Asthma Flashcards
clinical presentation of asthma
cough, wheeze, shortness of breath, sputum, chest tightness
signs of asthma
- hypoxia
- wheezing
risk factors of asthma
- family history
- associated with other allergic conditions eg allergic rhinitis
- allergens in the air
when are asthma symptoms worse?
early in the morning and late at night
investigations for asthma
- peak flow
- spirometry (also with the use of a nebulised SABA to determine reversibility)
- blood gases
- chest radiography (exclude underlying disease)
- bronchoprovocation test (done when the patient has word-induced asthma)
- skin prick (check for allergens)
- pulse oxymetry
asthma vs COPD
asthma has an element of reversibility (cut off at 12% on PFTs)
treatment of asthma
- SABA prn
- low dose ICS + SABA prn
- medium dose ICS and SABA prn
- high-dose ICS, SABA/formoterol prn
- Anti-IgE/Anti-IL5/Macrolides, SABA/formoterol prn
if the patient’s asthma approves, what can you do?
you can step down on treatment i.e. decrease the dose or remove drugs altogether
where can leukotriene receptor antagonists be used?
From step 2 asthma onwards
management of an asthma exacerbation
- investigations: peak flow,
- treatment using salbutamol 5mg in nebulised form and IV steroids and bronchodilator eg ipratropium bromide i.e. SAMA
- give oxygen if the spo2 is lower than 94%
if the drug does not work and the patient has chest tightness, what do you do?
swap the bronchodilator to magnesium sulfate because this has bronchodilator properties
if the patient’s asthma is as bad as needing ITU, how do you manage?
give IV salbutamol rather than rebulised salbutamol
what can cause or worsen asthma?
- gestational asthma (can remain the same, be better or worsen)
- occupational (work-exacerbated or work-induced)
- reflux disease worsens asthma control
- can be exacerbated due to respiratory tract infections
type 1 vs type 2 pneumocytes
type 1: gaseous exchange
type 2: produces surfactant; synthesises substances such as fibronectin and alpha-1-antitrypsin
asthma increases which value in PFTs?
residual volume
how would you diagnose asthma?
pulmonary function tests
examples of obstructive lung disease
- chronic bronchitis
- emphysema
- asthma
- bronchiectasis
- small-airway disease
- bronchiolitis
characteristics of asthma
- episodic bronchoconstriction due to increased airway sensitivity to a variety of stimuli
- inflammation of the bronchial walls
- increased mucus secretion
histopathology of asthma
- increased mucosal goblet cells and submucosal glands
- thickened basement membrane
- bronchial smooth muscle hypertrophy
- airway wall oedema
- curschmann spirals
- eosinophils
- extracellular charcot-leyden crystals
characteristics of acute severe asthma
- state of unremitting attacks
- long history of asthma
- may prove fatal
types of asthma
atopic: evidence of allergen sensitisation and immune activation (have allergic rhinitis and eczema)
- childhood-onset; type I hypersensitivity reaction
non-atopic: no evidence of allergen sensitisation
triggers for bronchospasmic episodes
- respiratory infections
- exposure to irritants
- cold air
- stress
- exercise
- drugs eg aspirin
what about non-atopic asthma?
- no evidence of allergic sensitisation
- less likely to have a positive family history
- skin pricks are negative, usually
- commonly triggers by RTIs or air pollutants
drug-induced asthma?
- aspirin-sensitive asthma
- sensitive to small doses of it
also experience urticaria
presnt with recurrent rhinits and nasal polyps
