Aliverti A, Dellacà R, Pelosi P, Chiumello D, Gatihnoni L, Pedoti A
Dipartimento di Bioingegneria, Politecnico di Milano, Italy.
Ann Biomed Eng. 2001 Jan;29(1):60-70. doi: 10.1114/1.1332084.
Optoelectronic plethysmography (OEP) has been shown to be a reliable method for the analysis of chest wall kinematics partitioned into pulmonary rib cage, abdominal rib cage, abdomen, and right and left side in the seated and erect positions. In this paper, we extended the applicability of this method to the supine and prone positions, typically adopted in critically ill patients. For this purpose we have first developed proper geometrical and mathematical models of the chest wall which are able to provide consistent and reliable estimations of total and compartmental volume variations in these positions suitable for clinical settings. Then we compared chest wall (CW) volume changes computed from OEP(deltaVCW) with lung volume changes measured with a water seal spirometer (SP) (deltaVSP) in 10 normal subjects during quiet (QB) and deep (DB) breathing on rigid and soft supports. We found that on a rigid support the average differences between deltaVSP and deltaVCW were -4.2% +/- 6.2%, -3.0% +/- 6.1%, -1.7% +/- 7.0%, and -4.5% +/- 9.8%, respectively, during supine/QB, supine/DB, prone/QB, and prone/DB. On the soft surface we obtained -0.1% +/- 6.0%, -1.8% +/- 7.8%, 18.0% +/- 11.7%, and 10.2% +/- 9.6%, respectively. On rigid support and QB, the abdominal compartment contributed most of the deltaVCW in the supine (63.1% +/- 11.4%) and prone (53.5% +/- 13.1%) positions. deltaVCW was equally distributed between right and left sides. In the prone position we found a different chest wall volume distribution between pulmonary and abdominal rib cage (22.1% +/- 8.6% and 24.4% +/- 6.8%, respectively) compared with the supine position (23.3% +/- 9.3% and 13.6% +/- 13.0%).
光电体积描记法（OEP）已被证明是一种可靠的方法，可用于分析在坐姿和直立姿势下划分为肺胸廓、腹胸廓、腹部以及左右两侧的胸壁运动学。在本文中，我们将该方法的适用性扩展到了危重病患者通常采用的仰卧位和俯卧位。为此，我们首先开发了合适的胸壁几何和数学模型，这些模型能够对适合临床环境的这些体位下的总体积和分区体积变化提供一致且可靠的估计。然后，我们比较了10名正常受试者在刚性和软支撑上安静呼吸（QB）和深呼吸（DB）期间，由OEP计算得出的胸壁（CW）体积变化（deltaVCW）与用水封式肺活量计（SP）测量的肺体积变化（deltaVSP）。我们发现，在刚性支撑上，仰卧位/QB、仰卧位/DB、俯卧位/QB和俯卧位/DB期间，deltaVSP与deltaVCW之间的平均差异分别为-4.2%±6.2%、-3.0%±6.1%、-1.7%±7.0%和-4.5%±9.8%。在软表面上，我们分别得到-0.1%±6.0%、-1.8%±7.8%、18.0%±11.7%和10.2%±9.6%。在刚性支撑和QB时，仰卧位（63.1%±11.4%）和俯卧位（53.5%±13.1%）时，腹部区域对deltaVCW的贡献最大。deltaVCW在左右两侧平均分布。在俯卧位时，我们发现肺胸廓和腹胸廓之间的胸壁体积分布与仰卧位（分别为23.3%±9.3%和13.6%±13.0%）不同（分别为22.1%±8.6%和24.4%±6.8%）。
