Respiratory Disease Part 1 and 2 Flashcards
How does air enter the lungs?
Air enters through the trachea, which divides into the right and left bronchi, supplying the right and left lungs. Bronchi divide into bronchioles, which then end in small air sacs called alveoli.
How do the lungs play a role in protecting the body?
(Three main types)
- Sticky mucus substance: Inhaled particles that pass through the nose are trapped by the substance (It also serves to keep the airway moist)
- Cilla: propels mucus and unwanted cells upward where they are coughed out/swallowed.
- Macrophages/Scavenger cells: engulf/destroy inhaled bacteria
What are some measures of pulmonary function?
(Four types)
- Spirometer: Calculate the amount of air the lungs can hold & rate of air exhaled/inhaled
- Impulse Oximetry - Percentage of oxygen
- Gas diffusion - Measures how well oxygen/other gasses pass through air sacs and are absorbed by the blod
- Arterial blood gases (ABG) test - measures acidity, oxygen and CO2 levels from artery, to find out how well lungs can move O2 and remove CO2.
ABG test procedure - https://www.youtube.com/watch?v=m0yFpcqKAm4
How to define asthma?
Definition, causes, and symptoms
- Chronic inflammatory disorder of the airway, primarily immunoglobulin E (IgE) mediated
- Causes recurring episodes of wheezing, breathlessness, chest tightness and coughing
The episodes are assosiated with airflow obstruction
What is the etiology of asthma?
Two types
Name the two types and what causes these asthmas to happen
- Allergic asthma = most common, triggered predominantly by inhaled indoor allergens (dust mite, pet dander, pollen, mold)
- Non-allergic asthma = anxiety, stress, exercise, cold air and other irritants
What is the pathophysiology of asthma?
- When asthma occurs, bronchoconstriction occurs due to stimuli response
- Mucosa is inflamed and edematous, with increased mucus production, resulting in a partially/totally obstructed airway.
Edematous - swollen with an excessive accumulation of fluid.
Clinical Manifestations of Asthma
- Initial symptoms: Cough, Dyspnea
- Signs: Increased respiratory rate, Laboured breathing, hypoxia
Dyspnea - described as an intense tightening in the chest, air hunger, difficulty breathing, breathlessness or a feeling of suffocation.
Definition of COPD
COPD - Chronic obstructive pulmonary disease
Progressive disease that limits airflow either:
1. Bronchitis - inflammtion of bronchial tube lining
2. Emphysema - alveoli destruction
Pathophysiology of Bronchitis
2 types of bronchitis
* Acute - last up to 3 weeks
* Chronic - last about 3 months or more each year/2 years in a row (productive cough and shortness of breath)
- Repeated pollutant exposre (e.g cigaratte smoke)
- Leads to decreased cilia function, increased phagocytosis and suppressed IgA
- Chronic inflammation causes hyperplasia of mucus-secreting cells, resulting in edema
- Airway walls thicken, damaged cilia unable to clean mucus, condusive to bacteria growth, causing respiratory infections.
Clinical Manifestations of Bronchitis
- Decreased air flow
- Dyspnea
- Hypoxemia
- Hypercapnia
Pathophysiology of Emphysema
- Alveoli are damaged (inner wall of alveoli is weaken)
- Larger air spaces created over many small ones
- Surface area reduced, reducing oxygen reaching the bloodstream
- Old air trapped, no room for fresh air
Fresh air contains oxygen-rich air, hence hypoxia may occur
Clinical Manifestations of Emphysema
- Coughing
- Dyspnea
- Increased risk of pneumonia
Pneumonia - Pneumonia is an infection that inflames the air sacs in one or both lungs. The air sacs may fill with fluid or pus (purulent material), causing cough with phlegm or pus, fever, chills, and difficulty breathing.
Definition of Cystic Fibrosis
- Cystic Fibrosis (CF) is caused by abnormal mutation of cystic fibrosis transmembrance conductance regulator gene (CFTR) found on chromosome 7.
- Most comon inherited disease among Caucasian population
- Inherited disorder
- Abnormally thick mucus secretions from epithelial surfaces
- Results in progressive lung disease, pancreatic insufficiency, dysfunction of gastrointestinal and genitourinary systems.
- Genitourinary system - the organs of the reproductive system and the urinary system.
Pathophysiology of CF
- CFTR’s failure results in thick, viscous secretions
- Obstrcution of glands and ducts occur which leads to inability to clear mucus from lungs
- Defective cillia action leads to increased risk infection
- Sometimes, it prevents enzymes from reaching small intestine.
The increased risk of infection is mainly due to Staphylococcus aureus and Pseudomonas aeruginosa.
Symptoms of CF
- Frequent passage of bulky, foul-smelling, oily stools (steatorrhea)
- Poor growth
- Increased amount of sodium and chloride in their sweat, which may lead to increased dehydration risk.
As CF is caused by a faulty gene that controls the movement of chloride and water into and out of cells, people with CF often sweat more than people without the condition, and this sweat contains high levels of chloride, which can crystallise into salt visibly on the skin.
