Respiratory Disorders

1. Dr Swati Prashant MD Paediatrics www.paeditrics4all.com drprashantw@gmail.com Index Medical College ,indore,MP,INDIA Respiratory Disorders by dr swati prashant MD. drprashantw@gmail.com

2. Bronchiolitis • Acute Bronchiolitis is one of the common serious acute respiratory infections in infants . • Age----- 1-6 months is the common age , rarely affected till 2 yrs . • Season--- Winter & Spring seasons are common . • Causative Organism---- RSV IN > 50% cases. by dr swati prashant MD. drprashantw@gmail.com

3. Bronchiolitis • Other organisms include, • Para influenza 3,1 & 2 • Adenovirus • Influenza Viruses & • Mycoplasma Pneumonia . by dr swati prashant MD. drprashantw@gmail.com

4. Pathogenesis • Bronchioles are involved. • Inflammationof bronchiolar mucosa leads to Edema , thickening , formation of mucus plugs & cellular debris . • Bronchiolar spasm is rare . • Small lumen + Inflammation + mucus causes further obstruction , airway resistance & ↓ airflow . by dr swati prashant MD. drprashantw@gmail.com

5. Bronchiolitis • Resistance is both during inspiration & expiration . • Obstruction → air trapping in alveoli . This leads to Emphysema & later Atelectasis . • If child’s body compensate then there is ↑ Ventilation ( hyperventilation of normal alveoli ) . by dr swati prashant MD. drprashantw@gmail.com

6. Bronchiolitis • If the body do not compensate then after Atelectasis there is further hypoxemia & CO 2 retention. This causes Respiratory Acidosis . by dr swati prashant MD. drprashantw@gmail.com

7. Clinical Features • URI followed within a few days by fast breathing . • ICR • Panting for breath & cyanosis . • Fever is moderate . • Accessory muscles of respiration are working . • Expiration is prolonged . by dr swati prashant MD. drprashantw@gmail.com

8. Bronchiolitis • Respiratory distress is out of proportion to the physical signs of the lungs . • Emphysema due to air trapping pushes Liver & Spleen down . • Over inflated chest , ↑ AP diameter • Hyper resonance noted on percussion . by dr swati prashant MD. drprashantw@gmail.com

9. Investigations • X-RAY Chest— • Hyperinflation ( translucent) + infiltrates . • Diaphragm pushed down . • WBC ---N to ↑ . • Nasopharyngeal aspirate taken to identify RSV BY MONOCLONAL ANTIBODY TEST . by dr swati prashant MD. drprashantw@gmail.com

10. D/D 1 . Bronchial Asthma--- - Unusual < 1 year - F/H-- + - Several attacks / Year - May occur without preceding respiratory infection. - Responds to Bronchodilation . by dr swati prashant MD. drprashantw@gmail.com

11. Bronchiolitis • 2) CCF— • Cardiomegaly , Tachycardia , Large tender Liver , ↑JVP , Edema & basal crepitations . • 3) F .B In Trachea --- • H/O aspiration , localized wheeze , s/o Collapse , localized Emphysema . by dr swati prashant MD. drprashantw@gmail.com

12. Bronchiolitis • Bacterial Pneumonia s/o obstruction are less High fever Crepts . by dr swati prashant MD. drprashantw@gmail.com

13. Treatment • Symptomatic • 1) Humid atmosphere. • 2) Sitting posture or semi reclined . • 3) Oxygen ( humidified ) . • 4) Fluids & Electrolytes restored . • 5) PaO2 maintained to 95 % or more . • 6) Antibiotics no role . by dr swati prashant MD. drprashantw@gmail.com

14. Bronchiolitis • 7) Antiviral agents • Ribavirin given through Nebulizer is of some use . • β 2 Agonists & Ipratropium in > 6 months old . • CPAP to control respiratory failure . • Prognosis----generally it is self limiting . by dr swati prashant MD. drprashantw@gmail.com

15. Bronchial Asthma • Also called as Childhood Asthma or Allergic Bronchitis . • Definition ---- • It is defined as the ↑ed responsiveness of the Trachea & Bronchi to various stimuli . • MANIFESTS AS WIDESPRED NARROWING OF THE AIRWAY CAUSING dyspnea , Wheezing or cough . by dr swati prashant MD. drprashantw@gmail.com

16. Bronchial Asthma • It is reported in 4- 20 % of school children . • Disturbed sleep restricted activity and school absenteeism . by dr swati prashant MD. drprashantw@gmail.com

17. Pathophysiology • Airway obstruction is caused by • 1) Edema & Inflammation of the mucosal lining . • 2) Excessive secretions • 3) Spasm of smooth muscle of Bronchi . by dr swati prashant MD. drprashantw@gmail.com

18. Classification • According to causes . • 1) Extrinsic : ( Ig E mediated , triggered by Allergens ) . • 2) Intrinsic : ( Non IgE mediated ) triggered by infections . • 3) Mixed • 4) Exercise induced . • 5) Drug induced ( Aspirin ) . by dr swati prashant MD. drprashantw@gmail.com

19. Classification ctd. • Classification of Asthma acc. To severity by dr swati prashant MD. drprashantw@gmail.com

20. Bronchial Asthma • Asthmatic attack is divided into 2 phases • Early Phase : • Starts within 10 min . Of exposure . • Characterised by release of Histamine , Leukotriens C , D & E , Prostaglandins etc from Mast cells . • Allergens + Ig E bound mast cells → realease the above substances . by dr swati prashant MD. drprashantw@gmail.com

21. Bronchial Asthma • These substances cause: • Bronchoconstriction • Mucosal edema • Mucus secretions ----obstruction . • This phase is inhibited by β 2 agonist drugs . by dr swati prashant MD. drprashantw@gmail.com

22. Bronchial Asthma • Late phase : • Develops 3-4 hrs later with peak at 8-12 hrs . • Again there is a release of mast cell mediators . • This phase I prevented by STEROIDS . • This phase is typically clinical asthma . by dr swati prashant MD. drprashantw@gmail.com

23. Bronchial Asthma • Airway resistance is more during expiration because airways close prematurely . This cause Air trapping + hyperinflation + dyspnea + hypo perfusion → Pa o 2 ↓ . • Initially to compensate the remaining part of the lung hyperventilate causing co2 wash out -> PaCO2 ↓ . by dr swati prashant MD. drprashantw@gmail.com

24. Bronchial Asthma • But later as obstruction becomes severe • ↓ • hypoventilation • ↓ • CO2 retention • ↓ • PaCO 2 ↑ • causing Acidemia by dr swati prashant MD. drprashantw@gmail.com

25. Bronchial Asthma • Why there is bronchial reactivity ? • 1) Abnormal airways • 2) abnormal neural conduction of airways • 3) Bronchial inflammation . • 4) Imbalance between excitatory & Inhibitory mechanisms ( cholinergic & α adrenergic v/s β adrenergic & non adrenergic ) . by dr swati prashant MD. drprashantw@gmail.com

26. Triggers of Asthma • 1)Allergy : Inhaled environmental & aeroallergens ---house dust , mites , industrial allergens , smoke , • 2) Drugs ( Aspirin , NSAIDS ) • 3) Viral infections : common in young children eg. RSV . • 4) Exercise : genetic ,heat & water loss causes hyperosmolarity --- this stimulates mediators from mast cells . by dr swati prashant MD. drprashantw@gmail.com

27. Bronchial Asthma • 5) Weather change : loss of heat , aeroallergens . • 6) Emotional factors : emotional stress operated through Vagus , initiating bronchial smooth muscle to contract . • 7) Role of Food : • 8) Endocrine factors : endocrinal changes during Puberty the chances of asthma . by dr swati prashant MD. drprashantw@gmail.com

28. Clinical Features • Reccurent cough , cold , wheezing , dyspnea , sweating , fatigue , accesory muscles working , hyperresonant chest , cyanosis ,sputumm clear . • Investigations : CBC , AEC , Xray chest , PFT , Allergy test . by dr swati prashant MD. drprashantw@gmail.com

29. D/D • 1) Bronchiolitis • 2) Congenital malformations : vascular rings , cysts , larngomalacia • 3) F.B aspiration • 4) Pneumonitis • 5) Cystic Fibrosis by dr swati prashant MD. drprashantw@gmail.com

30. Treatment • Life threatening Asthma : • O 2 , • S/C Adrenaline , Terbutaline • Inhalation : Salbutamol/ Terbutaline + Ipratropium bromide • I/V Hydrocortisone 10 mg / kg • Shift to ICU • If improves ---inhalation every 20—30 mn. + Hydrocortisone every 6-8 hourly . by dr swati prashant MD. drprashantw@gmail.com

31. T/t of moderate Asthma • 1) Inhaled β 2 agonist every 20-30 min + o2 + oral Prednisolone 1 mg / kg . • 2) if improves give inhalation 4-6 hourly + oral Prednisolone 7 days . • T/t Mid asthma • Inhalation by nebuliser MDI 10-20 PUFFS IN 20 MIN ---IF improves sent home . by dr swati prashant MD. drprashantw@gmail.com

32. Long Term management • Avoid triggers • Drug therapy • Parent education • Pharmacotherapy : Bronchodilators , steroids , Mast cell stabilisers , Leukotriene modifiers , Theophylline , IMMUNOTHERAPY by dr swati prashant MD. drprashantw@gmail.com

33. Bronchodilators : provide immediate relief • Short acting : Salbutamol , Terbutaline , Adrenaline . • Long acting : Salmeterol , Formoterol . • They relax the smooth muscles , act on β2 receptors . by dr swati prashant MD. drprashantw@gmail.com

34. Steroids : potent antiinflammatory agent • They inhibit cytokine production • They ↑synthesis of β adrenergic receptors • They affect various cells -- lymphocytes , Eosinophils , neutrophils , macrophages , mast cells , egBeclomethasone , Budesonide , Fluticasone by dr swati prashant MD. drprashantw@gmail.com

35. Mast cell stabilisers : egCromolyn Sodium • They act by ↓ Ig E antibodies induced rlease of of inflammatory mediators rom mast cells . • Leukotriene modifiers : ↓ snthesis , antagonise the receptors .( monteleukast ) by dr swati prashant MD. drprashantw@gmail.com

36. Theophylline : phosphodiesterase inhibitor • Bronchodilation , antiinflammation • MDI , Dry powder inhaler Nebuliser. • In exercise induced asthma : use short acting before exercise & long acting in morning prevents asthma for 12—24 hrs . by dr swati prashant MD. drprashantw@gmail.com

37. THANK YOU • Our group websites for students • Pharmacology4students.com • Psm4students.com • Anatomy4students.com • Microbiology4students.com • Biochemistry4students.com • We invite faculties/studentsto write on topics of undergraduate levels. by dr swati prashant MD. drprashantw@gmail.com