = contralateral mediastinum/supraclavicular - Metastasis
o M1a = tumour on same side
o M1b = tumour elsewhere
Management of lung cancer
- Non-small cell lobectomy, RT, chemo
- Small cell (worse prognosis) Chemotherapy and radiotherapy,
- Endobronchial treatment with stents/debulking = palliative
- Pleural drainage for symptom relief
- Medications = Analgesia, steroids, antiemetics, bronchodilators, antidepressants
- Surgery lobectomy, pneumonectomy
Contraindications for surgery in lung cancer
o Stage IIIb or IV
o FEV1<1.5L
o Malignant pleural effusion
o Tumour near hilum
o Vocal cord paralysis
o SVC obstruction
Complications of lung cancer
- Recurrent laryngeal nerve palsy (hoarse voice)
- Phrenic nerve palsy (shortness of breath)
- Superior vena cava obstruction (facial swelling, difficulty breathing, distended veins in neck and upper chest)
- Horner’s syndrome
- Syndrome of inappropriate ADH (hyponatraemia)
- Cushing’s syndrome
- Hypercalcaemia
- Limbic encephalitis
- Lambert-Eaton myasthenic syndrome
Other cancers that metastasise to lung
Breast, Colorectal, Renal cell, Bladder, Prostate
Classification of pneumonia
- Community-acquired pneumonia (CAP) Occurs across all ages but commoner in extremes of age
- Hospital-acquired pneumonia (HAP) Patients >48 hrs of initial admission or healthcare setting within last 3 months
o Mostly elderly, ventilator-associated and post-operative
Risk factors for pneumonia
- Co-morbidities = HIV, DM, CF, COPD, bronchiectasis
- Smoking
- Excess alcohol
- IVDU
- Immunosuppressant therapy
Risk factors for aspiration pneumonia
o Poor dental hygiene
o Swallowing difficulties
o Prolonged hospitalisation or surgical procedures
o Impaired consciousness
o Impaired mucociliary clearance
