Chronic obstructive pulmonary disease Flashcards
Definition
Chronic
Progressive
Irreversible
Airway obstruction
Chronic bronchitis
Emphysema
Diagnosis of chronic bronchitis
Clinical
3 months. most days, two consecutive years of sputum production and cough
Diagnosis of emphysema
Histological diagnosis
Enlarged airway spaces distal to terminal bronchioles with destruction of alveolar walls
Epidemiology
> 65
10-20% of all >40
Pathophysiology
Chronic inflammation
narrowing and remodelling of airways, increased number of goblet cells, enlargement of mucus-secreting glands of the central airways, and, finally, subsequent vascular bed changes leading to pulmonary hypertension
Decreased elastic recoil, fibrotic changes in lung parenchyma, and luminal obstruction of airways by secretions all contribute to increased airways resistance. Expiratory flow limitation promotes hyperinflation
Comparing pink puffers and blue bloaters
Pink puffers->+alveolar ventilation, normal 02, normal/low CO2. Breathless, not cyanosed. May progress to type 1 respiratory failure
Blue bloaters->-ve ventilation, hypoxemic and hypercapnic. Not breathless, cyanosed. May progress to cor pulmonale
Main symptoms
Breathless
Cough
Sputum
Wheeze
Signs
Tachypnoeic Cyanosed Use of accessory muscles Pursed lipped breathing Tracheal tug Plethoric
Reduced chest wall expansion
Hyper-resonant
-ve air entry
Quiet breath sounds
Evidence of cor-pulmonale->distended neck veins, hepatojugular reflux, loud P2, edema
Complications
Acute exacerbation Typer 1 respiratory failure Cor pulmonale Pneumothorax Polycythemia Lung cancer
Investigations and findings
Spirometry->FEV1/FVC ratio PaCO2 >50 mmHg and/or PaO2 of Flattened diaphragm, hyperinflation, large central pulmonary arteries, -ve vascular markings, bullae
FBC->+HCT, possible +WCC
ECG->RA and RV hypertrophy
Pulmonary function tests
Severity of COPD->mild, moderate, severe
Mild: FEV1 50-80% predicted
Moderate: FEV1 30-49% predicted
Severe: FEV1
Consultation checklist
SMOKES Smoking cessation Medications Oxygen Komorbidities->cardiac, sleep apnea, osteoporosis, depression, asthma
Pharmacotherapy options
short-acting β2-agonists (salbutamol, terbutaline) short acting anticholinergic drugs (ipratropium bromide) long-acting β2-agonists (eformoterol, salmeterol); long-acting anticholinergic drugs (tiotropium); and corticosteroids.
Management of mild
SABA before exercise->Salbutamol 200mcg as needed
1-2 puffs/4-6 hours
Patient education->disease progress, symptoms of exacerbation
Influenza/Pneumococcal
Smoking cessation
Advice: Avoid pollution Cool dry areas Avoid cold/flu Optimise diet and lifestyle
Management of moderate
Regular combined LABA (salmeterol) + anticholinergic (tiotropium), +SA dilator Salbutamol 200mcg as needed 1-2 puffs/4-6 hours Terbutaline 500mcg as needed Ipratropium 42 mcg Atrovent 1-2 puffs 4 X daily
Advice: Avoid pollution Cool dry areas Avoid cold/flu Optimise diet and lifestyle Education Smoking cessation Pulmonary rehab