10: COPD Flashcards
1
Q
COPD definition
A
Chronic airflow obstruction due to chronic bronchitis and/or pulmonary emphysema.
Not acute (bronchitis/bronchiolitis, asthma attack).
Not completely reversible (asthma).
Obstruction: FEV1/FVC < 70% or lower limit of normal.
Chronic bronchitis: persistent cough and sputum production of at least 3 months in at least 2 consecutive years.
Pulmonary emphysema: destruction of acinar walls leading to loss of radial traction of airways and increased lung compliance.
2
Q
COPD risk factors
A
- Cigarette smoke
- Occupational dust and chemicals
- Environmental tobacco smoke (ETS)
- Indoor and outdoor air pollution
- Genetic variation
3
Q
alpha-1-antitrypsin (AAT) deficiency
A
- Autosomal co-dominant disorder caused by mutation in SERPINA1 gene
- M = normal allele
- S, Z = mutated –> intracellular degradation or accumulation
- SZ = 20-50% risk of emphysema
- ZZ = 80-100% risk of emphysema
- AAT inhibits neutrophil elastase
- Panlobular emphysema
- Younger pts w/ basilar emphysema
- Can also cause liver dz
- Tx: pooled plasma alpha-1-antitrypsin (slow decline of lung function)
4
Q
COPD pathophysiology
A
- Increased RV, TLC 2/2 increased lung compliance –> hyperinflation
- Hypoxemia 2/2 low V/Q (poor ventilation), alveolar hypoventilation (no shunt/diffusion abnormalities)
- ↑dead space ventilation (emphysematous regions poorly perfused, ↑WOB)
5
Q
COPD presentation
A
- Early: asymptomatic
- If symptomatic:
- Cough w/ sputum (chronic bronchitis)
- Exertional dyspnea
- Muscular wasting
- ↑AP chest diameter
- Bilaterally diminished breath sounds
- During exacerbation:
- Change in sputum quantity, color, consistency
- Wheezing, rhonchi
- Increased dyspnea
- Cyanosis
6
Q
COPD diagnosis
A
- Clinical presentation
- Airflow obstruction on spirometry (no/little reversibility w/ bronchodilator)
- Exclusion of alternative causes
7
Q
COPD staging
A
- **Stage I **(mild): FEV1 > or = 80%; any ABG
- **Stage II **(moderate): FEV1 50-79%, any ABG
- Stage III (severe): FEV1 30-49%, PaO2 > 60, PaCO2 < 50
- Stage IV (very severe): FEV1 30-49%, PaO2 < 60, PaCO2 50
8
Q
Management by COPD stage
A
- Stage 1: risk factor reduction, influenza/pneumococcal vaccination, SABA
- Stage 2: long-acting inhaled bronchodilators, pulmonary rehab
- Stage 3: inhaled corticosteroids
- Stage 4: long-term O2, surgical therapy
9
Q
Nicotine replacement
A
- **Polacrilex **(gum)
- Lozenges
- Spray
- Inhaler
- Patch
25% 6-month abstinence rate
10
Q
Buproprion
A
- PO therapy for tobacco cessation
- 24% 6-month abstinence rate
11
Q
Varenicline
A
- PO partial agonist of nicotinic ACh receptor for tobacco cessation
- Stimulates receptor (reduce withdrawal)
- Block nicotine binding (reduce reward)
- 33% 6-month abstinence rate
- SFx: nausea, HA, insomnia, abnormal dreams, depression/suicide, ↑risk CV events
12
Q
Albuterol
A
- SABA
- Sx relief
13
Q
Terbutaline
A
- SABA
- Sx relief
14
Q
Salmeterol
A
- LABA
- Controller
15
Q
Ipratropium
A
- Short-acting anti-cholinergic
- Sx relief (slower than SABA)
