COPD Flashcards
What is the disease process of COPD?
Cigarette smoke —> alveolar macrophage — (neutrophil chemotatic factors, cytokines (IL-8), mediators (LTB4), oxygen radicals > neutrophil —> proteases —> aveolar wall destruction (emphysema) + mucus hypersecretion (chronic bronchitis) —> progressive airflow limitation
What are the disease components of COPD?
Chronic Bronchitis:
- chronic neutrophilic inflammation (10% patients also have eosinophilic inflammation)
- mucus hypersecretion
- mucociliary dysfunction
- altered lung microbiome
- smooth muscle spasm and hypertrophy
- partially reversible
Emphysema:
- alveolar destruction
- impaired gas exchange
- loss of bronchial support
- irreversible
How to tell if someone has emphysema?
-Reduced breath sounds
-Reduced DLCO (diffusing capacity of Carbon Monoxide)
-Black holes on CXR or HRCT (high-resolution computed tomography)
What is the assessment for COPD?
Asses symptoms
Assess degree of airflow limitation using spirometry
Assess risk of exacerbations
Assess co-morbidities (e.g. IHD/HF)
two exacerbation or more within the past year or FEV1 < 50% predicted are indicators of high risk
How to grade COPD? (GOLD and groups ABE)
GRADE FEV1 (% PREDICTED)
GOLD 1 >(or equal to) 80
GOLD 2 50-79
GOLD 3 30-49
GOLD 4 <30
Group A
= 0 or 1 moderate exacerbations (not leading to a hospital admission) + mMRC 0-1, CAT <10
Group B
= 0 or 1 moderate exacerbations (not leading to a hospital admission) + mMRC > (or equal to) 2, CAT >(or equal to 10)
Group E
= > (or equal to) 2 moderate exacerbations or > (or equal to) 1 leading to hospitalisation (doesn’t matter the mMRC or CAT
What is the clinical presentation of COPD?
Chronic symptoms - not episodic
Smoking
Non-atopic
Daily productive cough
Progressive breathlessness
Frequent infective exacerbations viral/bacterial
Chronic bronchitis-mucous hypersecretion
Emphysema - reduced breath sounds
What is the chronic cascade in COPD - real medicy
Progressive fixed airflow obstruction (both FEV1 & FVC reduced ratio <0.70)
Impaired alveolar gas exchange
Respiratory failure: decreased PaO2 and increase PaCO2
Pulmonary hypertension
Right ventricular hypertrophy/failure (i.e cor pulmonale)
Death
Stopping smoking arrests further decline in lung volume
What is asthma COPD overlap syndrome (ACO)
COPD with blood eosinophilia >30/ul
Responds better to ICS wrt exacerbation reductions
More reversible to salbutamol
Difficult to distinguish ACO from Type 2 asthmatic smokers who have airway remodelling (ie reduced FVC)
Asthma VS COPD
ASTHMA
Non smokers
Early or lat onset
Intermittent symptoms
Non-productive cough
Non-progressive
Eosinophilic inflammation
Diurnal variability
Good corticosteroid response
Good bronchodilator response
Preserved FVC and DLCO
Normal gas exchange
COPD
Smokers
Non allergic
Late onset
Chronic symptoms
Productive cough
Progressive decline
Neutrophilic inflammation*
No diurnal variability
Poor corticosteroid response*
Poor bronchodilator response
Reduced FVC and DLCO
Impaired gas exchange
*except in ACO with Eos COPD
management of COPD
Non-pharmacological
- smoking cessation +/- nicotine/bupropion/varenicline
- Immunisation: influenza/pneumococcal
- physical activity
- oxygen - domiciliary
Venesection
Lung vol reduction
Stenting
Pharmacological
- LABA/LAMA combo
- ICS/LABA/LAMA combo
PDE4I-Roflumilast
Mucolytic - Acetylcysteine
Antibiotics - Azithromycin
What are the aims of the treatment and the treatment of COPD?
Aims- reduce exacerbations, improve pulmonary function, improve QOL, prevent pulmonary heart disease
- Treatments include:
- Smoking cessation
- Immunisation
- Pharmacotherapy
- Pulmonary rehab
- Oxygen
What is the initial pharmacological treatment in COPD patients according to their group (ABE)
Group A: bronchodilator
Group B: LABA+LAMA*
Group E: LABA+LAMA* (consider LABA+LAMA+ICS if blood eos >(or equal to) 300
*Single inhaler therapy may be more convenient and effective than multiple inhalers
Summary of ICS in COPD
Non-eosinophilic and infrequent exacerbation = no ICS
ICS/LABA/LAMA > LABA/LAMA (ICS/LABA not used)
- in eosinophilic frequent exacerbator
All ICS have increased risk of pneumonia
- those which are lipophilic have greatest risk (FF/PP)
What is the treatment for acute COPD?
- Nebulised high dose salbutamol + ipratropium
- Oral prednisolone
- Antibiotic (amoxicillin/doxycycline) if infection
- O2 titration against Pa)2/PaCO2
- Physio to aid sputum expectoration
- Non-invasive ventilation to allow higher FiO2 (fraction of insured oxygen - conc. of O2 in the gas mixture)
- Intensive therapy unit (ITU) intubated assisted ventilation to buy time if reversible component (e.g. pneumonia)
Mucolytics
- Oral acetylcytesine, carbocisteine
- to reduce sputum viscosity and aide sputum expectoration (and reduce exacerbations) in COPD/bronchiectasis
- rarely used - only as add on to other treatments
