Asthma

Question 1

Define asthma

Answer 1

Asthma is a chronic inflammatory airway disease characterised by intermittent airway obstruction and hyper-reactivity.
It is a disease of small airways with variable expiratory airflow
limitation.
The inflammation is usually reversible, either spontaneously or with
treatment.

Question 2

What is a type 1 hypersensitivity reaction

Answer 2

First exposure to allergen -> immune responses -> igE antibody - plants itself on immune cells such as mast cells
Ar reexposure to this allergen - crossliking og igE antibodies on surface - release mediators such as histamine, leucotrienes, - this is mast cell degranulation
Bronchconstricition then occurs
Inflammation + bronchoconstriction = airway narrowing
This is an acute situation

Question 3

Compare a healthy airway to severe asthma

Answer 3

Ss

Question 4

Descrbe teh typical history for asthma

Answer 4

History
• Cough – dry, nocturnal (more vagal activity)
• Wheeze (audible noise, typically in expiration, thru stethoscope or audible if bad)
• Breathlessness
• Chest tightness

Question 5

Wha are the precipitating factors for asthma

Answer 5

Precipitating factors
• Allergens – pollen, pets
• Dust
• Cigarette smoke
• Cold weather
• Exercise
• Infection
• Aerosols

Question 6

What is the classical presentation of asthma

Answer 6

This leads to the classical presentation of asthma: Examination
• Respiratory Rate
• Pulse
• Oxygen saturations
• Wheeze
• Atopy
• Eczema
Atop Inflammatory response elsewhere in the body - asthma, eczema, hay fever often together

Question 7

How is asthma diagnosed

Answer 7

Ss

Question 8

Compare asthma to copd presentation

Answer 8

ASTHMA
Dry cough Wheeze History of atopy Obstructive Pattern
◦ Good ‘reversibility’

COPD
Productive cough Wheeze
History of smoking Obstructive Pattern
◦ Poor ‘reversibility’

Question 9

What does the management of asthma depend on

Answer 9

Clinical judgement! The management depends on the probability of asthma:

• High Probability - have classic features
• Start on treatment
• Low Probability
• Investigate/rule out other causes
• Refer for further investigations
• Intermediate probability
• Spirometry with reversibility testing

Question 10

Describe 1o and 2o prevention

Answer 10

PRIMARY PREVENTION Evidence is lacking
• Avoidance of potential triggers in
pregnancy/childhood
Pharmacological - first exposure COUKD happen antenatally???

SECONDARY PREVENTION Remove triggers (if possible)
• Pets
• Dust
• Smoke
• Occupational
• Vaccination

Question 11

Decsribe the stepwise management for adults

Answer 11

Low dose inhaled cortico steroid, short acting b2 agonist - salbutamol - then long acting b2 agonist

Question 12

Describe stepwise management for children

Answer 12

Ss

Question 13

What are different types of inhalers

Answer 13

Blue - reliever - salbutamol
Brown - reventer - ICS
Orange - preventer + green symptom controller (salmeterol) = purple seretide?

Question 14

How is asthma managed in an emergency

Answer 14

Oxygen!
Short acting Beta 2 agonist
(Salbutamol - nebuliser)
Steroids (Prednisolone or hydrocortisone)
ADMIT!
Consider adding other medications
GP follow up after discharge
Consider CXR to rule out pneumothorax

Question 15

Descrbe the difference between acute sever are life threatening asthma

Answer 15

Acute severe: Cant finish sentence, wheeze, hypoxiia but typically >92%, high respiratory rate >= 25, HR >= 110
Life threatening: sillent chest, altered consciousness, go into coma?, central cyanosis, reduced effort, lowered Bohr, o3 <92%, of ,33%