Department of Chest Medicine, Sacré-Coeur Hospital, Montreal, Canada.
Respir Res. 2010 Jun 9;11(1):72. doi: 10.1186/1465-9921-11-72.
Inhalation challenges are used for diagnosing occupational asthma (OA). The initial methodology consisted of a "realistic" exposure without monitoring nor controlling exposure. Our aim was to design an equipment, called the GenaSIC, that allows the generation of various agents regardless of the formulation and to assess the feasibility of its use in patients investigated for OA.
GenaSIC can generate lactose, flour, malt, isocyanates, formaldehyde and N-butyl acetate with precise and fairly stable concentrations. Using N-butyl-acetate as a control agent and real time measurement, we show that normal breathing has a negligible effect on the concentration. We exposed forty-four different subjects to a control agent and/or to a suspected occupational agent. Nineteen of the subjects were only exposed to N-butyl acetate as a control agent without experiencing any significant irritant effect (no significant changes in spirometry thereafter). Eight subjects who were exposed to both N-butyl acetate and formaldehyde did not show significant reactions. Seven subjects were exposed to dry particles (flour in six instances, malt in the other) and five showed immediate asthmatic reactions which changes in FEV1 from 20% to a maximum of 28%. Finally, ten subjects were exposed to isocyanates, four of whom showed a positive reaction, including one subject with immediate maximum changes in FEV1 of 22%.
GenaSIC offers the possibility of reliable and safe exposures to dry particles, formaldehyde and isocyanates in the investigation of OA.
吸入挑战被用于诊断职业性哮喘（OA）。最初的方法学是在没有监测和控制暴露的情况下进行“现实”暴露。我们的目的是设计一种称为 GenaSIC 的设备，该设备可以生成各种制剂的各种制剂，并且评估其在 OA 患者中使用的可行性。
GenaSIC 可以精确且相对稳定地生成乳糖、面粉、麦芽、异氰酸酯、甲醛和正丁酯。使用正丁酯作为对照剂并进行实时测量，我们表明正常呼吸对浓度的影响可以忽略不计。我们将 44 名不同的受试者暴露于对照剂和/或可疑职业性制剂。19 名受试者仅暴露于正丁酯作为对照剂，没有出现任何明显的刺激性作用（此后肺活量计检查没有明显变化）。暴露于正丁酯和甲醛的 8 名受试者没有表现出明显的反应。暴露于干颗粒（面粉 6 例，麦芽 1 例）的 7 名受试者出现了立即的哮喘反应，FEV1 从 20%最大变化到 28%。最后，10 名受试者暴露于异氰酸酯，其中 4 名出现阳性反应，包括一名受试者的 FEV1 最大立即变化为 22%。
GenaSIC 为 OA 调查中可靠和安全地暴露于干颗粒、甲醛和异氰酸酯提供了可能。
