Department of Paediatrics, St. Marianna University School of Medicine, 2-16-1 Sugao Miyamae, Kawasaki, Kanagawa, 216-8511, Japan.
Sci Rep. 2024 Oct 29;14(1):25945. doi: 10.1038/s41598-024-77703-0.
High-frequency oscillatory ventilation (HFOV) at frequencies of approximately 15 Hz is associated with optimal CO excretion. Higher frequencies using a nitrogen-oxygen gas mixture worsen CO excretion. An in vitro experiment using HFOV and a helium-oxygen gas mixture showed a significant increase in CO transport, which increased with increases in ventilation frequency. We hypothesised that in HFOV, the change in the arterial partial pressure of CO (PaCO) would be greater at frequencies above 15 Hz when combined with helium-oxygen gas mixture administration. We tested this hypothesis in a hypoventilated healthy rabbit model by administering a helium-oxygen gas mixture at 15, 25, 35, and 45 Hz frequencies. One-way repeated measures ANOVA showed a significant decrease in PaCO among the four ventilation frequency groups. Post-hoc analysis showed significant differences between 15 and 35 Hz frequencies and between 15 and 45 Hz frequencies. The mean (standard error) decrease of PaCO was 10.8 (2.2), 14.1 (2.3), 21.3 (3.3), and 23.1 (2.5) mmHg at 15, 25, 35, and 45 Hz, respectively. Combination therapy of helium-oxygen gas mixture and high-frequency oscillation using ultra/very high frequencies (35-45 Hz) was associated with a greater PaCO decrease than that using the standard frequency (15 Hz).
高频振荡通气（HFOV）在约 15 Hz 的频率下与最佳的 CO 排出相关。使用氮-氧混合气体的更高频率会使 CO 排出恶化。使用 HFOV 和氦-氧混合气体的体外实验显示 CO 转运显著增加，并且随着通气频率的增加而增加。我们假设在 HFOV 中，当与氦-氧混合气体联合使用时，动脉血中 CO 的分压（PaCO）的变化在高于 15 Hz 的频率下会更大。我们通过在低通气健康兔模型中以 15、25、35 和 45 Hz 的频率给予氦-氧混合气体来检验这一假设。单因素重复测量方差分析显示，在四个通气频率组中 PaCO 显著降低。事后分析显示 15 和 35 Hz 频率以及 15 和 45 Hz 频率之间存在显著差异。在 15、25、35 和 45 Hz 时 PaCO 的平均（标准误差）降低分别为 10.8（2.2）、14.1（2.3）、21.3（3.3）和 23.1（2.5）mmHg。氦-氧混合气体与高频振荡的联合治疗（35-45 Hz）与使用标准频率（15 Hz）相比，PaCO 的降低更大。
