Petrini M F, Dwyer T M, Phillips M S
J Appl Physiol Respir Environ Exerc Physiol. 1983 Jul;55(1 Pt 1):258-62. doi: 10.1152/jappl.1983.55.1.258.
We developed a computerized method to measure pulmonary tissue volume (Vt) and capillary blood flow (Qc) that requires only a single interface for measurement of a soluble and an insoluble gas. The method uses a timing algorithm that replaces either a marker gas (C18O) or a volume signal. Gas concentrations are stored in digitized form. The data analysis consists of three parts: 1) initial and end-tidal samples found by using minima and maxima; 2) a timing algorithm derived from the end-tidal dead space method (ETDS, J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 44: 782-795, 1978); and 3) calculations of Vt and Qc, also by the ETDS method. Both the timing and Vt and Qc agree well with the hand-calculated values, but the coefficient of variation of Vt is slightly improved (6 vs. 7% manually). We conclude that our computerized method is equivalent to the manual ETDS method, but it is faster and more accurate; in addition, it has the advantage of requiring only one interface without the use of expensive gases.
我们开发了一种计算机化方法来测量肺组织容积（Vt）和毛细血管血流量（Qc），该方法仅需一个界面即可测量一种可溶气体和一种不溶气体。该方法使用一种计时算法，该算法可替代标记气体（C18O）或容积信号。气体浓度以数字化形式存储。数据分析包括三个部分：1）通过使用最小值和最大值找到的初始和终末潮气样本；2）源自终末潮气死腔法（ETDS，《应用生理学杂志：呼吸、环境与运动生理学》44：782 - 795，1978）的计时算法；3）同样通过ETDS方法计算Vt和Qc。计时以及Vt和Qc与手工计算值都非常吻合，但Vt的变异系数略有改善（分别为6%和手工计算的7%）。我们得出结论，我们的计算机化方法等同于手工ETDS方法，但它更快且更准确；此外，它具有仅需一个界面且无需使用昂贵气体的优点。
