COPD Flashcards
What is airflow obstruction
Measured by spirometry.
Ratio of forced expiratory volume in one sec to forced vital capacity (FEV1/FVC) <0.7 = air flow obstruction
What is chronic bronchitis
Clinical term referring to cough and sputum production for atleast 3 months in each of consecutive 2 years
What is emphysema
Pathological term referring to loss of parenchymal lung texture ( destruction of alveoli ).
What is emphysema
Pathological term referring to loss of parenchymal lung texture ( destruction of alveoli ).
COPD risk factors
Smoking Genes Age/gender Lung growth / development Exposure to particles - cigarette smoke , occupational dust and fumes , indoor air pollution Socioeconomic status Asthma / bronchial hyperactivity Chronic bronchitis
Pathological changes with COPD
Lung parenchyma Chronic inflammation ( increase in inflammatory cells) Structural changes (repeated injury and repair 0)
Resulting in
Increase resistance to airflow obstruction in small conducting airways
Air trapping
Progressive airflow obstruction
Pathogenesis of COPD
Oxidative stress
Imbalance of proteases and anti proteases
Physiological abnormalities
Mucous hypersecretion - chronic productive cough
Ciliary dis function - struggling to cough up phlegm
Air flow obstruction and hyper inflation - breathlessness and limited exercise capacity
Gas exchange abnormalities - hypoxaemia (low) and hypercapnia ( high)
Pulmonary hypertension due to vasoconstriction of vessels leading to deoxygenated areas
Systemic affects - skeletal muscle wasting , increased risk of CVD, anxiety and depression
Diagnosis
Suspect COPD in people aged >35 yrs with a risk factor >= 1 of following symptoms Breathless Chronic / reoccurring cough Regular sputum production Frequent lower resp tract infections Wheeze
Other symptoms Weight loss Ankle swelling fatigue Blueish coat to skin Hyper inflated chest
What does a spirometer measure
Volume of air patient is able to expel from lungs after maximal inspiration
Classification of mild COPD
FEV1>= 80% predicted
Classification of moderate COPD
50% <= FEV1 < 80% predicted
Classification of severe COPD
30%<= FEV1< 50% predicted
Classification of very severe COPD
FEV1 < 30% predicted
Goals of COPD therapy
Relieve symptoms
Prevent disease progression
Improve exercise tolerance and health status
Prevent and treat exacerbations and any complications
Reduce mortality
Non pharmaceutical management of COPD
Smoking cessation
Vaccinations
Pulmonary rehabilitation
Short acting B2 agonist. Example and duration of action
Salbutamol. 4-6 hrs. Inhaler technique.
Long action beta 2 agonist. Example and duration of action
Salmeterol. 12+ hrs. Inhaler technique
Short acting muscarinic antagonists - example
Ipratropium bromide- slower onset of action than SABA . Inhaler technique
LABA - examples
Tiotropium. Longer duration of action than LABAs . Inhaler technique.
Types of drugs used to treat COPD
LAMA SAMA LABA SABA Methyxanthines Inhaled corticosteroids (ICS) Oral corticosteroids Phosohodiesterase type-4 inhibitors
Methylxanthines
For those unable to take inhaled drugs or symptoms get worse
Eg theophylline
Releasable airway smooth muscle
Dose related to toxicity. Narrkw therapeutic window. Significant interactions
ICS
Eg beclomethasone
Increased risk of pneumonia
Withdraw may lead to exacerbations
Mono therapy not recommended
Good inhaler technique needed for oral thrush prevention
Oral steroids
Eg prednisolone.
Advanced disease only . Low dose. Numerous side effects
Phosphodiesterase type 4 inhibitors
Eg roflumilast
Add on therapy to bronchodilators for those w severe COPD
duration of action is 24 hrs
More adverse effects than inhaled medication
Delivery systems used to treat patients with stable COPD
Inhalers
Spacer devices
Nebulisers
When should spacers be used
All those on high ICS
most elderly using standard metered dose inhalers
What is carbocistiene
Mucolytic. Helps you cough up phlegm
Who should be considered for oxygen therapy .
Very severe airflow obstruction (FEV1 <30% predicted )
Cyanosis
02 saturations <= 92% breathing air
What is an exacerbation
A sustained acute onset worsening of the patients symptoms from their usual stable state which goes beyond normal day to day variations .
Commonly reported symptoms of exacerbations
Worsening breathlessness Increase sputum volume and colour (y/g colour) Cough Wheeze RTI
Pharmacological management of exacerbations
Increased dose of SABA
oral corticosteroids may be used if no c/I
Prednisolone 30mg daily for 5 days
Antibiotics if exacerbation is ass with history or more purulent sputum
Oral first line
IV theophylline if adequate response to nebulised bronchodilators
Oxygen sat measured and given if needed
Non invasive ventilation
Asses need for intubation
How often should patient be sen for mild / moderate / severe COPD
At least annual
How often should patient Be seen for very severe COPD
twice a year
