COPD Flashcards
What is COPD
Progressive airway obstruction (FEV1<80%, FEV1/FVC<0.7) with little/no reversibility
Includes chronic bronchitis + emphysema
What is chronic bronchitis
Clinically diagnosed cough, sputum production on most days for 3 mths of 2 successive years
What is emphysema
Histologically enlarged air spaces distal to terminal bronchioles, with alveolar wall destruction
Often visualised on CT
COPD patient types
Pink puffers - inc alveolar ventilation, breathless but not cyanosed with normal PaO2 and low PaCO2
Blue bloaters - cyanosed, dec alveolar ventilation, high PaCO2 and low PaO2 so hypoxic resp drive
COPD signs + symptoms
Cough sputum
Dyspnoea, wheeze
Decreased chest expansion
Cricosternal distance <3cm
COPD complications
Acute exarcebations + infections Cor pulmonale (oedema + raised JVP)
Resp failure
Pneumothorax
Lung carcinoma
COPD tests
FBC shows inc PCV
CXR shows hyperinflation, flat hemidiaphragms, large central pulmonary arteries, bullae
CT shows air space enlargement and bronchial wall thickening
Spirometry - inc RV, TLC and obstructive pattern
General treatments COPD
Smoking cessation
Encourage exercise
Pulmonary rehab offered early when ADLs affected
Mucolytics
Diuretics for oedema
Flu + pneumococcal vaccines
Use of LTOT
Long-term O2 therapy (PaO2 maintained >8 for 15/24h), used for:
Clinically stable non-smokers with PaO2<7.3 despite max treatment
PaO2 7.3-8 and pulmonary HT/ polycythaemia/ peripheral oedema/ nocturnal hypoxia
O2 for terminally ill pts
COPD severity assessment
All have FEV1/FVC <0.7
Mild - FEV1 >80% with symptoms
Moderate - FEV1 50-79%
Severe - FEV1 30-49%
Very Severe - FEV1 <30%
COPD management
SABA/SAMA PRN
If steroid responsiveness then LABA + inhaled corticosteroid
If no steroid responsiveness then LABA + LAMA
LAMA/ICS added if still symptomatic
Azithromycin 250mg 3x per week added if not smoking and >4 exarcebations per year
COPD specialist referral indications
Uncertain diagnosis/ suspected severe/ rapid FEV1 decline
Symptoms disproportionate to lung function tests
Cor pulmonale
Bullous lung disease
Frequent infections (to exclude bronchiectasis)
<10 pack years/ <40yrs
COPD emergency management principles
Ensure oxygenation, treat reversible cause
Start with 24-28% if CO2 retention evidence (blue bloaters), if no evidence then still 28-40% O2 but monitor ABG
ABG within 1h once started O2, aim for PaO2>8 with PaCO2 rise < 1.5
COPD emergency management protocol
Salbutamol 5mg/4h + ipratropium 500µg/6h
O2 therapy, aim for sats 88-92%
IV hydrocortisone 200mg + pred 30mg/d PO for 7-14d
Abx if infection evidence
Physio for sputum expectoration
IV aminophylline if no response to Rx
NIPPV or doxapram 1.5-4mg/min IV (to boost resp if NIV unavailable) if still no response
Intubate + ventilate if pH <7.26 + PaCO2 rising
COPD diagnosis criteria
FEV1/FVC post-bronchodilator <70% in addition to:
symptoms of COPD
or
FEV1<80%