COPD Flashcards
How does bronchitis occur?
Increase in mucus secreting goblets cells in the bronchi. These show infiltration of CD8+ which is then followed by formation of scar tissue and thickening of bronchi walls leading to narrowed airways. As this progresses it can lead to metaplasia and fibrosis of the bronchial walls
What are the different types of COPD?
Chronic bronchitis
Emphysema
Small airway inflammation (resp bronchiolitis)
Define emphysema
An increased air space distal to the terminal bronchioles
What happens in emphysema?
There is a loss in elastic recoil of the lung with collapse of small airways during expiration obstruction the outflow of air.
What causes the V/Q mismatch in COPD?
Not all air is expired so some deoxygenated air remains in lung. Inspiration then fills lungs to normal ventilation but perfusion is low as concentration of O2 is less
How is CO2 retention caused in COPD?
Inability to fully expire leading to CO2 not being blown off and building up in the lungs and tissues
Why is it bad to give COPD patients oxygen?
If they retain CO2 and become hypoxic they may become desensitised to CO2 and regulate their respiration due to their hypoxaemia rather than the high CO2 concentration like normal. Therefore, giving oxygen restores their O2 sats causing their respiration to become uncontrolled
What causes the blue bloater effect in COPD?
Control of respiration by hypoxaemia causes renal hypoxia which causes fluid retention leading to oedema and cyanosis in the patient
What causes COPD and how?
Smoking. It increases neutrophils granulocytes which release elastases which destroy alveolar wall connective tissue. Smoking also inhibits alpha 1 antitrypsin which usually inhibits elastase further leading to destruction of alveolar walls
Symptoms of COPD?
Wheeze Cough > 3 months Breathlessness Frequency chest infection Worsened by cold
Signs of COPD?
Expiratory Wheeze Tachypnoeic Use of accessory muscle Pursing of lips on expiration Breathless Cyanosis CO2 flap
Investigations for COPD?
Liver function tests
CXR
CT scan
Treatment of COPD?
Smoking cessation SABA LABA LABA + LAMA LABA + corticosteroid Diuretic is have oedema
Complications of long standing COPD?
Cor pulmonale:
Fluid retention due to hypoxia of the kidneys leads to pulmonary hypertension and RVH.
Example of SABA for COPD?
Salbutamol
