Department of Medical Engineering, National Hospital Organization Yamaguchi Ube Medical Center, Ube, Japan.
Department of Clinical Research, National Hospital Organization Yamaguchi Ube Medical Center, Ube, Japan.
Respir Care. 2024 Aug 24;69(9):1092-1099. doi: 10.4187/respcare.11249.
Intrapulmonary percussive ventilation (IPV) is frequently used for airway clearance, together with delivery of aerosolized medications. Drug delivery via IPV alone increases with decreasing percussion frequency and correlates with tidal volume ([Formula: see text]), whereas drug delivery via IPV during invasive ventilation is not well characterized. We hypothesized that drug delivery via IPV-invasive ventilation would differ from IPV alone due to control of ventilation by invasive ventilation.
An adult ventilator circuit was used for IPV-invasive ventilation. A normal or a diseased lung model was configured to airway resistance of 5 cm HO/L/s and lung compliance of 100 mL/cm HO or to airway resistance of 20 cm HO/L/s and lung compliance of 50 mL/cm HO, respectively. The ventilator settings were the following: pressure control continuous mandatory ventilation mode, 10 breaths/min; PEEP, 5 cm HO; [Formula: see text], 0.21; inspiratory time, 1 s; no bias flow; and inspiratory pressure, 10 or 15 cm HO for the normal or the diseased lung model, respectively, to reach [Formula: see text] 500 mL with IPV off. Albuterol nebulized from an IPV device was captured in a filter placed before the lung model and quantitated by spectrophotometry.
The maximum efficiency of albuterol delivery via IPV-invasive ventilation was not different from that via IPV alone (mean ± SD of loading dose, 3.7 ± 0.2% vs 4.2 ± 0.3%, respectively; = .12). The mean ± SD albuterol delivery efficiency with IPV-invasive ventilation was lower for the diseased lung model versus the normal model (1.6 ± 0.3% vs 3.2 ± 0.5%; < .001), which increased with decreasing percussion frequency. In contrast, the mean ± SD [Formula: see text] was lower for the normal lung model versus the diseased model (401 ± 14 mL vs 470 ± 11 mL; < .001).
Albuterol delivery via IPV-invasive ventilation was modulated by percussion frequency but was not increased with increasing [Formula: see text]. The delivery efficiency was not sufficiently high for clinical use, in part due to nebulizer retention and extrapulmonary deposition.
肺内叩击通气（IPV）常用于气道清除，并同时输送雾化药物。单独使用 IPV 输送药物的效果会随着叩击频率的降低而增加，并与潮气量呈正相关([公式：见正文])，而在有创通气期间通过 IPV 输送药物的效果尚未得到很好的描述。我们假设由于有创通气可以控制通气，因此通过 IPV-有创通气输送药物的效果会与单独使用 IPV 有所不同。
使用成人呼吸机回路进行 IPV-有创通气。配置正常或患病的肺模型，使其气道阻力分别为 5 cm HO/L/s 和肺顺应性为 100 mL/cm HO，或气道阻力为 20 cm HO/L/s 和肺顺应性为 50 mL/cm HO。呼吸机设置如下：压力控制连续强制通气模式，10 次/分钟；呼气末正压 5 cm HO；吸入氧浓度 0.21；吸气时间 1 秒；无偏流；吸气压力分别为 10 或 15 cm HO，用于正常或患病肺模型，以使 IPV 关闭时潮气量达到 500 mL。通过 IPV 设备雾化的沙丁胺醇被放置在肺模型前的过滤器截留，并通过分光光度法定量。
通过 IPV-有创通气输送沙丁胺醇的最大效率与单独使用 IPV 时没有差异（负荷剂量的平均值±标准差，分别为 3.7±0.2%和 4.2±0.3%；=.12）。与正常模型相比，使用 IPV-有创通气输送沙丁胺醇的效率在患病肺模型中较低（平均值±标准差，1.6±0.3%和 3.2±0.5%；<.001），随着叩击频率的降低而增加。相比之下，正常肺模型的平均[公式：见正文]比患病模型低（401±14 mL 和 470±11 mL；<.001）。
通过 IPV-有创通气输送沙丁胺醇的效果可通过叩击频率调节，但不会随着[公式：见正文]的增加而增加。输送效率不够高，无法用于临床，部分原因是雾化器保留和肺外沉积。
