Asthma Flashcards
(24 cards)
What is Asthma?
A chronic inflammatory disorder of the airways characterized by reversible airflow obstruction and resulting in cough, wheeze, chest tightness and shortness of breath
What does asthma cause?
Bronchial hyper responsiveness, constriction of the airways and variable airflow obstruction that is reversible
The fundamental causes of asthma are?
Are NOT understood fully
Stronget risk factors of Asthma?
A combination of genetic predisposition with environmental exposure to inhaled substances and particles that may provoke allergic reactions or irritate the airway
During an asthma attack what happens?
- Bronchial hyperactivity (abnormal sensitivity to normal stimuli by an antigen)
- The smooth muscle cells in the bronchi constrict
- The airways become inflamed (oedema) and swollen
- Increase in mucous production to produce mucus plugs
- Shortness of Breath, Chest tightness, Dry irritating Cough
During an asthma attack Immunoglobulin E (IgE) causes mast cells to degranulate, releasing a large number of inflammatory mediators causing:
Mucosal oedema
Bronchial smooth muscle contraction (bronchospasm)
Tenacious mucous secretion causing airway obstruction
Thickening of airway walls (fibrosis, muscle thickening, remodeling
How is asthma attack managed?
- Immediate administration of oxygen and inhaled beta agonist bronchodilators
- Oral corticosteroids administration early in the course of management
- Careful monitoring of gas exchange and airway obstruction in response to therapy
In Mildest form of asthma what med given?
Short-acting beta-agonist inhalers
In persistent asthma what med given?
Anti-inflammatory medications and inhaled corticosteroids
In severe asthma what med given?
LABA or SABA, ICS
Therapy for reduction of asthma exacerbations:
Immunotherapy * Monoclonal antibodies to IgE
What are Obstructive Lung Diseases?
Characterized by airflow obstruction or limitation. This causes difficulty with expiration
What are Restrictive Lung Diseases?
Characterized by decreased compliance (stretchiness) of lung tissue
RLD lead to?
Leading to reduced lung compliance and decreased lung volumes (lungs are stiff, difficult to expand, whereas airways have normal function
What is RLD caused by?
Pulmonary causes (inflammation and fibrosis of lung tissue), or other causes (e.g. injury or dysfunction of chest wall, obesity)
RLD often affect the?
Alveolar-capillary membrane causing a decrease in diffusion of oxygen
RLD examples?
Interstitial lung Disease, Acute respiratory distress syndrome (ARDS); Fibrosis and Pneumoconiosis (long term exposure to dust e.g. silica, asbestos, coal dust), sarcoidosis, drug-induced lung disease, neuromuscular causes (e.g. chest wall or diaphragm disorders), obesity
What is spirometry?
Measures airflow to determine how much air is inhaled/exhaled and how fast (FVC; FEV1 ; FEV1 /FVC ratio)
What is diffusing capacity?
Measures the ability of lungs to diffuse gas across alveoli
What is residual volume?
Air left in lungs after max expiration,
RV cannot be measured by spirometry but?
Whole body plethysmography’ or Nitrogen washout or Helium dilution)
Diagnosis of COPD is made when the FEV1/FVC ratio is less than?
70%
