Respiratory: COPD Flashcards
What is COPD?
COPD is airflow obstruction that is progressive, not fully reversible and does not change markedly over several months. It is predominantly caused by smoking.
What diseases does COPD encompass?
Emphysema, chronic bronchitis and non reversible asthma
What is emphysema?
Destruction of terminal bronchioles and distal air spaces leading to loss of alveolar SA. Forms bullae which are large redundant airspaces.
Destruction of supporting tissue (elastic tissue)
Why is there hyperinflation of the lungs in emphysema?
There is loss of elastic tissue therefore the lungs are unable to resist the natural tendency of the rib cage to expand outwards resulting in hyperinflation.
What is chronic bronchitis?
Chronic mucus hypersecretion caused by inflammation of the large airways.
Results in a chronic productive cough and frequent respiratory infections
What are the causes of COPD?
- Smoking (major cause)
- alpha 1 antitrypsin deficiency (younger pts)
- pollution
What are the symptoms of COPD?
Productive cough
Progressive breathlessness
How do you assess the severity of breathlessness?
MRC dynspnoae score
What are some of the signs of COPD?
Purse lip breathing - increases the pressure within the airways
Increased RR
Using accessory muscles
Hyperinflation
How is COPD diagnosed?
Need to measure the airway obstruction using spirometry. It is important to quantify the severity of airway obstruction.
How is stable COPD managed?
Multidisciplinary approach:
Smoking cessation (significant improvement no matter how old) , symptomatic relief eg bronchodilators, steroids, mucolytics
Long term oxygen therapy and lung volume reduction considered
What are some surgical options to manage COPD?
Lung volume reduction to get rid of dead space - reduces hyperinflation
Lung transplant considered for younger patients
What is the management of acute exacerbations of COPD?
Request ABG on air due to hypoxia
- aim for sats of 88-92% with titrated O2
- salbutamol nebuliser
- oral steroids
- if infective give antibiotics
Repeat ABG and if no better consider non invasive or invasive ventilation
What is non invasive ventilation and who is it suitable for?
Ventilatory support using a mask - the pt has to breathe in sync with the machine
Useful for COPD with type 2 resp failure and mild acidosis - pts must be conscious to use it
