Lin Ming-I, Groves William A, Freivalds Andris, Lee Eun Gyung, Harper Martin, Slaven James E, Lee Larry
The Pennsylvania State University, University Park, PA 16802-5000, USA.
J Environ Monit. 2008 Oct;10(10):1179-86. doi: 10.1039/b806292g.
A study was conducted to evaluate a portable respiratory inductive plethysmograph (RIP) as a means to estimate minute ventilation (V(E)) for use in controlling the flow rate of a physiologic sampling pump (PSP). Specific aims were to: (1) evaluate the ability of the portable RIP system to measure V(E) using a direct (individual) fixed-volume calibration method (Direct RIP model), (2) develop and evaluate the performance of indirect (group) regression models for V(E) prediction using output data from the portable RIP and subject demographic characteristics (Indirect RIP model), and (3) compare V(E) estimates from indirect and direct portable RIP calibration with indirect estimation models published previously. Nine subjects (19-44 years) were divided into calibration (n = 6) and test (n = 3) datasets and performed step-tests on three different days while wearing the portable RIP and breathing through a pneumotachometer (reference). Minute ventilation and portable RIP output including heart rate, breathing rate, and a motion index were recorded simultaneously during the 80 minute sessions. Calibration data were used to develop a regression model for V(E) prediction that was subsequently applied to the test dataset. Direct calibration of the portable RIP system produced highly variable estimates of V(E) (R2 = 0.62, average % error = 15 +/- 50) while Indirect RIP model results were highly correlated with the reference (R2 = 0.80-0.88) and estimates of total volume were within 10% of reference values on average. Although developed from a limited dataset, the Indirect RIP model provided an alternative approach to estimation of V(E) and total volume with accuracy comparable to previously published models.
开展了一项研究，以评估便携式呼吸感应体积描记器（RIP）作为估计分钟通气量（V(E)）的一种手段，用于控制生理采样泵（PSP）的流速。具体目标如下：（1）使用直接（个体）固定体积校准方法（直接RIP模型）评估便携式RIP系统测量V(E)的能力；（2）利用便携式RIP的输出数据和受试者人口统计学特征，开发并评估用于V(E)预测的间接（群体）回归模型（间接RIP模型）；（3）将间接和直接便携式RIP校准得到的V(E)估计值与先前发表的间接估计模型进行比较。9名受试者（19 - 44岁）被分为校准数据集（n = 6）和测试数据集（n = 3），并在三天内佩戴便携式RIP并通过呼吸速度计（参考设备）进行呼吸时完成了阶梯测试。在80分钟的测试过程中，同时记录分钟通气量和便携式RIP的输出，包括心率、呼吸频率和运动指数。校准数据用于开发V(E)预测的回归模型，随后应用于测试数据集。便携式RIP系统的直接校准产生的V(E)估计值变化很大（R2 = 0.62，平均误差百分比 = 15 +/- 50），而间接RIP模型结果与参考值高度相关（R2 = 0.80 - 0.88），总体积估计值平均在参考值的10%以内。尽管间接RIP模型是从有限的数据集中开发出来的，但它提供了一种估计V(E)和总体积的替代方法，其准确性与先前发表的模型相当。
