Figures
- Figure 1–
The place of specific inhalation challenge (SIC) in the diagnosis of occupational asthma. In some centres it is the first-choice technique, in others it is used selectively in the context of other diagnostic approaches (white boxes). PEF: peak expiratory flow; FEV1: forced expiratory volume in 1 s; NSBHR: nonspecific bronchial hyperresponsiveness.
- Figure 2–
Schematic flowchart for performing specific inhalation challenge with an occupational agent. The timing of some measurements varies between centres. FEV1: forced expiratory volume in 1 s; NSBHR: nonspecific bronchial hyperresponsiveness; FeNO: exhaled nitric oxide fraction. #: proceed to additional active challenge(s) when the changes in FEV1 on day 2 are equivocal or negative and challenge with a higher dose is considered appropriate, or when there is a significant increase in sputum eosinophils or in FeNO post-day 2 challenge. ¶: NSBHR can be measured in the morning before the control and active challenge exposures provided that no inhaled bronchodilator is administered.
Tables
- Table 1– Key messages for performing and interpreting specific inhalation challenge (SIC) with occupational agents
General safety requirements, contraindications and precautions should be strictly applied in order to minimise the risk of severe adverse events The duration or concentration of exposure to occupational agents should only be gradually increased under close monitoring of functional parameters A control challenge test with a 6–8 h period of spirometric monitoring on a separate day is required for the interpretation of the SIC results Changes in FEV1 should be the primary physiological outcome measure, but other functional indices (i.e. airway resistance/conductance) may be useful in subjects who are not able to complete reproducible expiratory manoeuvres NSBHR should be measured at least before the SIC and at the end of a negative SIC procedure. A significant increase in post-challenge NSBHR provides further evidence for a positive response when changes in FEV1 are indeterminate and indicates that additional challenges are necessary before excluding a diagnosis of occupational asthma Sputum eosinophils and FeNO may help interpret equivocal tests and indicate the need for longer SIC exposures to reduce the risk of false-negative results FEV1: forced expiratory volume in 1 s; NSBHR: nonspecific bronchial hyperresponsiveness; FeNO: exhaled nitric oxide fraction.
Supplementary material
Please note: supplementary material is not edited by the Editorial Office, and is uploaded as it has been supplied by the author.
Files in this Data Supplement:
- Appendix A - Bibliographic search strategy
- Appendix B - Workplace challenges
- Final handbook - HANDBOOK OF PROCEDURES FOR SPECIFIC INHALATION CHALLENGE TESTING IN THE DIAGNOSIS OF OCCUPATIONAL ASTHMA
Disclosures
Files in this Data Supplement:
Jump To
- Article
- Abstract
- Abstract
- Introduction
- Task Force methodology
- Rationale and indications for performing specific inhalation challenges
- Methodology of specific inhalation challenges
- Assessment of bronchial response
- Interpretation of specific inhalation challenge results
- Limitations of specific inhalation challenges
- Research needs
- Conclusion
- Footnotes
- References
- Figures & Data
- Info & Metrics