Alvarez Francisco J, Gastiasoro Elena, Rey-Santano M Carmen, Gomez-Solaetxe Miguel A, Publicover Nelson G, Larrabe Juan L
Research Unit in Experimental Pulmonary Physiology, Hospital of Cruces, Basque Country Health's Service, Bilbao 48903, Spain.
IEEE Trans Biomed Eng. 2009 Jul;56(7):1938-48. doi: 10.1109/TBME.2009.2017275. Epub 2009 Mar 27.
Our aim was to develop a computerized system for real-time monitoring of lung mechanics measurements during both gas and liquid ventilation. System accuracy was demonstrated by calculating regression and percent error of the following parameters compared to standard device: airway pressure difference (Delta P(aw)), respiratory frequency (f(R) ), tidal volume (V(T)), minute ventilation (V'(E)), inspiratory and expiratory maximum flows (V'(ins,max), V'(exp,max)), dynamic lung compliance (C(L,dyn) ), resistance of the respiratory system calculated by method of Mead-Whittenberger (R(rs,MW)) and by equivalence to electrical circuits (R(rs,ele)), work of breathing (W(OB)), and overdistension. Outcome measures were evaluated as function of gas exchange, cardiovascular parameters, and lung mechanics including mean airway pressure (mP(aw)). Delata P(aw), V(T), V'(ins,max), V'(exp,max), and V'(E) measurements had correlation coefficients r = 1.00, and %error < 0.5%. f(R), C(L,dyn), R(rs,MW), R(rs,ele), and W(OB) showed r > or = 0.98 and %error < 5%. Overdistension had r = 0.87 and %error < 15%. Also, resistance was accurately calculated by a new algorithm. The system was tested in rats in which lung lavage was used to induce acute respiratory failure. After lavage, both gas- and liquid-ventilated groups had increased mP(aw) and W(OB), with decreased V(T), V'(E), C(L,dyn), R(rs,MW), and R(rs,ele) compared to controls. After 1-h ventilation, both injured group had decreased V(T), V'(E) , and C(L,dyn), with increased mP(aw), R(rs,MW), R(rs,ele), and W(OB) . In lung-injured animals, liquid ventilation restored gas exchange, and cardiovascular and lung functions. Our lung mechanics system was able to closely monitor pulmonary function, including during transitions between gas and liquid phases.
我们的目标是开发一种计算机系统，用于在气体通气和液体通气期间实时监测肺力学测量值。通过计算与标准设备相比以下参数的回归值和百分比误差，证明了系统的准确性：气道压差（ΔP(aw)）、呼吸频率（f(R)）、潮气量（V(T)）、分钟通气量（V'(E)）、吸气和呼气最大流量（V'(ins,max)、V'(exp,max)）、动态肺顺应性（C(L,dyn)）、用米德 - 惠滕伯格方法计算的呼吸系统阻力（R(rs,MW)）以及等效电路法计算的呼吸系统阻力（R(rs,ele)）、呼吸功（W(OB)）和过度扩张。作为气体交换、心血管参数以及包括平均气道压（mP(aw)）在内的肺力学的函数，对结果指标进行了评估。ΔP(aw)、V(T)、V'(ins,max)、V'(exp,max)和V'(E)测量的相关系数r = 1.00，百分比误差<0.5%。f(R)、C(L,dyn)、R(rs,MW)、R(rs,ele)和W(OB)的相关系数r≥0.98，百分比误差<5%。过度扩张的相关系数r = 0.87，百分比误差<15%。此外，通过一种新算法准确计算了阻力。该系统在大鼠中进行了测试，其中采用肺灌洗诱导急性呼吸衰竭。灌洗后，与对照组相比，气体通气组和液体通气组的mP(aw)和W(OB)均增加，而V(T)、V'(E)、C(L,dyn)、R(rs,MW)和R(rs,ele)均降低。通气1小时后，两个损伤组的V(T)、V'(E)和C(L,dyn)均降低，而mP(aw)、R(rs,MW)、R(rs,ele)和W(OB)均增加。在肺损伤动物中，液体通气恢复了气体交换以及心血管和肺功能。我们的肺力学系统能够密切监测肺功能，包括在气体和液体阶段之间的转换过程中。
