COPD - Definition
Respiratory disorder largely caused by smoking, and is characterized by progressive, partially reversible airway obstruction and lung hyperinflation, systemic manifestations, and increasing frequency and severity of exacerbations.
Cost of COPD to the System
COPD ranges from 1st to 5th most common cause of admission to hospitals.
Mean length of hospital stay for AECOPD was 11 days.
Estimated cost per stay was $10,000.
Screening for COPD
Does not make feasable sense to screen asymptomatic individuals
If a smoker or ex-smoker presents with any of the below, send them for spirometry:
- Coughing regularly
- Coughing up phlegm regularly
- Simple chores making you short of breat
- Wheezing during exertion
- Get frequent colds that last longer
Spirometry is essential.
FEV1/FVC of <0.7
Look at post-bronchodilator FEV1
DDx for COPD
Central airway obstruction (cancer, lymphadenopathy, central airway stenosis)
Diffuse Pan bronchiolitis
Risk Factors for COPD
Smoking (20-50% of smokers will develop significant COPD)
Other risks include occupational exposures
Inflammation in COPD
COPD is a low-grade inflammatory disease of the lungs with systemic manifestations.
In the systemic circulation, there are increased levels of activated inflammatory cells, and increased levels of pro-inflammatory cytokines such as TNF-a, IL-8, and LT-B4.
Compare these two. Normally, there will be a gap between regular breathing and the line of maximum expiration. The area in between indicates there is no flow-limitation.
In patients with COPD, regular breathing is the same rate of expiration as in maximum expiration, and they are flow-limited.
"Scoop" in Flow-Volume Curve
You need to take another breath before you are finished exhaling the previous breath often due to an obstructive airway problem.
Management of COPD
Determine severity using spirometry, symptoms, and history
Diagnose and manage comorbidities
Non-pharmacologic and pharmacologic treatment
Determination of COPD Severity
Mild: FEV1 > 80% predicted, FEV1/FVC <0.7
Moderate: 50% < FEV1 < 80% predicted, FEV1/FVC <0.7
Severe: 30% < FEV1 < 50% predicted, FEV1/FVC <0.7
Very Severe: FEV1 < 30% predicted, FEV1/FVC <0.7
Mild: SOB from COPD when hurrying on the level, or walking up a hill
Moderate: SOB from COPD causing the patient to stop walking after 100m
Severe: SOB from COPD resulting in being too breathless to leave home
Effective inhaler technique
Early recognition and treatment of acute exaberations
Vaccinations and COPD
It is very important for patients with COPD to be up-to-date on their vaccinations.
Getting sick can trigger an acute exaberation of their COPD.
* No role for ICS alone *
Asthma vs COPD
Age of onset - asthma is usually younger, but COPD is usually >40
Smoking - asthma is not causal, but COPD is usually >10 pack years
Sputum production - infrequent in asthma, often in COPD
Allergies - often in asthma, infrequent in COPD
Disease course - stable (with exaberations) in asthma, progressive in COPD
Spirometry - often normalizes in asthma, does not normalize in COPD
Acute Exacerbation of COPD (AECOPD)
Acute worsening of COPD symptoms beyond day-to-day variations. This includes an increase in dyspnea, an increase in cough, a change in sputum production.
Basically a "COPD flare".
50% of patients who are hospitalized from an episode of AECOPD are dead within 4 years.
Management of AECOPD
Increased doses of inhaled SABA and inhaled anticholinergic medication.
Oral or parenteral corticosteroids.
Antibiotics for new increased expectoration of mucopurulent sputum and dyspnea.