CIRCULAR INSTRUCTION REGARDING ESTABLISHMENT OF IMPAIRMENT DUE TO OCCUPATIONAL LUNG DISEASE FOR THE PURPOSES OF AWARDING PERMANENT DISABLEMENT

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1 Circular Instruction 195 CIRCULAR INSTRUCTION REGARDING ESTABLISHMENT OF IMPAIRMENT DUE TO OCCUPATIONAL LUNG DISEASE FOR THE PURPOSES OF AWARDING PERMANENT DISABLEMENT COMPENSATION FOR OCCUPATIONAL INJURIES AND DISEASES ACT, 1993 (COIDA) (NO. 130 of 1993) AS AMENDED. The following circular instruction is issued to clarify the position in regard to the establishment of impairment due to an occupational lung disease for the purposes of awarding permanent disablement and supersedes all previous instructions regarding compensation for occupational lung diseases EXCEPT for pneumoconiosis, lung cancer, mesothelioma and occupational/irritant induced asthma. 1. PURPOSE This instruction is issued to assist medical practitioners: in the selection of the appropriate investigative tool to confirm the diagnosis of an occupational lung disease in establishing impairment due to an occupational lung disease in assessing disablement from an occupational lung disease 2. DEFINITION Occupational lung diseases are a group of diseases characterized by structural and/or functional impairment of the lungs due to causes and conditions attributable to a particular working environment. Occupational lung diseases covered by this instruction include

2 pulmonary tuberculosis, chronic obstructive pulmonary disease (COPD), allergic alveolitis, byssinosis and any other occupational lung disease not covered by existing Circular Instructions. 3. CLINICAL ASSESSMENT Clinical assessment for establishing an occupational lung disease should be performed by a medical practitioner registered with the Health Professions Council of South Africa. The recommended steps in the clinical assessment of the employee are listed below. The evaluating/treating medical practitioner should: Obtain a full occupational history from the employee. Obtain a history from the patient concerning the nature of work-related exposures. In addition, the medical practitioner should inquire about any mitigating factors such as the use of respirators or exhaust ventilation. Where appropriate, work-related exposure information obtained from the patient should be supplemented by industrial hygiene reports or other exposure information. Inquire about non-occupational exposures (e.g. cigarette smoking, pets and hobbies). Obtain a careful medical history of current and previous pulmonary conditions including treatment. Particular attention should be paid to respiratory symptoms (e.g. cough, dyspnoea, wheeze, chest pain) Perform a careful physical examination. Choose appropriate laboratory testing and radiological investigations based upon the nature of exposures, the symptoms, and the physical examination. 4. DIAGNOSIS The diagnosis of an occupational lung disease should be made according to acceptable medical standards (at any given time) unless otherwise specified in the relevant Circular Instruction. The diagnosis should include at least the following information: Exposure to an agent known to cause, or with potential to cause, an occupational lung disease. A registered medical practitioner s diagnosis of the occupational lung disease accompanied by supporting documentation and test results, e.g. chest radiograph,

3 pulmonary function tests for COPD and sputum microscopy for pulmonary tuberculosis. An appropriate chronological relationship between work-related exposure and the development of an occupational lung disease. 5. GUIDELINES OR CODE OF PRACTICE FOR PULMONARY FUNCTIONS, RADIOLOGICAL AND LABORATORY INVESTIGATIONS TO CONFIRM THE DIAGNOSIS AND THE ESTABLISHMENT OF IMPAIRMENT. 5.1 Pulmonary function tests Pulmonary function tests must be carried out in accordance with the guidelines published by the South African Thoracic Society and other international organisations (e.g. American Thoracic Society) as amended from time to time (see Appendix 1). The name and identification details together with the age, height and sex of the patient must be indicated on the test printout. Physical records of all three spirometry attempts should be provided. Failure to provide the results as per stipulated format may jeopardise the expeditious resolution of the claim (see Appendix 1). With regard to the predicted values to be used in pulmonary function testing for compensation purposes, standards of the European Community for Coal and Steel (ECCS) without ethnic correction will be used as reference standards when determining impairment 1. These tests will be post-bronchodilator spirometric tests (FVC, FEV 1, FEV 1 /FVC ratio) in most cases. Where appropriate, gas diffusion tests and exercise testing may be necessary for full evaluation of certain conditions. Measured exercise testing such as the oxygen uptake during exercise (VO2max) and the 6 minute walk test should be reserved for those cases where the medical practitioner believes that the usual tests may have underestimated the impairment in a symptomatic patient. 2,5 5.2 Radiological Tests The chest radiographs must be full size (35cmx43cm) and of high technical quality since poor technique and processing of radiographs (e.g. under/over exposed, under-inspired, 1 Quanjer PhH, Tammeling GJ, Cotes OF, Pedersen OF, Peslin R, Yernault JC. Lung volumes and forced ventilatory flows. Report of Working party on standardisation of Lung Function tests, European Community for Steel and Coal. Official Statement of the European Society. European Respiratory Journal Suppl 1993; 16: American Medical Association. Guides to the Evaluation of Permanent Impairment. 5 th edition, 2000.

4 blurred outlines, artefacts) can lead to mis-diagnosis of pulmonary abnormalities. The name and identification details of the claimant together with the date of the chest radiograph must appear on the film. Failure to provide the radiographs as per stipulated format may jeopardise the expeditious resolution of the claim. Computer tomographic (CT) scans are not indicated for the evaluation of a claimant with a dust exposure history, normal lung function and the absence of symptoms. CT scans should be limited to those situations where a specific indication exists. Should such a situation arise a detailed motivation needs to be submitted to the medical officers of the Fund for approval. 5.3 Pathology results Pathology tests should be performed for certain pulmonary conditions where appropriate. These include sputum for microscopy, culture and sensitivity. The results must be reported by a pathologist and must include the date on which the specimen was obtained, the date of receipt of the specimen by the laboratory, the date of diagnosis and the name and identification details of the claimant. Certain immunological tests may be used for the diagnosis of immunologically-mediated occupational lung disease. 5.4 Post-mortem results The post-mortem report must include the name and identification details of the claimant, the date of death, the date of receipt of the specimen by the laboratory, and the date of diagnosis. 6. CRITERIA FOR ASSESSMENT OF IMPAIRMENT 6.1 Degree of Impairment: The degree of respiratory impairment should be assessed by evaluating structural and pulmonary function components: a) The structural components are assessed by means of chest radiography and CT scans in certain circumstances.

5 b) Pulmonary function is assessed using spirometry (e.g. FEV 1, FVC) and other specialised tests (e.g. diffusion tests, exercise testing) where appropriate. 6.2 The translation of impairment into percentage disablement In assessing pulmonary function impairment the approach of the American Medical Association (AMA) is followed giving rise to three classes of whole person impairment: mild, moderate and severe impairment. It is suggested that this takes place in 3 steps: Step 1. Determine the degree of structural impairment by reading the chest radiograph. Step 2. Determine the degree of pulmonary function impairment (normal, mild, moderate, severe) by using Table 1. If any of the three spirometric criteria from the cells in any one of the rows in Table 1 are met, then the classification of whole person impairment into mild, moderate or severe is given by that row (unless the DLCO or VO2 max places the person into a more severe impairment category than the spirometric values in which case the more severe category will pertain for use in Table 2). Step 3: Translate the combination of the degrees of structural and functional impairment to the degree of disability, using Table 2. If there is doubt or uncertainty at any point in this process, the claim may be referred to the appropriate Provincial Medical Advisory Panel (PMAP) or the medical officers of the Fund. Table 1. Translation of spirometric function to a severity of impairment classification (mild, moderate and severe) for the whole person following the American Thoracic Society (ATS) classification FVC % FEV 1 % FEV 1 / FVC *DLCO **VO2 Predicted Predicted ratio MAX Mild >20 Moderate Severe 50 or less 40 or less 40 or less 40 or less <15 * Single breath diffusing capacity of carbon monoxide which provides information on the efficiency of gas transfer across the alveoli ** Uptake of oxygen to measure exercise capacity

6 Table 2. Translation into Whole Person Impairment and Percentage Disablement (PD) Impairment Structural impairment only Functional impairment Impairment range based on AMA Whole Body Impairment and ATS classification of work capacity Evidence of radiological features, no pulmonary function changes of occupational lung disease with or without symptoms AMA PD (maximal impairme nt) <10% 20% - Mild AMA 3 Class 2: 10-25% impairment of the whole person ATS 4 : Can still do most jobs 25% 40% - Moderate AMA Class 3: 26-50% impairment of the whole person ATS: Increasingly cannot meet the demands of many jobs 50% 70% - Severe AMA Class 4: % impairment of the whole person ATS: Cannot do any job 100% 100% Note: Table 1 provides an assessment of lung function impairment only and is therefore inadequate for the assessment of permanent disability. The AMA guide (maximal value of the proposed range) translates impairment into permanent disablement (PD) by taking into account subjective symptoms suffered, use of medication, impact on quality of life and impaired occupational functioning of the claimant. 7. BENEFITS 7.1 Temporary disablement Payment for temporary total disablement shall be made for as long as such disablement occurs, but not for a period exceeding 24 months 7.2 Permanent disablement 3 American Medical Association (AMA) 4 American Thoracic Society (ATS)

7 Payment for permanent disablement shall be made where applicable, and when a final medical report is received and no further improvement in clinical, structural or functional impairment is envisaged. This will be based according to the criteria contained in Table 2. In the case of Pulmonary Tuberculosis permanent disablement will be assessed on the basis of lung function tests performed 12 months after the completion of medical therapy as per Circular Instruction Medical Aid Medical aid shall be provided for a period of not more than 24 months from the date of diagnosis or longer, if in the opinion of the Director-General, further medical aid will reduce the extent of the disablement. Medical aid covers costs of diagnosis and any necessary treatment provided by any health care provider. The compensation Commissioner shall decide on the need for, the nature and sufficiency of medical aid supplied. 7.4 Death benefits Reasonable burial expenses, widow s and dependent s pensions may be payable, where applicable, if the employee dies as a result of the occupational lung disease. 8. REPORTING The following documentation should be submitted to the Compensation Commissioner or the employer individually liable or the mutual association concerned: Employer s report of an Occupational Disease (W.CL.1) First Medical Report in respect of an Occupational Disease (W.CL.22) Notice of an Occupational Disease and Claim for Compensation (W.CL.14) Exposure History (W.CL.110) or an appropriate employment history Progress Medical report in respect of an Occupational Disease (W.CL26) Medical Report detailing the claimant s symptoms, clinical features and medication required is essential

8 Relevant laboratory results in support of diagnosis e.g. sputum microscopy, culture and sensitivity for pulmonary tuberculosis. Chest radiograph and/or radiology reports where applicable Pulmonary function tests performed in accordance with the South African Thoracic Society guidelines (see Appendix 1) Final Medical Report in respect of an Occupational Disease (W.CL26) when the claimant s condition has reached maximum medical improvement. The most recent lung function tests available, which include pre-and post administration of a bronchodilator where appropriate, and medication prescribed should be attached to the report 9. CLAIMS PROCESSING The office of the Compensation Commissioner shall consider and adjudicate upon the liability of all claims. The Medical officers in the Compensation Commissioner s Office are responsible for medical assessment of a claim and for the confirmation of the acceptance or rejection of a claim. DIRECTOR-GENERAL: LABOUR

9 APPENDIX 1 ACCEPTABILITY AND REPRODUCIBILITY CRITERIA FOR PULMONARY FUNCTION TESTING 5 Individual spirograms will be classified as acceptable if they have: A crisp, unhesitating start; Peak expiratory flow rate (PEFR) of the flow-volume curve is achieved within the first 25% of the volume expired from maximal inspiration (Most individuals are able to produce PEFR within the first 15% of the volume expired); A continuous smooth exhalation without artifacts caused by coughing, variable effort, second inhalations or leaks influencing FEV 1 or FVC; A complete exhalation (to the point where no more air can be expelled from the lungs), until the volume-time curve has clearly reached a plateau or the flow- volume curve has progressively returned to zero flow. This should be at least 6 seconds. Spirograms will be considered reproducible if: Evidence is provided of three technically acceptable curves; Two acceptable curves in which the FEV 1 and FVC of the different curves do not differ by greater than 200 ml from each other; No more than 8 curves trials should have been performed during a single session because fatigue induced by repeated FVC trials may lead to inaccurate results. The best measure of FEV 1 and FVC from any of the 3 acceptable curves will be used to calculate the FEV 1 /FVC ratio for assigning an impairment rating. In cases of spirometry failure (patient unable to produce acceptable/reproducible curves), clear reasons must be stated for this including whether severe clinical disease is present. 5 Adapted from South African Thoracic Society Standards of Spirometry Committee: EM van Schalkwyk, C Schultz, JR Joubert, NW White. Guideline for Office Spirometry in Adults, South African Medical Journal. 2004; 94(7):