COPD: Diagnosis And Treatment Flashcards
What is COPD?
Chronic Obstructive Pulmonary Disease: Characterised by: - Progressive airflow obstruction - Neutrophilic inflammation - Irreversible disease - No cure - Predominantly caused by smoking
How do you calculate pack years?
(No. smoked per day X No. years smoked)/20
What causes/risk factors associated with COPD?
Smoking.
- Age (> 35 years)
- Gender
- Occupation (builders etc.)
- Genetic factors (deficiency of alpha-1 adrenoceptors/trypsin enzyme)
- Air pollution
- Socio-economic status (poorer more likely to smoke)
What is the pathophysiology (observed change to physiology) of COPD?
Chronic Bronchitis:
- Inflammation of airways; w/e narrowing + mucus hypersecretion
Emphysema
- Destruction of alveoli (membranes break down and lose elasticitiy), airways collapse, hyperinflation of lungs (interfering with expulsion of air); ‘dead’ air gets trapped in lungs thus shallow breathing
What may result from gas exchange abnormalities?
Hypoxia (deficiency of oxygen) Respiratory acidosis (hence increased levels of CO2 in blood which decreases blood pH)
How is COPD diagnosed?
No single test:
Clinical judgement:
- Patient history (>35 years/smoking)
- Physical examination (signs and symptoms)
- Spirometry
- X-ray (rule out lung cancer)
What are the symptoms of COPD?
- Chronic cough (usually 1st symptom; often ignored as patient thinks it’s smoker’s cough)
- Breathlessness when exerting themselves (even when at rest)
- Regular sputum production (observed in half of smokers; change in colour to yellow/green means infection)
- Frequent winter chest infection
- Wheeze
What other diseases share COPD’s symptoms and how would you rule them out?
- Rapid weight loss/waking up at night/pyrexia (TB)
- High BMI (obesity)
- Fatigue/chest pain/raised blood pressure (CVD)
- Pyrexia (infection)
What are the signs of COPD?
- > 35 years of age/onset of symptoms in later life
- Hyperinflated chest (trapped air)
- Wheeze/quiet breath sounds
- Pursed-lip breathing
- Peripheral oedema
- Cyanosis (blue tinge to skin due to lack of O2)
- Clubbing of nails (swollen)
- Nicotine staining of fingers and nails
- Underweight
- Use of accessory muscles (clinging onto edges with hands etc.)
What are the two characteristic groups of COPD?
Pink Puffers: emphysema
Blue Bloaters: bronchitis
How is COPD considered a systemic disease rather than a respiratory?
- Pulmonary hypertension
- Muscles weakeness
- Osteoporosis (from steroid treatment)
- Depression (mental health)
How is spirometry important with regards to COPD diagnosis?
Spirometry measures patient lung function.
- If the FEV1/FVC ratio is
What is FEV1?
Forced expiratory volume in one second
What is FVC?
Forced vital capacity - the maximum volume of air that ca be exhaled from the lung
When is spirometry testing performed with COPD?
- At the time of diagnosis
- To reconsider diagnosis after response to treatment
What are the aims of COPD treatment?
COPD is incurable; only smoking cessation reduces FEV1 decline, drugs treat the symptoms.
- Prevent and control symptoms (drug therapy)
- Reduce frequency and severity of exacerbations
- Improve quality of life
- Improve exercise tolerance
- Prevent disease progression
- Minimise side effects
What is the NICE guideline for COPD treatment for an FEV1 > 50%?
1.) SABA or SAMA as required
2.) LABA or LAMA (discontinue SAMA)
[after LABA > LABA + ICS (inhaled corticosteroid)]
3.) LAMA + LABA + ICS (triple therapy)
4.) Theophiline
What’s the difference in dose frequency between a LABA and a LAMA and what devices are they?
LABA: Salmeterol pMDI (BD)
LAMA: Tiotropium dry powder (OD) - more convenient(?)
What is the difference in NICE guideline COPD treatment for an FEV1 50%?
Go straight to LABA + ICS instead of just LABA.
What should be considered before stepping up therapy?
- Patient’s inhaler technique (correct usage?)
- Adherence to therapy (actually using the inhaler?)
- Smoking status (cessation pls)
- Attendance at pulmonary rehabilitation (exercises that improve breathing)
- Signs of anxiety or depression
Name a commonly used SABA.
Salbutamol/terbutaline
Name a commonly used SAMA.
Ipratropium
Name a commonly used LABA
Salmeterol/formoterol/indacaterol
Name a commonly used LAMA
Tiotropium/aclidinium/glycopyrronium
How do ICS’ (inhaled corticosteroids) work and when are they used?
- Reduce eosinophilic inflammation (only arises w/exacerbations as COPD is primarily neutrophilic inflammation)
- Of benefit if FEV1
What are the side effects associated with ICS use?
- Pneumonia
- Adrenal suppression (adrenal gland normally makes the body steroids)
- Diabetes
- Osteoporosis (brittle bones prone to fracture rising from steroid usage)
When would oral bronchodilators be used and how do they work?
What are the pharmacokinetic issues?
- Theophylline, last line treatment after ‘triple therapy’ used when all other steps exhausted.
- Anti-neutrophilic inflammation activity
- HOWEVER v.narrow therapeutic window (requires loading dose first to get it up to it) thus plasma levels need to be monitored
- Smokers possess more of the enzyme to metabolise it; give higher dose
- Elderly are more sensitive to it; give lower dose
When is long-term oxygen therapy (LTOT) considered and what conditions are required for efficacy?
- When PaO2 (partial pressure in arteriole blood)
What other therapies exist for COPD?
Vaccinations
- Pneumococcal
- Influenza
Pulmonary rehabilitation
- Structured exercise therapy (improves aerobic function)
Mucolytics (aid clearance of mucus)
- e.g. Carbocisteine (reduces frequency of exacerbations and used as add-on to bronchodilators)
What is an exacerbation of COPD the symptoms of?
- Increase in eosinophil numbers (normally neutrophilic inflammation)
- Worsening breathlessness
- Cough
- Increased sputum production
- CHange in sputum colour (to green/yellow)
- Worsening peripheral oedema
“Sustained worsening of patient’s symptoms from usual state that is beyond normal day-to-day variations and is acute in onset”
How are exacerbations managed?
- Increase bronchodilator frequency/usage
- Oral corticosteroids; prednisolone 30mg/day for 7 to 14 days
- Antibiotics: aminopenicillin/macrolide/tetracycline
- Oxygen
(Rescue packs exist where patient has short-term steroids/antibiotics they can start on before seeing GP)
