Division of Neonatology, Children's Hospital of Philadelphia Newborn Care at Pennsylvania Hospital, Philadelphia, Pennsylvania.
Division of Neonatology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
Pediatr Pulmonol. 2019 Dec;54(12):1974-1981. doi: 10.1002/ppul.24505. Epub 2019 Aug 30.
Noninvasive respiratory support continues to have high failure rates in small preterm infants. We previously demonstrated significantly improved in vitro CO washout by applying oscillations to a high flow nasal cannula system.
To develop a high frequency flow interrupter that could be applied to commonly used nasal continuous positive airway pressure (NCPAP) devices and to determine the effect of oscillations on end-tidal carbon dioxide (EtCO ) levels in an infant lung model.
DESIGN/METHODS: NCPAP was applied to a premature infant lung simulator using either bubble (BCPAP) or variable-flow (VCPAP) CPAP. Supply gas was interrupted with a solenoid pinch valve. EtCO was measured before and during oscillation and repeated at 4, 6, 8, 10, and 12 Hz oscillation and CPAP pressures of 4, 6, and 8 cm H O.
BCPAP and VCPAP EtCO levels decreased with oscillation (P < .001). BCPAP EtCO was significantly dependent on oscillation frequency (P < .001) with decreases of 18% to 47% and maximum effect at 10 Hz. Optimum VCPAP CO clearance occurred at 6 Hz with reductions of 30% and 39% at 6 and 8 cm H O CPAP respectively. BCPAP and VCPAP mean airway pressures remained unchanged transitioning from nonoscillation to oscillation. Oscillated BCPAP and VCPAP average amplitudes were 8.3 ± 0.5 and 8.4 ± 2.3 SD cm H O, respectively. Power spectrum analysis of non-oscillated BCPAP showed bubbling-only dominant peaks at 10 to 12 Hz corresponding with the maximum BCPAP EtCO reductions.
Application of high frequency oscillation to NCPAP improves CO clearance in a premature infant lung model. This simple modification to NCPAP delivery devices may prove to be an effective enhancement of this mode of noninvasive respiratory support.
无创呼吸支持在小早产儿中仍有很高的失败率。我们之前的研究表明，通过对高流量鼻导管系统施加振荡，可以显著改善 CO 的体外清除率。
开发一种高频流量中断器，可应用于常用的持续气道正压通气（CPAP）设备，并确定振荡对婴儿肺模型呼气末二氧化碳（EtCO ）水平的影响。
方法/设计：使用气泡（BCPAP）或变流量（VCPAP）CPAP 将 CPAP 施加于早产儿肺模拟器。通过电磁阀夹阀中断供应气体。在振荡前后测量 EtCO，并在 4、6、8、10 和 12 Hz 振荡和 CPAP 压力为 4、6 和 8 cm H 2 O 时重复测量。
BCPAP 和 VCPAP 的 EtCO 水平随振荡而降低（P<.001）。BCPAP 的 EtCO 与振荡频率显著相关（P<.001），降低幅度为 18%至 47%，最大效应发生在 10 Hz。VCPAP 的最佳 CO 清除率发生在 6 Hz，CPAP 为 6 和 8 cm H 2 O 时分别降低 30%和 39%。从非振荡到振荡，BCPAP 和 VCPAP 的平均气道压力保持不变。振荡的 BCPAP 和 VCPAP 的平均幅度分别为 8.3±0.5 和 8.4±2.3 SD cm H 2 O。非振荡 BCPAP 的功率谱分析显示，只有在 10 到 12 Hz 处存在冒泡主导峰值，与 BCPAP 的最大 EtCO 降低相对应。
在早产儿肺模型中，应用高频振荡可改善 CO 清除率。这种对 NCPAP 输送设备的简单改进可能是对这种无创呼吸支持模式的有效增强。
