This document discusses occupational asthma, including its diagnosis and management. It defines occupational asthma as asthma caused by workplace exposures, characterized by asthma symptoms that improve away from work and worsen upon return. Diagnosis involves assessing exposure history and documenting the relationship between symptoms and work. Spirometry can show reduced lung function and improvement post-bronchodilator. Peak flow monitoring may also be used. Treatment is similar to asthma treatment and involves controllers like inhaled corticosteroids and relievers like bronchodilators. Avoiding causal exposures is also important.

1. • DIAGNOSIS
• MONITORING
ASSESSMENT OF
OCCUPATIONAL ASTHMA

2.  History of exposure to sensitizing agents
 Absence of asthma symptoms before beginning
employment
 Documented relationship between symptoms and
workplace (improving symptom when away from work
& worsening symptoms upon return to work
HISTORY

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WHAT SYMPTOMS SHOULD YOU LOOK
OUT FOR?
 The symptoms start as
 runny eyes and nose
 itchy eyes and nose
 and may develop into the more serious problems of
asthma
 breathlessness
 wheezing
 tightness of chest
 coughing

4. DIAGNOSING OCCUPATIONAL ASTHMA
History
Investigation
Detailed history of past & present
occupational exposures
Cough – at work/ end of shift,
precedes wheezing
Concurrent – rhinorrhoea,
nasal congestion,
lacrimation, conjunctivitis
Symptoms improve – at weekends &
holidays, persist – advanced stage.

5. Diagram – Spirometry
Parameters
Procedure
Diagnosis
SPIROMETRY

9.  FEV1 (Forced expiratory volume in 1 second)
 Forced Vital Capacity (FVC)
 FEV1/FVC ratio
PARAMETERS

10. Marked reduced in FEV1
Reduced in FVC
The FEV1/ FVC ratio is reduced
Significant improvement of the FEV 1 (>12%)
following administration of a bronchodilator
Diurnal variability
DIAGNOSIS

11. Measure expiration
Easy
Steps
PEAK EXPIRATORY FLOW METER

12. STEPS TO USE PEAK EXPIRATORY FLOW
METER
1. Stand up or sit up straight.
2. Make sure the indicator is at the bottom of the meter
(zero).
3. Take a deep breath in, filling the lungs completely.
4. Place the mouthpiece in your mouth; lightly bite with your
teeth and close your lips on it. Be sure your tongue is away
from the mouthpiece.
5. Blast the air out as hard and as fast as possible in a single
blow.
6. Remove the meter from your mouth.
7. Record the number that appears on the meter and then
repeat steps one through seven two times.
8. Record the highest of the three readings in an asthma
diary. This reading is your peak expiratory flow (PEF).

13. Similar with asthma
Differs according to the severity :
1. PEF > 75% of predicted or best value (MILD)
2. PEF between 50% – 75% of predicted or best
value (MODERATE)
3. PEF < 50% of predicted or best value
(SEVERE)
4. PEF < 30% of predicted or best value
 Reversibility testing
DIAGNOSIS

14. Pharmacological therapy for OA is
identical to therapy for other
forms of asthma, but it is not
substitute for adequate avoidance
PHARMACOLOGICAL THERAPY
(Bateman, et al, 2008)

15. PHARMACOLOGICAL THERAPY
Treatment
Controllers Relievers
1) Inhaled glucocorticosteroids 1) Rapid-acting inhaled b2-agonists
2) Leukotriene modifiers 2) Anticholinergics
3) Long-acting inhaled b2-agonists 3) Short-acting oral b2-agonists
4) Theophylline
5) Anti-IgE
6) Others
Systemic glucocorticosteroids
Oral anti-allergic compounds

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OCCUPATIONAL ASTHMA CHECKLIST
Reminder, if you have trouble with
wheezing, coughing or shortness of breath
at work, you could have occupational
asthma:
 Consult your physician. He or she may suggest a lung function test.
 See your work supervisor for details about potential hazards in your work
environment.
 Have the tests and evaluation required to prove the suspected
occupational asthma and its cause.
 Seek your physician's advice about therapy for occupational asthma.

17.  Pre employment stage: asked about pre existing
asthma (not suitable for this work)
 Lung function test and referral for immunological
blood test or skin prick test may be appropriate
 Frequent health surveillance indicated
 First few years of exposure (OA risk greatest during early years)
 Workers with pre existing asthma
 Workers who develop rhinitis & workplace exposure should be
investigated and reduced
HEALTH SURVEILLANCE