Asthma

Question 1

Define Asthma

Answer 1

chronic inflammatory airway condition-intermittent airway obstruction and hypersensitivity

associated with immune system following an insult in susceptible response, causing variable but widespread obstruction. REVERSIBLE
spontaneously or with treatment

Question 2

Aetiology and risk factors of asthma

Answer 2

Complex multigenic disease
Triggers can be anything from Viral infections (rhino, RSV, flu), bacterial (Myco pneumonia, chlamydia pneumonia), allergens, occupational, chemicals, aspirin,
Th2 mediated allergic response-associated with eosinophils, basophils and macrophages (more present in acute asthma). deposition of eosinophils all around lungs

eosinophil asthma-respond very well to steroids-

eosinophil can be damaging to airway-markers, epithelial damage, mast cells, SMC
several clinical phenotypes of asthma- now becoming important

childhood, eosinophilic-allergic asthma

easinophilic-occupational asthma

adult-obese asthma

non eosinophilic-air pollution, cigarette, infective ashtma

risk factors:
FHx-very strong
Allergen relation
Hx of atopy-eczema/dermatitis/rhinitis

Question 3

Epidiemology of Asthma

Answer 3

variable around the world-china and Vietnam lowest, autralia and Sweden highest

25million in US in 2018-veyr common

Question 4

Signs and Sx of asthma

Answer 4

patients can be any age-but young are common-think of it with youth with SOB

Recurrent episodes of SOB, wheeze, chest tightness, coughing
Hx of having these after irritants (smoke, fumes, cats)
exercise can make it worse
Severe asthmatic-wake up during night with SOB, might use accessory muscle and be constantly SOB
exam-normal, or wheeze on breaths in lungs

Acute exacerbation:-
Hx of poorly controlled asthma+ recent insult decrease from baseline
Triad-cough, breathless, wheeze, 
chest tightness
life threatening: cyanosis, hypotense, exhaustion, low GCS
Silent chest on exam
HR high, resp rate high, arrythmia
FEV<33%
SPO2<92
Hypoxia on ABG, normal CO2

moderate acute ashtma-increasing SOB/wheeze/tightness-
no other features-
FEV 75-50

severe acute asthma
FEV 50%-33%
unable to finish sentence
HR raised, RR raised

Question 5

Investigations of Ashtma

Answer 5

1st time-CXR (infections)-normal, FBC-raised eosinophils and neutrophils

FEV1/FVC ratio-normal should be above 0.75. Asthma have variable results-confirmed if several test varied
also if SABA/SAMA cause an improvement of 12%

Peak flow test-again variable PEF throughout day–over 10%
Or increase by 20% after treatment

acute-
HR rised (higher=worse)
RR rise
ABG-hypxia (under 8) or hypercapnia-life threatening
ECG-arrythmia-life thretening
Peak flow-under 33% of predited-life threatening
33-50-severe
50-75-moderate

Question 6

Management of ashtma

Answer 6

Chronic-
SABA+SAMA is first line
If uncontrolled-use more than 3 times a week, still SOB in sleep etc-
add ICS-repeat
add LTRA (leukotriene receptor antagonist)

then LABA, fixed dose regiment
then can increase ICS dose

acute-02 to maintain above 94%
high dose SABA (salbutamol)-can also use nebuliser
Oral prednisone (iv if can’t take oral)
SABA can also be offered (IPRATROPIUM BROMIDE)
monitor PEF through out
magnesium sulphate can be used if nothing works-ask seniors

Question 7

Complications of Asthma

Answer 7

Chronic-acute exarerbations (moderate/severe/lifethreatening)

airway remodelling-COPD like
Oral candiasis from ICS

Pneumonia (Mycoplasmia pneumonia)

Acute-
Pneumothorax from barotrauma/tension pneumo

Respiratory failure-type 2

Question 8

Prognosis of asthma

Answer 8

Life expectancy is normal
Depends a lot on patient, but use of ICS tends to really help-and stopping them causes relapse

asthma can evolve to be less and less controlled-even if rare

Airway remodelling seems stable after childhood

acute-1400 people died last year from it
poorly controlled asthma is a major risk for it-and it kills