Respiratory Flashcards
Definition of COPD
Persistent airflow limitation
FER = FEV1/FEC < 0.70 + symptomatic
Triggers of acute exacerbation of COPD
70% triggered by infection (viral and bacterial)
30% no clear aetiology i.e. “non-infective” –> environmental, PE, AMI
Symptom reduction pharmacotherapy of COPD
First line: monotherapy with LAMA > LABA
Second line: combination therapy with LAMA/LABA
Exacerbation prevention pharmacotherapy of COPD
First line: ICS/LABA or LAMA/LABA
Indications of ICS in COPD
- History of hospitalisations for exacerbations
- > / 2 moderate exacerbations of COPD per year
- Blood eosinophils >/ 300 cells/uL
- History of concurrent asthma
Triple therapy options for COPD
Fixed triple therapy treatment
- Fluticasone/Vilanterol/Umeclidinium (daily breath activated)
- Beclomethasone/Formoterol/Glycopyrronium (twice daily MDI)
Open triple therapy
- ICS + LABA + LAMA (generally 2 inhalers)
Non-pharmacological management of COPD
Pulmonary rehab
Smoking cessation
Pharmacotherapy for smoking cessation
Buproprion
Varenicline
NRT
Contraindications for bupropion
Should not be used in patients with history of bipolar disease
Contraindications for NRT
Should be avoided in unstable angina, recent MI, stroke or severe arrhythmias
Contraindications of varenicline
Should not be used in patients with unstable psychiatric symptoms or history of suicidal ideation
Definition of asthma
History of respiratory symptoms (i.e. wheeze, SOB, chest tightness and cough varying over time and intensity) with variable expiratory airflow limitation
Clinical features of asthma
Episodic symptoms
Atopy
Triggers
Work-related exposures
Asthma symptoms in childhood
Triggers of asthma
Smoking
Dust mite
Air pollutions
Moulds, pets, cockroaches
Viral illness
Workplace exposure
GORD
Role of FeNO in asthma
Measure of NO exhaled in breath
Low FeNO can be helpful when reviewing patients who take puffer therapies - proves compliance and response to treatment
Seen in non-eosinophilic asthma
Role of methacholine bronchoprovocation test
Negative test excludes asthma
Spirometry findings in asthma
Can be normal
Could show obstruction (FER < 0.70 or < LLN)
Assess reversibility –> significant finding when > 12% and > 200mL increase in FEV1
Role of bronchoprovocation in asthma
Used if strong clinical suspicion and normal spirometry
Direct challenge test with methacholine (>20% fall in FEV1) - good negative predictive valve for excluding active asthma
- false positive seen in allergic rhinitis, CF, heart failure, COPD, bronchitis
Indirect challenge with mannitol or hypertonic saline (>15% fall in FEV1)
- better PPV for asthma than methacholine
Categories in asthma
Intermittent asthma
- Normal FEV1, symptoms/SABA <2/week, no limitations
Persistent asthma
- Mild – normal FEV1, symptoms/SABA >2/week, minor limitation
- Moderate – mildly abnormal FEV1 (60-80%), daily symptoms, some limitations
- Severe – abnormal FEV1 < 60%, daily symptoms + nocturnal, limited function
Notes
- Two or more flares requiring OCS in 12M –> persistent
- Hospital admission or ED presentation –> moderate
- ICU admission –> severe
Formoterol preparations
- Symbicort (budesonide/formoterol)
- Fostair (beclomethasone/formoterol)
- Flutiform (fluticasone/formoterol)
Biologic therapies in asthma
Omalizumab - IgE
Mepolizumab - IL-5
Benralizumab - anti-IL5 receptor
Bupilimub - IL-4 and IL-13
Tezepelumab - TSLP
Typical HRCT features of UIP
Honeycombing
Traction bronchiectasis (least specific)
Reticular opacities (peripheral and lower lobe predominant)
No atypical features
Smoking related ILD
Idiopathic ILD
Respiratory bronchiolitis ILD
Desquamative interstitial pneumonia
Other disease labels of ILD
ILD of known cause
- Dust (asbestosis, silicosis)
- CTD associated
- Hypersensitivity pneumonitis
- Radiation induced
- Drug induced
Granulomatous ILD
- Sarcoidosis
Idiopathic ILD
- Chronic/fibrosing – idiopathic pulmonary fibrosis, idiopathic non-specific interstitial pneumonia
- Acute/subacute – cryptogenic organising pneumonia, acute interstitial pneumonia
- Smoking related – respiratory bronchiolitis ILD, desquamative interstitial pneumonia
Other
- Lymphangioleiomyomatosis (LAM)
- Pulmonary Langerhans histocytosis
Diagnosis of ILD
Clinical data (history and examination)
HRCT
PFTs – helpful to evaluate severity and monitor progress
Pathology (features of autoimmunity)
BAL/biopsy – not always required and not always possible
- If probable UIP pattern on HRCT can be diagnosed as IPF by MDM without biopsy
- Surgical lung biopsy (elective)
* ~1-2% mortality
* Consider if age < 50 yrs, atypical HRCT findings, rapidly progressive disease
- No role in transbronchial biopsy
Indications for lung transplant
Risk of death > 50% within 2 years
Likelihood of surviving > 90 days post TP > 80%
No life-limiting comorbidity (in 5 yrs post TP)
Satisfactory supports/psychosocial
Contraindications of lung transplant
Age > 65 yrs
Smoking/EtOH/drug dependence
Malignancy (5 yrs disease)
Chronic infection
Obesity or malnutrition
Osteoporosis in severe symptoms
Indications for lung transplant in idiopathic pulmonary fibrosis
DLCO < 40% predicted
FVC < 80% predicted
Dyspnoea or functional limitation attributable to lung disease
Decrease in SpO2 to 88%
Role of prednisone/AZA/NAC in ILD
PANTHER study
- Found to be harmful with increased death and hospitalisation
- no physiological or clinical benefit
Role of antifibrotic therapy for ILD
Nintedanib and pirfinedone have been shown to alter disease progression
- suitable for mild/moderate IPF
Nintedanib mechanism of action and side effects
Inhibits multiple tyrosine kinases
Side effects
- Diarrhoea (>60%)
- Nausea (up to 25%)
- LFT derangement
Pirfenidone mechanism of action and side effects
Inhibits TGF-beta and fibroblast proliferation
Side effects
- Rash (30%)
- Nausea (up to 35%)
- Diarrhoea (25%)
HRCT features of non-specific interstitial pneumonia
- Ground glass opacity (partial filling of air spaces but preserved bronchial and vascular markings)
- Reticular opacity
- Traction bronchiectasis
- Diffuse – can have subpleural sparing
- Fibrotic vs cellular
Management of NSIP
- Glucocorticoids
- Second agents – mycophenolate or azathioprine
- Those with more severe disease
- Failure to respond
- Worsens as steroids reduced
- Third line agents – IV cyclophosphamide (monthly), rituximab
- Lung transplantation
HRCT features of hypersensitivity pneumonitis
- Typical features
- Centrilobular nodules and/or ground glass opacities
- Mosaic attenuation (inspiratory), three density pattern, gas trapping (expiratory)
- Fibrosis – linear opacities, coarse reticulation and lung distortion, traction bronchiectasis, honey combing (relative sparing of lower zones, random involvement both axially and craniocaudally)
- Some HP have radiological pattern consistent with UIP reinforces diagnosis of idiopathic pulmonary fibrosis generally only reached if no features suggestive of alternative diagnosis
Clinical features of hypersensitivity pneumonitis
- Recurrent ‘atypical’ pneumonia
- Symptoms after moving to new job or home
- Exposure to pets
- Exposure to moulds
- Hot tub/sauna/swimming pool exposure
- Improvement when on holiday or over weekends
Bronchoscopy and lung biopsy features of hypersensitivity pneumonitis
- BAL – lymphocytic pattern suggestive (~30% lymphocytes)
- TBBx can demonstrate non-caseating granulomas
- Surgical lung biopsy or cryobiopsy where imaging, exposure or BAL are inconclusive
HRCT features of sarcoidosis
- Bilateral hilar and mediastinal LAD
- Nodular (upper zone) + hilar and mediastinal LAD
- Parenchymal – at least stage II disease
Features of Lofgren syndrome
Fever, polyarthritis, erythema nodosum, bilateral hilar lymphadenopathy
Bronchoscopy features of sarcoidosis
- BAL – elevated CD4:CD8 – supportive finding
- Endobronchial biopsy – positive in 40-70%
- Transbronchial biopsy – positive in 50-75%
- EBUS – positive in 80-90%
- Combined approach may have highest yield (>90%)
Extrapulmonary complications and features of sarcoidosis
- Ocular – ophthalmology review
- Calcium – urinary calcium excretion rate, serum Ca2+, vitamin D (1,25)
- Cardiac – ECG, TTE, MRI or PET
- Brain – MRI, LP
Indications and treatment for sarcoidosis
- Indications
- Progressive symptomatic pulmonary disease
- Asymptomatic pulmonary disease with persistent infiltrates or progressive loss of lung function
- Cardiac disease
- Neurological disease
- Eye disease not responding to topical therapy
- Symptomatic hypercalcaemia
- Other symptomatic/progressive extrapulmonary disease
- Treatment
- Inhaled corticosteroids +/- steroid sparing agents
Clinical classification of pulmonary hypertension
Group 1: pulmonary arterial hypertension
Group 2: PH associated with LHD
Group 3: PH associated with lung disease and/or hypoxia
Group 4: PH associated with obstruction
Group 5: PH associated with unclear and/or multifactorial mechanisms