Work-Related Asthma is leading cause absenteeism among workforce

1. Work-Related Asthma Dr. Nayak CS, Consultant Occupational Medicine MB BS MD DOH FIIRSM MAOEM

6. Types of Work-related Asthma

7. Types of Work-related Asthma

16. Reactive airways dysfunction syndrome (RADS) 1. Single or several exposures to gas, smoke, fume or vapor which was present in very high concentrations and was irritant in nature. 2. Dyspnea, cough, asthmatic symptoms occurring usually within 24 hours after the exposure. 3. No latency time before symptoms. 4. Obstruction in spirometric values or in PEF follow-up or unspecific bronchial hyperreactivity in histamine or metacholine challenge test. 5. Possible earlier obstructive lung diseases clearly distinguished from the accidental incident. 6. Symptoms and functional findings last several months or remain permanent Piirilä et al. Ärsytyksen aiheuttama astma. Duodecim 2002;118

18. Occupational Asthma

19. Asthma Pathophysiology

20. Triggers and Irritants Things that may initiate an asthma attack

21. Exposure to nickel dust

22. Acute, high RADS Chronic, low  high Chronic bronchitis Asthma Asthma-like syndrome Sensitizer Atopic asthma Irritant Modified from do Pico 2004 Workplace exposure

23. Airway Remodeling Symptoms Smooth Muscle Dysfunction Airway Inflammation Asthma Pathophysiology

24. INFLAMMATION Pathogenesis: Airflow Limitation SYMPTOMS Cough Wheeze Dyspnoea TRIGGERS Allergens, Exercise, Cold Air, SO2 Particulates Airway Hyperresponsiveness INDUCERS Allergens, Chemical sensitizers, Air pollutants,

25. The bronchial epithelium is highlighted as a key site for

26. Leukotrienes C4, D4 & E4 Asthma Pathology - Modern view

27. Diagnostic Approach

28. Diagnostic Criteria

34. Exposure chamber

38. Serial monitoring of PEF in the diagnosis of OA Improvement of PEF when away from work and deterioration of PEF on returning to work

46. Compatible clinical history and exposure Skin testing and/or specific IgE (if possible) Assessment of NSBH Normal Increased Subject still at work Subject no longer at work Subject still at work Laboratory challenge tests Positive Negative Consider return to work Workplace challenge tests PEF monitoring, or both Positive Negative No asthma Occupational asthma Non occcupational asthma Use of other means (induced sputum, exhaled NO ) Chan Yeung M, Malo JL. NEJM 1995; 333:107 Algorithm for investigation of occupational asthma

47. Management

49. Management

50. 1.Pre-placement Assessment 2. Exposure control 3. PPE & Awareness MSDS Medical Surveillance 1.Employee Accommodations 2. Job Retraining 3. upgrading standards of care 3. upgrading accessibility of care primary prevention Tertiary prevention Secondary prevention Prevention & Control 1. map the magnitude of OA 2. analyse OA determinants 3. monitor future trends

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