Respiratory Flashcards
Risk factors for asthma?
Genetic: atrophy
Environmental: allergens, hygiene hypothesis, adult-onset (e.g. occupational)
What is asthma?
Allergic airway problem causing airway obstruction
Asthma triggers?
Aeroallergens Exercise Anxiety/stress Temperature changes Cigarette smoke Foods, additives Occupational agents e.g. isocyanates Drugs: NSAIDs, b-blockers
What predisposes people to getting asthma?
Airway hyperresponsiveness
Sensitisation to house dust mites
Female
Smoking at age 21
Obstructive spirometry?
FEV1 < 80% predicted
FVC normal/low
FEV1/FVC < 70%
How to investigate asthma?
Spirometry Peak flow Reversibility testing Chest x-ray Blood eosinophils IgE Skin prick tests
What is a positive reversibility test result for asthma?
> 400 ml improvement or symptom scores
How to diagnose asthma?
Clinical diagnosis based on presence of symptoms (dyspnoea, cough, wheeze)
Supported by evidence from investigations
Features supportive of an asthma diagnosis?
Wheeze Dyspnoea Chest tightness Especially after a trigger Widespread wheeze on auscultation Unexplained low FEV1 or PEF
Factors that don’t support an asthma diagnosis?
Dizziness, light-headedness, peripheral tingling -> hyperventilation
Chronic productive cough without wheeze or dyspnoea -> COPD, bronchiectasis, chronic cough syndrome
Repeatedly normal examination when symptomatic
Vocal disturbance -> vocal cord dysfunction
Symptoms only with colds -> bronchial hyper-reactivity syndrome
> 20 pack year SHx -> COPD
Cardiac disease
Normal PEF/spirometry when symptomatic
What to do if you suspect asthma?
Trial asthma treatment
If successful: continue
If not successful: assess inhaler technique and compliance
If no further improvement: consider other causes, referral
Non-pharmacological management of asthma?
Avoid triggers
Pharmacological management of asthma?
Stepwise approach 1. Low dose ICS and SABA PRN 2. Add inhaled LABA 3. Can stop LABA if no response Can increase ICS dose Can add in a trial therapy 4. High dose ICS Can add in a fourth drug e.g. LAMA Referral 5. Daily steroid tablet High dose ICS Referral
Name some SABAs?
Salbutamol
Terbutaline
What treatments can you consider in severe asthma clinics?
High dose ICS Tiotropium Immunosuppressants Macrolide antibiotics Biologics e.g. anti IgE (omalizumab), anti IL-5 (mepolizumab)
Asthma add on therapies?
LABA + ICS e.g. Foster Leukotriene receptor antagonists Theophylline Higher dose ICS Oral steroids
What is the main cause of acute asthma exacerbations?
Viral URTI
How to manage acute asthma exacerbations?
ABCDE
High flow O2 -> aim for sats 94%
Salbutamol MDI + spacer or O2 driven nebuliser
Add ipratropium if no response (SAMA)
Engage critical care team if very severe
Prednisolone 40 mg for 5 days to reduce chance of recurrence
How to prevent acute asthma exacerbations?
Asthma management plan
Annual review
Identify the at risk patients
What is COPD?
Inflammatory airway problem causing chronic airway obstruction
Environment risk factors for COPD?
Cigarette smoking Environmental tobacco smoke Occupation: dust, chemicals Indoor and outdoor pollution Infections Socio-economic status
Host risk factors for COPD?
Genes- alpha-1 antitrypsin deficiency
Hyper-responsiveness
Poor lung growth
Increasing age
Pathology of COPD?
Inflammatory airway problem causes small airway narrowing and alveolar destruction
Triad of COPD pathological changes?
Bronchial gland enlargement
Emphysema
Bronchiolitis
What is chronic bronchitis?
Hyperplasia of goblet cells -> hypersecretion of mucus
Cough productive of sputum on most days for 3 months over 2 consecutive years
What is emphysema?
Abnormal, permanent enlargement of airspaces distal to the terminal bronchioles and destruction of their walls without obvious fibrosis
Types of emphysema?
Centrilobular emphysema: common in smokers
Pan-lobular emphysema: common in alpha-1 antitrypsin deficiency
COPD symptoms?
Dyspnoea
Chronic cough
Chronic sputum production
Physical examination of COPD?
Tachpnoea Accessory muscle use Pursed lip breathing Hyper-inflation: this makes it hard to localise the apex beat Hoover's sign Reduced breath sounds Wheeze Respiratory crackles Central cyanosis Flapping tremor Peripheral oedema Weight loss/loss of muscle mass
Common triggers of COPD exacerbations?
Bacteria
Virus
Pollutants
Investigations for COPD?
Modified MRC questionnaire (mMRC)
COPD assessment test (CAT)
Spirometry
Chest x-ray
Lung volume and diffusing capacity (severity)
Oximetry and ABG
Genetic screening if < 45 years or strong FHx
What is the reversibility testing result in COPD?
> 200 ml and 12% of pre-drug value
If > 400 ml -> think asthma
How to assess severity in COPD?
Post-bronchodilator FEV1
GOLD ABCD assessment
Post-bronchodilator FEV1 severity in COPD?
Stage I (mild): FEV1 ≥ 80% predicted Stage II (moderate): FEV1 50-79% predicted Stage III (severe): FEV1 30-49% predicted Stage IV (very severe): FEV1 < 30% predicted or < 50% with respiratory failure
GOLD ABCD severity assessment for COPD?
A: low risk, less symptoms
B: low risk, more symptoms
C: high risk, less symptoms
D: high risk, more symptoms
COPD management?
Reduce risk factors
Smoking cessation
Pulmonary rehabilitation
SABA or LABA
Bronchodilators dependent on GOLD severity
Nebuliser: consider if FEV1 < 50% post bronchodilator or very symptomatic
COPD drug management based on GOLD severity?
A: Bronchodilator B: LABA or LAMA Then LABA + LAMA C: LAMA Then LAMA + LABA OR LABA + ICS D: LAMA OR LAMA + LABA OR LAMA + ICS Then LAMA + LABA + ICS Then Roflumilast (FEV1 < 50%) or macrolide (former smoker)
COPD exacerbation management?
Optimise bronchodilators Use a nebuliser Antibiotics Short course of oral corticosteroids Treat respiratory failure if present Oxygen Ventilation if needed
How to treat Type 1 respiratory failure?
Controlled oxygen
How to treat Type 2 respiratory failure?
Controlled oxygen Nebulisers Antibiotics Oral corticosteroids Monitor
What is bronchiectasis?
Chronic inflammation of the bronchi and bronchioles -> permanent dilation and thinning of the airways
Causes of bronchiectasis?
Congenital: cystic fibrosis, Young’s syndrome, primary ciliary dyskinesia, Kartagener’s syndrome
Post-infective: measles, pertussis, bronchiolitis, pneumonia, TB, HIV
Other: bronchial obstruction, allergic bronchopulmonary aspergillosis, hypogamaglobulinaemia, RA, UC
Idiopathic
Common presentation of bronchiectasis?
Recurrent pulmonary infections
Bronchiectasis symptoms?
Persistent cough
Copious purulent sputum
Intermittent haemoptysis
Bronchiectasis signs?
Finger clubbing
Course inspiratory crackles
Crackles often clear after coughing
Wheeze
Complications of bronchiectasis?
Pneumonia Pleural effusions Pneumothorax Haemoptysis Cerebral abscess Amyloidosis
Investigations for bronchiectasis?
Sputum culture Chest x-ray CT scan Spirometry: obstructive pattern Bronchoscopy Serum immunoglobulin CF sweat test Aspegillus precipitants or skin prick test RAST and total IgE
Bronchiectasis signs on chest x-ray?
Tramline and ring shadows
Thickened bronchial walls
Cystic shadows
Bronchiectasis signs on CT?
Signet ring sign
Types of pulmonary TB?
Active infection
Latent infection
When is TB transmissible?
From a person with an active infection
Clinical features of TB?
Low-grade fever Anorexia Weight loss Malaise Night sweats Pleuritic pain Clubbing (due to bronchiectasis) Erythma nodosum
Clinical features of pulmonary TB?
Cough: dry then productive Pleurisy Haemoptysis Pleural effusion Aspergilloma/mycetoma may form in cavities Asymptomatic or atypical presentation
Investigations for active TB?
Chest x-ray Sputum acid-fast bacilli (AFB) smear Sputum culture FBC Nucleic acid amplification test (NAAT)
Investigations for latent TB?
Tuberculin skin test (TST)
Interferon-gamma release test (IGRAS)
Treatment of active TB?
Notify local public health protection
NAAT for drug resistance
Antibiotics
What are the antibiotics used in TB?
Rifampicin
Isoniazid
Pyrazinamide
Ethambutol
What lung diseases can Aspergillus cause?
Asthma
Allergic bronchopulmonary aspergillosis (ABPA)
Aspergilloma (mycetoma)
Extrinsic allergic alveolitis
What does ABPA stand for?
Allergic bronchopulmonary aspergillosis
What is the pathology of ABPA?
Type I and III hypersensitivity reactions to Aspergillus -> bronchoconstriction then permanent damage (bronchiectasis)
Clinical features of ABPA?
Wheeze Cough Sputum Mucus plugs containing fungal hyphae Dyspnoea Recurrent pneumonia
Investigations for ABPA?
Chest x-ray Sputum contains Aspergillus Positive skin test Aspergillus specific IgE RAST Positive serum precipitants Eosinophilia Raised serum IgE
Management of ABPA?
Prednisolone
Antifungal
Bronchodilators
Bronchoscopic aspire for mucus plugs
What is aspergilloma?
A fungus ball in a pre-existing cavity e.g. from TB or sarcoidosis
Clinical features of aspergilloma?
Usually asymptomatic Cough Haemoptysis Lethargy Weight loss
Investigations for aspergilloma?
Chest x-ray
Sputum culture
Aspergillus skin test
Management for aspergilloma?
Only if symptomatic
Surgical excision for solitary symptomatic lesions or severe haemoptysis
Investigations for invasive aspergillosis?
Sputum culture BAL Biopsy -> diagnostic Serum precipitants Chest x-ray Early chest CT Serial measurements of galactomannan
Treatment of invasive aspergillosis?
Antifungals e.g. voriconazole
What is extrinsic allergic alveolitis?
Hypersensitivity reaction to inhaled fungal spores in sensitised individuals
Acute clinical features of extrinsic allergic alveolitis?
Fever Rigors Myalgia Dry cough Dyspnoea Fine bibasal crackles
Chronic clinical features of extrinsic allergic alveolitis?
Finger clubbing Increasing and exertion dyspnoea Weight loss Type 1 respiratory failure Cor pulmonale
Investigations for extrinsic allergic alveolitis?
Bloods: FBC, ESR, serum antibodies ABG Chest x-ray Spirometry: restrictive disease (is reversible at first) BAL (for chronic disease) CT chest (for chronic disease)
Management of extrinsic allergic alveolitis?
Acute: remove allergen, oxygen, prednisolone
Chronic: allergen avoidance, long-term steroids
Can get compensation for some causes
Risk factors for bronchial carcinoma?
Cigarette smoking Passive smoking Asbestos Chromium Arsenic Iron oxides Radiation
Types of bronchial carcinoma?
Small cell: 15-20%
Non-small cell: > 80%
Types of non-small cell lung cancer?
Adenocarcinoma
Squamous cell carcinoma
Large cell carcinoma