ASTHMA

1. ASTHMA
DR. KABIRU SADA BELLO FMCP

2. OUTLINE
• Definition
• Epidemiology
• Pathogenesis
• Precipitants
• Clinical features
• Classification of severity
• Investigations
• Complications
• Treatment
• Prevention of attacks
• Differential Diagnosis

3. Definition
• A chronic inflammatory disease of the airways,
characterized by spontaneous, variable and
recurring symptoms of breathlessness,
wheezing, chest tightness, reversible air flow
limitation and bronchospasm.

4. EPIDEMIOLOGY
• Age of onset 3-5 years (Extrinsic), Middle age
(intrinsic)
• Commoner in developed countries
• Affect 10% Nigerians
• Affect 300 million people world wide, expected
to rise to 400 million by 2025.
• Over 250,000 persons world wide die from
asthma a year
• 80% of asthma death occurs in low income and
middle income countries

5. AETIOLOGY
• Underlying cause of asthma still largely unknown.
• Thought to arise from interplay of Genetic and Environmental
factors.
- Polymorphic Variation of IL 4/ 13 Genes
- Chromosome 5q31-33, 20p13
• Hygiene Hypothesis
• Such factors induce chronic inflammation of the airways causing
hyper-responsiveness and bronchoconstrition.

6. PRECIPITANTS
• Allergins: Pollen, Pets,
• Irritants dust, Vapour and Perfumes
• Environmental Pollution: fire wood smoke,
Sulphur dioxide, Ozone, Ciggarate smoking,.
• Viral Infections: Rhinoviruses, Parainfluenza,
Resp syncithial virus.
• Emotion
• Cold Air
• Drugs: β blockers, NSAIDS
• Occupational sensitizers:

7. PATHOGENESIS

8. CLINICAL FEATURES
• Difficulty in breathing
• Chest tightness
• Wheezing
• Rhonchi
• ±Cyanosis

9. CLASSIFICATION OF SEVERITY
Parameter Mild Moderate Severe
Imminent
respiratory
failure
Breathlessness Can walk or lie
down
Speech &
alertness
Sentences
Agitation: + or -
Phrases
Agitation usual
Words
Agitated
Drowsy or
confused
Respir. rate Increased Increased Often > 30/min Paradoxical
Accessory
muscles &
suprasternal
recession
Usually not Usual Usual
Paradoxical
chest and
abdominal
movement
exhaustion
Pulse rate >100 100-120 >120 Br adycardia
arrythmias

10. INVESTIGATIONS
• FBC, Sputum M/C/S: Oesonophilia
• CXR- Hyperinflation (During attacks/ Chronic
Asthma)
• Lung function tests:
- PEFR
- FEV1 : 15% improvement after taking
bronchodilators.
• Skin test for allergy:
• Trial of corticosteroids

11. PEAK FLOW METRE AND GRAPH

12. SPIROMETRE

13. TREATMENT
• Bronchodilators:
- β2 agonist: Short and long acting
- Anticholinergics
- Thiothanxanthes: Aminophyline, Thiophyline
• Steroids
• Leuco trienes inhibitors
• Antibiotics
• Oxygen

14. INHALERS

15. NEBULIZER

16. STEPWISE MANAGEMENT
STEP PEFR TREATMENT
1. Occasional symptoms,
less frequent than daily
100% predicted As-required short-acting
b2 agonists
If used more than once
daily, move to step 2
2. Daily symptoms ≤ 80% predicted Regular inhaled preventer
inhaled steroids up to 800
μg daily.
3. Severe symptoms 50–80% predicted Inhaled corticosteroids
and long-acting inhaled b2
agonist
4. Severe symptoms
uncontrolled with highdose
inhaled
Corticosteroids
50–80% predicted High-dose inhaled
corticosteroid and regular
bronchodilators
5. Severe symptoms
Deteriorating
≤ 50% predicted Regular oral
corticosteroids
6. Severe symptoms
deteriorating in spite of
≤ 30% predicted Hospital admission

17. PREVENTION OF ATTACKS
• Control of extrinsic factors
• Steroids
• Mast cell stabilizers: Sodium Chromoglycate

18. DIFFERENTIAL DIAGNOSIS
• Acute Pulmonary Oedema (Cardiac Asthma)
• Chronic Obstructive Airway disease
• Inhaled foreign body
• Bronchopulmonary allergic aspergillosis
• Bronchiolitis (Children)

19. CONCLUSION
• Bronchial Asthma is a common respiratory
disease that present with recurrent dypnea,
chest tightness and wheezing.
• It occurs due to genetic predisposition and
environmental factors.
• β agonist, anticholinergics and steroids are the
main stay of treatment.