COPD Flashcards
Which two conditions are components of COPD
Chronic bronchitis and emphysema
What brings about an inflammatory response in COPD
Exposure to noxious substances such as cigarette smoke, cannabis, resin, dust exposure.
When does the changes to the lungs of COPD become irreversible
In the early stages, symptoms and pathophysiology is reversible. However, in the long term, irreversible changes occur such as the breakdown of the respiratory tissues with particular damage to small airways and alveoli.
What is produced in excess in COPD
Mucus.
Why are patients with COPD vulnerable to recurrent infection
Due to poor ventilation and a degree of immunocompromise.
What non-pulmonary complications can arise from COPD
- Hypoxia leads to pulmonary vasoconstriction to try and match ventilation and perfusion. This causes pulmonary hypertension which puts back pressure on the heart and can cause right sided heart failure (cor pulmonale) with ankle oedema.
- Peripheral oedema
- Weight loss
- Muscle wasting
- Osteoporosis (partly due to poor nutrition and partly due to long term corticosteroid use).
What is chronic bronchitis
Inflammation in the airways and excess mucus production. This leads to obstruction of air flow.
What is emphysema
The breakdown of small airways and alveoli due to inflammation and proteolytic enzymes from white cells.
What becomes an issue with the lack of tissue in the lung caused by emphysema
There is less elastic recoil in the small airways which then tend to collapse. Air trapping is the result.
What are three risk factors for COPD
- Smoking
- Occupation
- Recurrent infection.
What are the signs of COPD
- Hypoxia
- Cyanosis
- Tachypnoea
- Pursed lip breathing to try and maximise pressure in the airways during the expiratory phase and prevent the small airways from collapsing.
What are the three pillars that make up the management of COPD
- Lifestyle changes
- Pharmacological management
- Occasionally surgical management.
What is the most important lifestyle change that can be made by people with COPD
Smoking cessation.
What four things can be used in pharmacological management of COPD
- Oxygen
- Bronchodilators
- Corticosteroids
- Antibiotics
What are three types of bronchodilators used in COPD management
- Beta 2 agonists
- Theophyllines
- Anti-muscarinic drugs
What is an example of a corticosteroid that can be taken orally and is used to treat acute exacerbations of COPD
Prednisolone.
Why are antibiotics used in people with COPD
Because these people are more prone to recurrent infection which exacerbate the COPD symptoms. COPD patients should be managed with antibiotics at an early stage.
What do beta two agonists do in the lungs
There are beta 2 receptors present in the lungs. These are normally bound to by neurotransmitters such as adrenaline which is part of the sympathetic nervous system, to bring about bronchodilation. This increases the lumen of the bronchi and increases airflow. Beta 2 agonists mimic this action to bring about bronchodilation.
What is the normal action of muscarinic receptors in the lungs
The smooth muscle surrounding the airways is innervated by cholinergic parasympathetic nerves for which acetylcholine is the neurotransmitter. When acetylcholine binds to muscarinic receptors, this brings about bronchoconstriction and mucus secretion.
What do anti-muscarinic drugs do
They inhibit the action of acetylcholine at muscarinic receptors in the smooth muscle of the airways to bring about bronchodilatation and inhibition of mucus secretion.
Which two surgical responses can be used in the management of COPD
- Bullectomy - large air spaces
- Transplant - only offered in very rare cases.
What is typically present on an x-ray for COPD
- Overinflated lungs with more than 6 ribs visible anteriorly
- Diaphragms low and flat
- The heart to some extend is narrow and stretched.
