Miodownik S, Carlon V A, Ferri E, Burda B, Melendez J A
Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
J Appl Physiol (1985). 2000 Jul;89(1):373-8. doi: 10.1152/jappl.2000.89.1.373.
Conventional gas-exchange instruments are confined to the measurement of O(2) consumption (VO(2)) and CO(2) production (VCO(2)) and are subject to a variety of errors. This handicaps the performance of these devices at inspired O(2) fraction (FI(O(2))) > 0.40 and limits their applicability to indirect calorimetry only. We describe a device based on the automation of the Douglas bag technique that is capable of making continuous gas-exchange measurements of multiple species over a broad range of experimental conditions. This system is validated by using a quantitative methanol-burning lung model modified to provide reproducible (13)CO(2) production. The average error for VO(2) and VCO(2) over the FI(O(2)) range of 0.21-0.8. is 2.4 and 0.8%, respectively. The instrument is capable of determining the differential atom% volume of known references of (13)CO(2) to within 3.4%. This device reduces the sources of error that thwart other instruments at FI(O(2)) > 0. 40 and demonstrates the capacity to explore other expressions of metabolic activity in exhaled gases related to the excretion of (13)CO(2).
传统的气体交换仪器仅限于测量氧气消耗（VO₂）和二氧化碳产生（VCO₂），并且存在各种误差。这限制了这些设备在吸入氧分数（FI(O₂)）> 0.40时的性能，并且仅将其应用局限于间接量热法。我们描述了一种基于道格拉斯袋技术自动化的设备，该设备能够在广泛的实验条件下对多种物质进行连续的气体交换测量。该系统通过使用经过改进以提供可重复的¹³CO₂产生的定量甲醇燃烧肺模型进行了验证。在FI(O₂)范围为0.21 - 0.8时，VO₂和VCO₂的平均误差分别为2.4%和0.8%。该仪器能够将已知¹³CO₂参考物的微分原子体积百分比测定到3.4%以内。该设备减少了在FI(O₂)> 0.40时阻碍其他仪器的误差来源，并展示了探索呼出气体中与¹³CO₂排泄相关的其他代谢活动表达方式的能力。
