Wilson J R, Raven P B, Morgan W P, Zinkgraf S A, Garmon R G, Jackson A W
Department of Physiology, Texas College of Osteopathic Medicine, Fort Worth 76107.
Am Ind Hyg Assoc J. 1989 Feb;50(2):85-94. doi: 10.1080/15298668991374345.
Current regulations governing the certification of respiratory protective devices are based on data published in the early 1950s. The limited data base of this early work and documented increases in the average height of the population underscore the need for additional information concerning the parameters of certification. In the present study, a protocol using an inclined treadmill (0.5% grade every 12 sec) was used to test a heterogeneous population (n = 38). Through submaximal up to and including maximal exercise levels with and without respirator wear, maximal oxygen uptake (VO2max) was significantly greater (p less than 0.01) with the respirator (44.11 +/- 1.3 mL/kg.min) than without the respirator (42.18 +/- 1.4 mL/kg.min) while maximal ventilation volumes (VEmax) were not significantly different (with = 118.7 +/- 4 L/min; without 119.6 +/- 5 L/min). While peak inspired flows (PFI) with the respirator (268 +/- 7 L/min) were less than without the respirator (281 +/- 9 L/min), p greater than 0.05, the lower peak expired flow (PFE) with the respirator (289 +/- 12 L/min) than without the respirator (324 +/- 13 L/min), p less than 0.01, indicated a significant blunting effect of the respiratory flows by the expired resistance during exercise to maximal levels. Peak inspired pressures (PPi) with and without the respirator were not significantly different (p greater than 0.05). The negative values obtained within the facepiece of the respirator (-7.65 +/- 0.8 cmH2O), however, indicate that the positive pressure within the facepiece was lost, and respiratory protection may be compromised. Peak expired pressure with the respirator (13.05 +/- 0.7 cmH2O) was significantly greater than without the respirator (10.7 +/- 0.5 cmH2O) indicating that, despite a lower PFE, greater force was required to overcome the resistances of the respirator on expiration. The dyspnea index, an index of physiological effort; suggests that the subjects were working at a higher percentage of their respiratory reserve with the respirator (p less than 0.05) than without. Perceptually, subjects also felt that breathing with the respirator was more difficult (p less than 0.05). The maximum heart rate and the ratings of perceived exertion were not significantly different between the two tests at maximal exercise levels. Maximum oxygen uptake was considered reached when subjects attained a respiratory exchange ratio of at least 1.15, when a heart rate response at or greater than age-predicted maximum was achieved, when ratings of perceived exertion indicated exhaustion, and/or when the measure of VO2 had plateaued during the final minute of exercise.(ABSTRACT TRUNCATED AT 400 WORDS)
当前关于呼吸防护设备认证的法规是基于20世纪50年代初公布的数据制定的。这项早期工作的数据库有限，而且有记录表明人口平均身高有所增加，这凸显了获取更多关于认证参数信息的必要性。在本研究中，使用了一种倾斜跑步机方案（每12秒坡度增加0.5%）来测试一组异质人群（n = 38）。在佩戴和不佩戴呼吸器的情况下，通过次最大运动直至包括最大运动水平，佩戴呼吸器时的最大摄氧量（VO2max）显著更高（p < 0.01）（44.11 ± 1.3 mL/kg·min），而不佩戴呼吸器时为（42.18 ± 1.4 mL/kg·min），同时最大通气量（VEmax）没有显著差异（佩戴时 = 118.7 ± 4 L/min；不佩戴时 = 119.6 ± 5 L/min）。虽然佩戴呼吸器时的吸气峰值流量（PFI）（268 ± 7 L/min）低于不佩戴呼吸器时（281 ± 9 L/min），p > 0.05，但佩戴呼吸器时的呼气峰值流量（PFE）（289 ± 12 L/min）低于不佩戴呼吸器时（324 ± 13 L/min），p < 0.01，这表明在运动至最大水平时，呼气阻力对呼吸流量有显著的削弱作用。佩戴和不佩戴呼吸器时的吸气峰值压力（PPi）没有显著差异（p > 0.05）。然而，在呼吸器面罩内获得的负值（-7.65 ± 0.8 cmH2O）表明面罩内的正压丧失，呼吸保护可能会受到影响。佩戴呼吸器时的呼气峰值压力（13.05 ± 0.7 cmH2O）显著高于不佩戴呼吸器时（10.7 ± 0.5 cmH2O），这表明尽管PFE较低，但呼气时需要更大的力量来克服呼吸器的阻力。呼吸困难指数是生理努力程度的指标；表明与不佩戴呼吸器相比，受试者佩戴呼吸器时在其呼吸储备的更高百分比下工作（p < 0.05）。从感知上来说，受试者也感觉佩戴呼吸器呼吸更困难（p < 0.05）。在最大运动水平下，两次测试之间的最大心率和主观用力程度评分没有显著差异。当受试者达到至少1.15的呼吸交换率、实现等于或大于年龄预测最大值的心率反应、主观用力程度评分表明疲劳和/或在运动的最后一分钟VO2测量值达到平稳时，认为达到了最大摄氧量。（摘要截断于400字）
