Respiratory Flashcards
What is the definition and pathophysiology of asthma?
Asthma is the reversible inflammatory disease in response to a trigger. It is characterised by bronchospasm, mucosal oedema and mucus plugging.
Smooth muscle in lungs is exposed to antigens. Leads to mast cell degranulation and release of inflammatory mediators (histamine). Bronchospasm occurs. Increased capillary permeability leads to mucosal oedema and mucous plugging.
What is The definition of COPD?
Chonic obstructive pulmonary disease is a collection of respiratory diseases including chronic bronchitis and emphysema. most commonly found in smokers/ex smokers aged 40years and older.
Describe Chronic Bronchitis.
Chronic Bronchitis is defined as a cough for 3 consecutive months 2 years in a row. It is caused by the inflammation and the bronchioles leading to thickening of bronchioles walls and increased mucous production leading to obstruction of airways. This leads to chronic gas trapping and CO2 retention.
Describe emphysema.
Emphysema is the permanent destruction and enlargement of the alveoli walls leading to decreased elasticity of the lungs. Expiration is normally and passive action therefore the lungs need to be elastic to help push air out when the diaphragm relaxes. In emphysema, lack of elasticity leads to gas trapping and CO2 retention. Pts require the use their accessory muscles to expire air.
Why do we have to be careful how much O2 we give to COPD pts?
Normal people used increased CO2 levels to stimulate the need to breathe. COPD pts retain CO2 chronically causing them adapt and require decreased 02 levels to breathe instead.
What is a pulmonary embolism? And what are the signs and symptoms?
Pulmonary embolism is the occlusion in the pulmonary vascular system often due to a thrombus (DVT). The lungs is ventilating fine but gas exchange annoy occur due to no blood flow. Commonly characterised by low SPO2, SOB, altered conscious state, tachypneoa, and pain which increases which cough/ inspiration.
Describe the respiratory buffer system.
H2O + CO2 = H* + CO3 -
When we retain CO2 it combines with water it produces H* ions which leads to decrease PH leading to acidosis. Expiring CO2 reverses this.
Describe a V/Q mismatch.
V/Q mismatch is when the balance between ventilation and perfusion is compromised. Caused either by a change in ventilation to the lungs or a change in perfusion to the lungs.
Describe the mechanism of breathing.
Pressure inside the lungs is equal to atmospheric pressure outside lungs at rest. Gas travels from higher pressure to lower pressure. Diaphragm pulls out which increases the intrapulmonary volume and decreases the intrapulmonary pressure.. atmosphere pressure is greater than pulmonary pressure causing air to enter lungs. When diaphragm relaxes, the pulmonary volume decreases and causes the pulmonary pressure to increase greater than atmospheric pressure. Gas moves out of the lungs.
What is the definition of tidal volume?
Tidal volume is the amount of air inspired and expired during normal breathing
What is the definition of vital capacity?
Vital capacity is the maximum amount of air that can be expired after maximum inspiration
What is the definition of residual volume?
Is the volume of air remaining in the lungs after maximum expiration.
What is the definition of total lung capacity?
Total amount of gas in lungs after maximum inspiration.
What is the pharynx?
The pharynx is the cavity which connects the nasal cavity and the mouth.
What is the larynx?
The larynx consists of 3 parts.
- Epiglottis- flap which prevents food from entering lungs while swallowing.
- Glottis - vocal chords
- Cricoid- transition from larynx to trachea.
