Chartrand D A, Maarek J M, Ye T H, Chang H K
Department of Biomedical Engineering, University of Southern California, Los Angeles 90089-1451.
J Appl Physiol (1985). 1990 Apr;68(4):1722-6. doi: 10.1152/jappl.1990.68.4.1722.
In eight anesthetized and tracheotomized rabbits, we studied the transfer impedances of the respiratory system during normocapnic ventilation by high-frequency body-surface oscillation from 3 to 15 Hz. The total respiratory impedance was partitioned into pulmonary and chest wall impedances to characterize the oscillatory mechanical properties of each component. The pulmonary and chest wall resistances were not frequency dependent in the 3- to 15-Hz range. The mean pulmonary resistance was 13.8 +/- 3.2 (SD) cmH2O.l-1.s, although the mean chest wall resistance was 8.6 +/- 2.0 cmH2O.l-1.s. The pulmonary elastance and inertance were 0.247 +/- 0.095 cmH2O/ml and 0.103 +/- 0.033 cmH2O.l-1.s2, respectively. The chest wall elastance and inertance were 0.533 +/- 0.136 cmH2O/ml and 0.041 +/- 0.063 cmH2O.l-1.s2, respectively. With a linear mechanical behavior, the transpulmonary pressure oscillations required to ventilate these tracheotomized animals were at their minimal value at 3 Hz. As the ventilatory frequency was increased beyond 6-9 Hz, both the minute ventilation necessary to maintain normocapnia and the pulmonary impedance increased. These data suggest that ventilation by body-surface oscillation is better suited for relatively moderate frequencies in rabbits with normal lungs.
在八只麻醉并气管切开的兔子身上，我们通过3至15赫兹的高频体表振荡研究了正常碳酸血症通气期间呼吸系统的传递阻抗。总呼吸阻抗被分为肺阻抗和胸壁阻抗，以表征每个组件的振荡力学特性。在3至15赫兹范围内，肺和胸壁的阻力与频率无关。平均肺阻力为13.8±3.2（标准差）厘米水柱·升⁻¹·秒，而平均胸壁阻力为8.6±2.0厘米水柱·升⁻¹·秒。肺弹性和惯性分别为0.247±0.095厘米水柱/毫升和0.103±0.033厘米水柱·升⁻¹·秒²。胸壁弹性和惯性分别为0.533±0.136厘米水柱/毫升和0.041±0.063厘米水柱·升⁻¹·秒²。在线性力学行为下，使这些气管切开的动物通气所需的跨肺压力振荡在3赫兹时处于最小值。随着通气频率增加到超过6至9赫兹，维持正常碳酸血症所需的分钟通气量和肺阻抗均增加。这些数据表明，对于肺部正常的兔子，体表振荡通气更适合相对适中的频率。
