Respiratory: Asthma Flashcards
What is asthma?
A reversible airflow obstruction
How do you characterise if someone has the inflammatory disease of the airways called asthma?
- Hypersecretion of mucus by bronchial epithelial cells
- Eosinophil infiltration
- Bronchial smooth muscle cells hyperplasia causing airway hyperresponsiveness and bronchospasm
What factors increase the chance of developing asthma?
- Family history of asthma and allergic conditions
- Bronchiolitis as a child
- Exposure to tobacco smoke
- Being born prematurely
- Type of job- occupational exposure
What are the ways asthma is triggered?
- Cigarettes
- Headlice treatment: vapour can irritate airways
- Insecticides and cleaning products
- NSAIDS
- Allergies such as nuts or dairy products
What are the symptoms of an asthma exacerbation (attack)?
Acute or progressive
- Dyspnoea: shortness of breath
- Wheezing: whistling sound during breathing
- Chest tightness
- Cough (occasionally)
- Symptoms WORST at NIGHT and EARLY in the MORNING
What are the airways like when someone experiences an asthma attack?
- Constricted airway
2. Contacted airway of smooth muscle
What is the physiopathology of asthma? (What is the condition of the disease in the lungs like)
- Inflammation
- Hyperplasia (enlargement of organ caused by reproduction rate) of goblet cells
- Hyperplasia and hypertrophy of smooth muscle
- Subendothelial fibrosis (thickening of basal membrane)
- Collagen deposits
How does a severe asthma bronchus compare to a normal bronchus?
- Severe asthma bronchus has a smaller lumen compared to the normal bronchus (restricting airways)
- There’s a lot more production of mucus compared in severe asthma bronchus
How is the asthma mechanism triggered by an allergic reaction (immediate phase)?
- Mast cells are activated by the antigen binding to the mast cell
- Mast cells releases Histamine, Tryptase, Leukotrienes and Prostaglandins
- Leads to Bronchospasms
How does the late phase allergic reaction occur?
- Mast cells are activated by the antigen binding to the mast cell
- Proinflammatory cytokines, chemotactic mediators and chemokines are released which activate the late phase
What is the late phase in an allergic asthma reaction?
- Inflammatory response (airway inflammation and hyperreactivity) occurs
- Factors which do this:
- eosinophil activation
- infiltration of cytokine releasing Th2 cells - Leads to bronchospasm, wheezing, coughing
How can you manage the intermediate and late phase of asthma?
- Intermediate phase:
- Beta 2 agonists
- Theophylline
- Leukotriene Receptors
- Antagonists - Intermediate and Late phase: Glucocorticoids
What does the spirometry test measure? And how can you use the results?
- Forced vital capacity (FVC): Maximal amount of air that can be exhaled after a maximal breath
- Forced expiratory volume (FEV1): volume of air exhaled during the first second of the FVC
- FEV1/FVC at least 70% = normal
When is the spirometry test used?
- Screen for COPD and monitor disease progression
- Differentiating between asthma and COPD
- Diagnosing, evaluating progression and seriousness of lung diseases
- Distinguishing between obstructive and restrictive disorders
- Assessing the extent of abnormalities
- Judging responses to therapy
What does it mean if the results of the spirometry ratio is under 70%?
- Obstructive dis
What are some non pharmacological treatments of asthma?
Avoid environmental, dietary and other triggers of asthma
In terms of asthma management, what is achieving early control?
- Controlling symptoms
- Prevent exacerbations
- Achieve the best possible lung function
How do you remain control in terms of treatment of asthma?
Stepping treatment up and down when necessary