Asthma

Question 1

Definition

Answer 1

Chronic inflammatory condition of the airways

Involves hyper-responsiveness to certain triggers

Question 2

Pathological characteristics

Answer 2

Infiltration of mucosa with inflammatory cells (esp eosinophils)
Mucosa odema with basement membrane thickening
Damaged mucosal epithelium
Hypertrophy of mucous glands with increased secretion
Smooth muscle contraction (secondary to inflammation)

Question 3

How do most children present?

Answer 3

Usually with cough

Usually at 2-7 years of age (most children will be free of asthma by puberty)

Question 4

Goals of asthma management?

Answer 4

Prevention of acute attacks. Acute attacks represent failed therapy

Question 5

Cornerstone treatment?

Answer 5

Inhaled corticosteroids (‘preventers’)
Salbutamol (SABA)
Should not smoke***

Question 6

Drugs that can exacerbate asthma

Answer 6

Beta blockers, Aspirin, NSAIDS

Question 7

Key clinical features

Answer 7

Wheeze
Cough (esp nocturnal)
Tightness in chest
Breathlessness

Question 8

Major trigger factors for asthma

Answer 8

A - allergens
B - Bronchial infection
C - Cold air, exercise
D - Drugs –> aspirin, NSAIDS, B-Blockers
E - Emotion - stress, laughter
F - Foods –> MSG, nuts, seafood
G - GORD
H - Hormones –> pregnancy, menstruation
I - Irritants - smoke, perfumes, smells, etc
J - Job –> wood dust, flour dust, animals, etc

Question 9

Key investigations and results for asthma

Answer 9

Measurement of peak expiratory flow rate PEFR –> Variations of values over time

Spirometry is most accurate test. Use in childre >6yo and adults. FEV1/VC ratio 15% improvement

Inhalation challenge tests. Sometimes useful to confirm diagnosis. Airway reactivity tested via inhalation of histamine.

Exercise challenge may be useful

Allergy testing

CXR - not routine, but used if complications exist or if sx not explained by asthma.

Question 10

Definition of well controlled asthma?

Answer 10

1. No cough, wheeze or breathlessness most of the time
2. No nocturnal waking due to asthma
3. No limitation of normal activity
4. Good exercise ability
5. Minimal need for SABA
6. No severe attacks

Question 11

What are the grades of asthma severity?

Answer 11

Intermittent:
Episodic sx < weekly; noctural sx weekly but not every day; Nocturnal sx >2 monthly; sx regularly with exercise

Moderate persistent:
Daily sx; Nocturnal sx > weekly; several known triggers apart from exercise

Severe persistent:
Daily sx; Frequently wakes with cough/wheeze; Chest tightness on walking; Limitation of physical activity

Question 12

When should ICS be sued in asthma?

Answer 12

For anyone with Mild persistent, moderate persistent and severe persistent asthma

For anyone with intermittent asthma whom use SABA 3+ times/week

Question 13

Therapy in mild intermittent asthma?

Answer 13

SABA prn

as long as using SABA < 3 times / week

Question 14

First line therapy in all grades of asthma severity, aside form mild intermittent type?

Answer 14

Regular ICS plus Inhaled B-agonist

PLUS

Prophylactic use of SABA prior to exercise or known triggers

Question 15

Second line therapy in all grades of asthma severity, aside from mild intermittent type?

Answer 15

If control inadequate, increase ICS dose
OR try theophyline derivitive or leukotriene antagonist

For exacerbations: Oral prednisolone course

(Can also consider anti-IgE agents)

Question 16

Early warning signs of impending asthma attack / severe asthma

Answer 16

Sx persisting or worsening, despite adequate medication
Increased coughing / chest tightness
Poor response to 2 inhalations
Benefit from meds no lasting 2 hours
Increasing medication requirements
Disturbed sleep due to coughing / wheeze / breathlessness
Chest tightness upon waking in morning
Low PEFR readings

Question 17

Outline the asthma first aid action plan

Answer 17

1. Sit upright & remain calm
2. Take 4 separate puffs from reliever puffer (one puff at a time)
3. Wait 4 mins
4. If no improvement, take another 4 puffs (4x4x4 rule)
5. If lottle or no improvement from these dosages, call an ambulance (000 or 112 mobile)
6. Comtinue taking 4 puffs every 4 mins until ambulance arrives

See your doctor immediately after a serious asthma attack