Bronchial asthma

Bronchial asthma #Introduction #Pathogenesis of asthma #Classification #Triggers of Asthma #Clinical Features #Diagnosis #PEFR #PFT #Differential Diagnosis #Selection of appropriate inhalation device #Metered dose inhaler #MDI with spacer #MDI with spacer and face mask #Dry powder inhaler

1. BRONCHIAL ASTHMA
IN CHILDREN

2. Introduction
•Bronchial asthma is a disease characterized by
increased responsiveness of the airways to various
stimuli.
•It involve widespread narrowing of the airways which
causes paroxysmal dyspnea, wheezing or cough.

3. Diffuse airway obstruction in asthma is caused by
(i)inflammation of mucous membrane lining the airways,
(ii)excessive secretion of mucus, inflammatory cells and cellular
debris.
(iii)spasm of the smooth muscle of
bronchi.

4. Antigen
Antigen-presenting cells
APCs then "present" pieces of the allergen to otherimmune system T cells
In most people, these other immune cells "check" and usually ignore the
allergen molecules
In asthma patients, however, these cellstransforminto a different type of
cell (th2), for reasons that are not well understood

5. Pathogenesis of asthma

6. Classification
1.Atopic (earlier called extrinsic; IgEmediated, triggered by allergens)
2.Nonatopic (earlier called intrinsic; non-IgEmediated, triggered by
infection)
3.Mixed
4.Exercise induced.
Inhalation of an allergen leads to a biphasic response with early and
late reactions ultimately causing bronchoconstriction.

7. Triggers of Asthma
•Infections
•Exercise
•Weather
•Emotions
•Food
•Endocrine

8. Clinical Features
•Prolonged expiration and wheezing.
•Bouts of spasmodic coughing more in night.
•Child shows air hunger and fatigue.
•Hyper resonant lungs.
•Pulsus paradoxus
•Chest becomes barrel shaped.

10. •Occlusion of bronchi by mucus plugs may result in collapse of small
segments of the lung.
•As obstruction becomes severe, the airflow decreases markedly and
breath sounds are feeble.Wheezing which was earlier audible may
disappear.
•Thus absence of wheezing in presence of cyanosis and respiratory
distress does not suggest clinical improvement.
•During clinical recovery, airflow increases and wheezing may
reappear.

11. Diagnosis
•The diagnosis of asthma is clinical in most cases.
•Recurrent attacks of wheezing or spasmodic cough are highly
suggestive of bronchial asthma.
•Cough, which is associated with asthma generally, worsens after
exercise.
•Sputum is clear and mucoid, but might be yellow due to large
number of eosinophils.

12. PEFR
PEFR = (Ht–100) ×5 + 100
Height in Cms

13. PFT
FEV1,
FVC and
FEV1/ FVC
All being decreased in asthma

14. •Absolute eosinophil counts might help distinguish allergic from infectious
nature of chronic respiratory disease.
•Chest X-ray film shows bilateral and symmetric air trapping in case of
asthma.
•Main pulmonary artery may be prominent in severe cases due to
pulmonary hypertension.
•Allergy tests (e.g. skin test, RAST radioallergosorbentallergen specific lgE)
have limited usefulness.
•Blood IgEmay be raised in children with atopic asthma, but cannot be used
as diagnostic test.

15. Differential Diagnosis
•Bronchiolitis occurs within the first 2 years, usually within the first 6
months of life,
•Usually in winter or spring.
•Generally, there is a single attack.
•Infants with bronchiolitis and atopic dermatitis, high IgElevels or
family history of allergy need follow up for later development of
asthma.

17. •Congenital malformations with obstruction should be excluded in
differential diagnosis.
•Aspiration of foreign body may result in localized area of wheeze,
hyperresonance and reduced air entry.
•Hypersensitivity pneumonitis may follow inhalation of organic dust (molds,
wood, cotton or fur dust, bird droppings, grain) or exposure to specific
agents (epoxy resins, PAS, sulfonamide, nitrofurantoin).
•Cystic fibrosis presents with recurrent wheezing; patients
show clubbing and malabsorption.

18. Following measures may help in reducing risk of recurrences:
i.The bedroom should be clean and free from dust.
ii.Adolescent patients should refrain from smoking.
iii.Exposure to strong odors such as wet paint, disinfectants and smoke
should be minimized.
iv.Cleaning of pet animal as child might be sensitive

22. ANTICHOLINERGIC IN ASTHMA

24. Selection of appropriate inhalation device
Drugs for maintenance treatment can be administered by inhalation or oral route.
The former are more effective, with rapid onset of action and less side effects.
(i)Metered dose inhaler (MDI),
(ii)MDI with spacer,
(iii)MDI with spacer and face mask,
(iv)Dry powder inhaler,
(v)Nebulizer.

25. Metered dose inhaler
•An MDI is a device, which delivers a fixed amount of medication
in aerosol form each time it is activated.
•It is effective but requires considerable coordination, which might
not be possible in young children.
•After actuation, the drug comes out at a pressure and a
significant amount of the drug gets deposited in the oropharynx.

27. MDI with spacer
•Use of spacer inhalation device with an MDI should be encouraged as
it results in a larger proportion of the medication being delivered in
the lung, with less impaction in the oropharynx.
•They also overcome the problems of poor technique and coordination
of actuation and inspiration, which occur with MDI alone.
•Furthermore, use of spacer allows MDI to be used for the young
patient.

29. •MDI used with spacer has been found to be comparable to
nebulizer in delivering salbutamol in acute exacerbation of
asthma in children.
•Spacers have the limitation of being bulky, relatively costly
and cannot be used in young infants and toddlers.
•A homemade spacer (prepared from mineral water bottle)
can effectively deliver salbutamol in acute exacerbation.

30. MDI with spacer and face mask
Attaching a face mask to the spacer facilitates their use in young
infants.

31. THANK YOU