Köhler D
Fachkrankenhaus Kloster Grafschaft.
Pneumologie. 1991 Aug;45 Suppl 2:659-69.
The unspecific bronchial provocation test--usually performed with histamine, metacholine or carbachol--is used to determine whether bronchial hyperreactivity is present, and to what degree. Epidemiological studies have shown, that an overlap exists between "healthy" and "sick". There are several reasons for this, the most important being the insufficient reproducibility of intrabronchial deposition and the fact that the total provocation dose is often unknown. The following factors must be taken into account to improve this situation: 1. Only those devices where the particle spectrum is not influenced by the inspiration flow (without additional airstream) should be used to produce aerosols. 2. The air current containing aerosols is vapour saturated when liquid aerosols are produced. As the vapour is derived from the nebulizing solution it forms part of the weight or volume loss, this can be up to 50% of the total weight/volume loss. The aerosol output is far more constant and practically independent of the vapour saturation and the temperature. The intrabronchial dose can therefore not be calculated according to the weight loss of the nebulizer, as this is incorrect. 3. The evaporation of the nebulizing solution leads to an increase in the concentration of the test substance, especially towards the end of the evaporation process. Thus, the volume of the nebulizing solution should always be as large as possible or renewed early. 4. The slower the inhalation maneuver, the less the reproducibility of the intrabronchial deposition is impaired. The intrabronchial deposition varies least, when a slow inspiratory vital capacity maneuver is carried out (inspiration time greater than 8 s). Exhalation should be normal or even rapid, as aerosol deposition is thus increased, due to airway collapse. Breath-holding at the end of inspiration, for about 3-4 seconds, is favourable. 5. The anatomy of the glottic region varies greatly interindividually, influencing intrabronchial deposition. To reduce this to a minimum, the average diameter of the particles should not exceed 2 microns. On the other hand, the diameter of particles should not be under 1 micron, as the inhaled amount of substance is then markedly reduced (volume approximately d3). 6. Reservoirs, storaging the aerosol before inhalation, increase reproducibility, since they stabilize the aerosol due to vapour saturation. Plastic reservoirs must either be of antistatic material, or made antistatic by being filled repeatedly. The reproducibility of intrabronchial deposition is in the range of +/- 15% for the PARI-Provokationstest device I, (determined by radioactive labelling).(ABSTRACT TRUNCATED AT 400 WORDS)
非特异性支气管激发试验——通常使用组胺、乙酰甲胆碱或卡巴胆碱进行——用于确定是否存在支气管高反应性以及其程度如何。流行病学研究表明，“健康”与“患病”之间存在重叠。造成这种情况有几个原因，最重要的是支气管内沉积的再现性不足以及总激发剂量往往未知。为改善这种情况，必须考虑以下因素：1. 仅应使用那些颗粒谱不受吸气气流影响（无额外气流）的装置来产生气溶胶。2. 当产生液体气溶胶时，含有气溶胶的气流应饱和水蒸气。由于水蒸气源自雾化溶液，它构成重量或体积损失的一部分，这可能高达总重量/体积损失的50%。气溶胶输出更为恒定，实际上与水蒸气饱和度和温度无关。因此，不能根据雾化器的重量损失来计算支气管内剂量，因为这是不正确的。3. 雾化溶液的蒸发会导致测试物质浓度增加，尤其是在蒸发过程接近尾声时。因此，雾化溶液的体积应始终尽可能大或尽早更换。4. 吸入动作越慢，支气管内沉积的再现性受影响越小。当进行缓慢的吸气肺活量动作（吸气时间大于8秒）时，支气管内沉积变化最小。呼气应正常甚至快速，因为由于气道塌陷，这样会增加气溶胶沉积。吸气结束时屏气约3 - 4秒是有利的。5. 声门区域的解剖结构个体间差异很大，会影响支气管内沉积。为将此降至最低，颗粒的平均直径不应超过2微米。另一方面，颗粒直径不应低于1微米，因为此时吸入的物质量会显著减少（体积约为d3）。6. 在吸入前储存气溶胶的容器可提高再现性，因为它们通过水蒸气饱和使气溶胶稳定。塑料容器要么必须由抗静电材料制成，要么通过反复填充使其具有抗静电性能。对于PARI - Provokationstest装置I，支气管内沉积的再现性在±15%范围内（通过放射性标记确定）。
