COPD Flashcards
What is COPD?
Chronic Obstructive Pulmonary Disease. Number of lung conditions that cause incomplete reversible poor outflow and inability to breathe out air fully. It includes Emphysema and Chronic Bronchitis. Emphysema is damage to the alveoli in the lungs and Chronic bronchitis is long standing inflammation of the lungs.
What is the pathophysiology of emphysema?
Destruction of the alveoli walls with no obvious fibrosis. The Alveoli lose elastic recoil so they distend and air becomes trapped in the alveoli. Loss of alveolar SA leads to impairment in gas exchange. Loss of elastic tissues causes the lung to hyperinflate
What are bullae?
Larger redundant airspaces within the lungs due to progression of emphysema
What are the signs of COPD?
Use of accessory muscles Hyperinflation Pursed lip Tachypnoea Cachexia Flapping tremor Quiet breathing sounds
What are some symptoms of COPD?
Short of breath
Chronic cough
Sputum production
Wheeze
What can be seem on spirometry with COPD?
Shows obstructive airflow
FEV1/FVC is less than 70%
Spirometry alone cannot separate asthma from COPD
What are some differential diagnoses for COPD?
Asthma
Bronchiestasis
Congestive Heart failure
Lung cancer
What other investigations can be done to diagnose COPD?
CXR - exclude other pathologies
FBC - exclude anaemia or polycynthaemia
What are the risk factors for COPD?
Smoking Alpha 1 antitrpysin deficiency Age Family History Air pollution
What are some of the complications of COPD?
Cor pulmonale - pulmonary hypertension cuases right ventricular hypertrophy and then progresses to cor pulmonale
Respiratory Failure
Pneumothorax
Infection
How is COPD treated?
Smoking cessation
Bronchodilators –> salbutamol
inhaled corticosteroids (controversial)
Short acting muscarinic antagonist –> ipatropium bromide
Long acting muscarinic antagonist –> tiotropium
Methylxanthines - theophylline
Mucolytic therapy for those with a chronic productive cough
Pulmonary Rehab
Why should a COPD patient not be given high flow oxygen?
because this will knock of their hypoxic drive as the central chemoreceptors have reset to a higher PaCO2 as CSF acidity has been corrected by the choroid plexus cells and respiration in COPD patients is driven by hypoxia.
Also reduces hypoxic vasoconstriction in poorly ventilated areas and this worsen v/q mismatch because arterioles dilate but CO2 removal is still an issue
what should be the goal oxygen saturation in a COPD patient?
88-92%
What would an ABG show in an acute exacerbation of COPD?
Respiratory acidosis and type 2 resp failure
What would be seen on a CXR in a patient with COPD?
Flattened hemi-diaphragms Hyperinflation (more than 8 anterior ribs seen) Bullae present Prominent Hila Decreased lung markings
