COPD Flashcards
Which 3 conditions characterise COPD
Emphysema
Chronic bronchitis
Small airway fibrosis
What is chronic bronchitis
Productive cough for at least 3 months in 2 consecutive years
New goblet cells in small airways and increase in number in larger airways —> increased mucus production
What is emphysema
Destroys alveoli, increases residual volume
Smoking typically causes apical emphysema
Risk factors for COPD
Tobacco smoking, air pollution, smaller lungs, female, increasing age
Which deficiency leads to basal and panacinar emphysema
Alpha-1-antitrypsin deficiency
Presents in younger patients
Typical history of COPD
- progressive dyspnoea
- chronic productive cough
- recurrent LRTI
- fatigue
- headache
- (hypercapnia) and flapping tremor (hypercapnia)
What to expect in examination of COPD
tachypnoea wheeze pursed lips breathing barrel chest peripheral cyanosis flapping tremor raised JVP use of accessory muscles for breathing
What condition can arise from chronic hypoxia in COPD
Cor pulmonale (right sided heart failure) —> chronic hypoxia in COPD leads to pulmonary vasoconstriction and
consequent pulmonary hypertension leading to right heart failure,
presents as:
- peripheral oedema and hepatomegaly; chronic hypoxia also leads to secondary polycythaemia
What is target Sats in COPD
88-92%
Types of emphysema (centriacinar, panacinar, periacinar)
Centriacinar - lose tissue in middle acinus
Panacinar - widespread
Periacinar - around edges
What criteria need to be met for long term oxygen therapy in COPD
Oxygen level below 7.3kPa + pulmonary hypertension or polycythaemia (abnormal haemoglobin concentration in blood)
Contraindicated in present smokers
What type of respiratory failure can COPD lead to
Type 2:
Increased CO2 —> those with retained CO2 are said to be on hypoxic drive due to desensitisation of central chemoreceptors —> reliance of peripheral chemoreceptors
