Bronchial asthma is a chronic condition characterized by reversible inflammation and airway hyper-responsiveness, leading to symptoms such as wheezing, breathlessness, and coughing. Diagnosis includes lung function tests and measures of airway inflammation and hyperreactivity, while management focuses on controlling symptoms and preventing exacerbations through reliever and controller medications. Special considerations are necessary for asthma during pregnancy and in the context of COVID-19, including the importance of maintaining prescribed medication and having a written asthma action plan.

1. Dr P Mayurathan

2. Bronchial Asthma
• The chronic reversible inflammation is associated with
airway hyper responsiveness that lead to recurrent
episodes of wheezing, breathlessness, coughing and
chest tightness
• Symptoms occur mainly at night or in the early morning
• Episodes are associated with widespread and variable
airway obstruction within the lungs which is often
reversible either spontaneously or with treatment

5. Risk factors/triggers for Asthma
Host factor
• Genetic
• Obesity
• Sex
• Below 14: Males > females
• Adulthood: Females > males
Environmental factor
• Allergens
- pollens
- house dust mites
• Infections
• Occupational
sensitizers
• Tobacco smoke
• Diet
• Drugs
• Cold air
• Exercise

6. What is atopy?
• Atopy is defined as the tendency to be allergic and/or intolerant
to many substances
• It is the medical term used to describe a particular group of
patients with a genetic predisposition to allergies
• It is the tendency to produce an exaggerated IgE immune
response to otherwise harmless environmental substances
• Atopy may have a hereditary component, although contact with
the allergen or irritant must occur before the hypersensitivity
reaction can develop

7. Pathophysiology of Asthma
Allergens and Triggers
Inflammation
Airway hyper-responsiveness
Symptoms
Cough
SOB
Wheeze
Chest tightness

8. Pathophysiology of Asthma

9. Pathophysiology of Asthma

10. Triggers
Pathophysiology of Asthma

11. • Limitation of airflow
– is due mainly to bronchoconstriction
– but airway edema, vascular congestion, and luminal
occlusion with exudate may also contribute
• This results in a reduction in
– Forced expiratory volume in 1 s (FEV1)
– FEV1/FVC
– Peak expiratory flow (PEF)
• Increased in airway resistance
Pathophysiology of Asthma

12. Diagnosis of Asthma

13. Lung Function Tests
• Spirometry
– FEV1/FVC ratio of less than 70%
• Bronchodilator reversibility (BDR)
– Offer a BDR test to patients with obstructive spirometry
– improvement in FEV1 of 12% or more, together with an increase
in volume of 200 ml or more is considered as a positive test
• Peak expiratory flow variability
– Regard a value of more than 20% variability as a positive test
Diagnosis of Asthma

14. Airway inflammation measures
• Fractional exhaled Nitric Oxide [FeNO]
– FeNO level of 40 parts per billion (ppb) or more as a positive test
for adults (aged 17 years and over)
– FeNO level of 35 ppb or more as a positive test for children and
young people (aged 5 to 16 years)
Airway hyperreactivity measures
• Direct bronchial challenge test with histamine or methacholine
– Regard a PC20 value of 8 mg/ml or less as a positive test
{PC20 - provocative concentration causing a 20% drop in FEV1}
Diagnosis of Asthma

15. Other supportive investigations
• FBC – Elevated eosinophil count
• CXR – Normal initially

16. How to check the peak flow variability easily?
• Do the Peak Flow assessment before and after
salbutamol nebulisation

17. Spirometry

18. Differential diagnosis of Asthma
• COPD
• Left ventricular failure
• Upper airway obstruction and inhaled foreign bodies
• Gastro oesophageal reflux disease (GORD)
• Vocal cord dysfunction
• Eosinophilic pneumonias
• Systemic vasculitis - Churg-Strauss syndrome and
polyarteritis nodosa

19. Classification of Asthma
Old Classification
• Intermittent Asthma
• Mild persistent Asthma
• Moderate persistent Asthma
• Severe persistent Asthma
New Classification
• Controlled Asthma
• Partially controlled Asthma
• Uncontrolled Asthma

20. New classification
Level of Asthma Control
Characteristic Controlled
(All of the following)
Partly controlled Uncontrolled
Daytime symptoms Twice or less/week More than twice/week Three or more
Features of partly
controlled asthma
present in any
week
Limitations of
activities
None Any
Nocturnal symptoms
/awakening
None any
Need for
reliever/rescue
treatment
Twice or less/week More than twice /week
Lung function Normal <80% predicted

21. Aims of Asthma Management
• Minimal (ideally no) chronic symptoms, including nocturnal
• Minimal (infrequent) exacerbations
• No emergency visits
• Minimal (ideally no) use of as-required β2-agonist
• No limitations on activities, including exercise
• PEF circadian variation <20% and (Near) normal PEF
• Minimal (or no) adverse effects from medicine

22. Medications to treat asthma can be classified as;
• Relievers
– They are used on as needed basis, that act quickly to
reverse bronchoconstriction and its symptoms
• Controllers
– They are medications taken daily on a long term basis
to keep asthma under clinical control chiefly through
their the anti inflammatory effect.

23. Reliever Medications
• Rapid acting inhaled β2 agonist
• Anti cholinergics
• Short acting Theophylline
• Short acting oral β2 agonist (not used commonly)

24. Controller Medications
• Inhaled Glucocorticoids
• Long acting inhaled β2 agonist
• Long acting oral β2 agonist
• Leukotriene modifiers
• Systemic glucocorticoids
• Sustain release Theophylline
• Cromones
• Anti IgE antibody
• Allergen specific immunotherapy. Eg. Mepolizumab (anti-interleukin 5)

25. Brittle Asthma
• Chaotic variations in lung function despite taking
appropriate therapy
• The most effective therapy is subcutaneous epinephrine

26. Pregnancy and Asthma
• Severity during pregnancy
• 1/3 - improve
• 1/3 - unchanged
• 1/3 - worse
• Poor control can have adverse effect to fetus
• short-acting β2-agonists, ICSs, theophylline ,leukotriene modifiers
(montelukast) are not associated with fetal abnormalities
• Acute exacerbation should be treated aggressively to avoid fetal
hypoxia
• During labour-no special indication for LSCS other tan Obs indication

27. Asthma and Covid-19
• Advise patients with asthma to continue taking their prescribed asthma
medications, particularly ICS oral corticosteroids (OCS) if prescribed
• Make sure that all patients have a written asthma action plan
• Where possible, avoid use of nebulizers due to the risk of transmitting infection
to other patients and to healthcare workers
• Avoid spirometry in patients with confirmed/suspected COVID-19
• Follow infection control recommendations if other aerosol-generating
procedures are needed
• Follow local health advice about hygiene strategies and use of personal
protective equipment, as new information becomes available in the country or
region

28. Discharge plan
• Minimum 7 days course of oral steroids along with
continuation of bronchodilator therapy
• Short acting β2 agonist can be used as needed
• Initiate or continue inhaled glucocorticosteroids
• Factors precipitated the exacerbation should be identified an
strategies for future avoidance implemented
• Satisfactory inhaler and peak flow meter techniques should be
assessed and confirmed

29. • Providing a short course of oral steroid to be on hand for
subsequent exacerbations
• Written action plan-according to the PEFR
• If <400l/min-2-4 fold increase inhaled steroids
• If <300l/min-take oral steroids
• If<200l/min-hospital admission
• The follow-up appointment should be arranged within few
days
Discharge plan

30. What are the clinical and social significance of
asthma?

31. 1. T/F regarding Bronchial Asthma?
1. Associated with Type 1 hypersensitivity reaction
2. Basophils, mast cells and eosinophils play an important
role
3. Irreversible airway obstruction occurs
4. Common among developing countries than developed
countries
5. Socio-economic consequences of asthma is not significant
when comparing to the clinical significance

32. 2. T/F regarding discharge plan of asthma patient;
1. Can be discharged while on regular salbutamol
nebulization
2. Ensure the patient has oral corticosteroids
3. Review and correct the inhaler technique
4. Risk factor assessment should be done only during the
clinic review
5. Plan of next clinic review should be arranged

33. 3. T/F regarding asthma and pregnancy;
1. 1/3rd of the patients develop frequent exacerbations
2. Leukotriene receptor antagonists are contraindicated
3. Oral corticosteroids can be given during breat feeding
4. LSCS is contraindicated
5. Mepolizumab (anti-interleukin 5) is safe