Asthma Flashcards
(51 cards)
definition of asthma (long)
a chronic (long term condition which can be managed and not cured) inflammatory disorder of the airways. It involves complex interaction between many cells e.g. eosinophils, mast cells and inflammatory mediators such as leukotrienes that result in inflammation, obstruction, and hypersensitivity.
traits of it
- Reversible obstructive airway disease
- Chronic Inflammatory disease
- Bronchial hypersensitivity
what part of the body does asthma affect
Asthma affects the airways
what does it cause the airways to do
narrow and swell
what does narrowing of airways cause
resulting in wheezing and difficulty breathing
where does air move during breathing
air goes nose → upper airways → windpipe → two large bronchi → lungs
what are the lungs protected by
lungs = protected by ribcage
what are the airways like in asthmatic patients
In asthma, the airways are sensitive, and may have triggers
examples of triggers in asthma
e.g. inflammatory =. dust. but for others, can be due to laughter, stress etc , irritants like cold air
what does an asthmatic trigger do
As asthmatic trigger causes the airways to swell, and the muscles around to contract. The airways narrow, and breathing through them makes the wheeze sound. mucus is produced and clogs up the airways, making it harder to breathe.
- narrowing of airways is reversible if
the trigger is removed or inflammation is medically cured
what happens when allergens hit the system
histamines and prostaglandins release when the allergens hit the system
what receptors in the airway are targeted
receptors like the beta 2 receptors and muscarinic in the airways are to be targeted
Symptoms of Asthma
- Variable & intermittent symptoms:
- Coughing
- Expiratory Wheeze (problem breathing out)
- Shortness of breath (dyspnoea)
- Excess mucus production
- Chest tightness
- Hyperinflated chest
- Symptoms worse at night and in the early morning, symptoms in response to exercise, allergen exposure and cold air, symptoms after taking aspirin or beta blockers
diagnosis of asthma diagram (order of tests and interpretation of results)
https://www.notion.so/clinical-aspects-1e800bb3982d80309f23df013c6af87f?pvs=4#1e800bb3982d805ab40dca7a469e0543
how many tests for asthma
4
what are the tests (in order)
- blood (eosinophils) test (often higher levels of this in patients)
asthma patients more likely to have hayfever or high blood pressure too (eotopic triad)
- bronchodilator reversibility
- peak expiratory flow variability
- bronchial challenge test
Pulmonary Function Tests: Spirometry
A spirometer can give you a number of readings
- FVC (Forced Vital Capacity) -
- FEV1 (Forced Expiratory Volume in 1 Second) –
- FEV1/FVC -
- FVC (Forced Vital Capacity) -
This is the total volume of air expired after a full inspiration.
FEV1 (Forced Expiratory Volume in 1 Second) –
This is the volume of air expired in the first second during maximal expiratory effort.
- FEV1/FVC -
This is the percentage of the vital capacity which is expired in the first second of maximal expiration.
In healthy patients the FEV1/FVC is usually above ?
70% - should be 100%:
- in asthmatics ?
88% or lower
Why do we use spirometry
- Spirometry provides an objective assessment of airflow obstruction and is important in staging asthma severity.
- Patients with asthma tend to show reversibility after administration
when should spirometry be done
- It should be done on initial diagnosis of asthma, after treatment is started and symptoms have stabilised, and every 1 to 2 years afterward.
- Spirometry measurements are usually done before and after administration of a beta-2 agonist.
