Chronic Bronchitis Flashcards
Chronic bronchitis?
Inflammation and obstruction of the airways
Bronchitis?
Inflamed airways
What does chronic indicate in chronic bronchitis?
Persistent coughing for 3 months in a year for 2 consecutive years.
What kind of cough must be present for the Dx of chronic bronchitis?
Productive cough
Etiology of chronic bronchitis?
- Smoking
- Recurrent respiratory infection
In chronic bronchitis, where do histological changes appear first?
In the larger airways
What are the larger airways?
Terminal part of the tracheal and bronchi.
Explain what changes occur in the larger airways.
- Smoking -> hyper secretion of mucus -> to increase secretion you need to increase the number to size of submucosal glands which leads to submucosal gland hypertrophy (which is initially protective but if it is persistent, it will lead to airway obstruction)
Explain what changes occur when the smaller airways are impacted.
Increased # of globlet cells -> hyper secretion -> they will obstruct the airways (r/t hyperplasia) -> Inflammation and fibrosis (the fibrosis tissue is non elastic so you loose compliance) -> compromised gas exchange
Explain the pathology of chronic bronchitis.
Excess mucus -> mucociliary defenses are impaired d/t too much mucus -> traps microbes and debris in airway that cannot be expectorated -> creates a warm, nutritive and moist environment for microbes to proliferate -> infection -> inflammation of the airway walls -> obstruction of the airways because you’re going to have swelling (lumen in compromised) -> airways collapse. -> air trapped in parts of the lung -> decrease alveolar ventilation -> ventilation:perfusion imbalance -> hypoxemia
What will occur as a result of inflammation of the airway walls?
There will be swelling and the lumen will be compromised and airway is obstructed.
What does inflammation of the airway walls indicate at the alveolar level?
At the alveolar level, this means that the alveoli filled with air will perform a gas exchange with the pulmonary capillaries & gas will diffuse into capillaries. This leaves the alveoli empty, but with an obstruction no more air can enter -> this leads to collapse of alveoli.
What does alveolar collapse mean?
There is less surface area for gas exchange and decreased alveolar ventilation because less alveoli are able to participate in gas exchange
What is poor gas exchange a result of?
Decreased air supply to the gas exchange surfaces d/t an obstruction and is NOT d/t a lack of blood flow.
Ventilation: perfusion ratio?
For proper gas exchange, the alveoli must fill with oxygen and blood supply must be sufficient in the pulmonary capillaries
