International Centre for Circulatory Health, St. Mary's Hospital and Imperial College, London, United Kingdom.
J Am Coll Cardiol. 2010 Nov 23;56(22):1832-7. doi: 10.1016/j.jacc.2010.05.053.
This study targeted carbon dioxide (CO(2)) oscillations seen in oscillatory ventilation with dynamic pre-emptive CO(2) administration.
Oscillations in end-tidal CO(2) (et-CO(2)) drive the ventilatory oscillations of periodic breathing (PB) and central sleep apnea in heart failure (HF).
Seven healthy volunteers simulated PB, while undergoing dynamic CO(2) administration delivered by an automated algorithm at different concentrations and phases within the PB cycle. The algorithm was then tested in 7 patients with HF and PB.
In voluntary PB, the greatest reduction (74%, p < 0.0001) in et-CO(2) oscillations was achieved when dynamic CO(2) was delivered at hyperventilation; when delivered at the opposite phase, the amplitude of et-CO(2) oscillations increased (35%, p = 0.001). In HF patients, oscillations in et-CO(2) were reduced by 43% and ventilatory oscillations by 68% (both p < 0.05). During dynamic CO(2) administration, mean et-CO(2) and ventilation levels remained unchanged. Static CO(2) (2%, constant flow) administration also attenuated spontaneous PB in HF patients (p = 0.02) but increased mean et-CO(2) (p = 0.03) and ventilation (by 45%, p = 0.03).
Dynamic CO(2) administration, delivered at an appropriate time during PB, can almost eliminate oscillations in et-CO(2) and ventilation. This dynamic approach might be developed to treat central sleep apnea, as well as minimizing undesirable increases in et-CO(2) and ventilation.
本研究针对的是具有动态预充 CO₂功能的振荡通气中观察到的二氧化碳（CO₂）振荡。
呼气末 CO₂（et-CO₂）的波动驱动心力衰竭（HF）中周期性呼吸（PB）和中枢性睡眠呼吸暂停的通气波动。
7 名健康志愿者在不同的 PB 周期内的浓度和相位下，通过自动算法进行动态 CO₂给药，模拟 PB。然后，该算法在 7 名 HF 合并 PB 的患者中进行了测试。
在自愿性 PB 中，当动态 CO₂在过度通气时给药时，et-CO₂波动的最大降幅（74%，p<0.0001）；当在相反的阶段给药时，et-CO₂波动的振幅增加（35%，p=0.001）。在 HF 患者中，et-CO₂波动降低了 43%，通气波动降低了 68%（均 p<0.05）。在动态 CO₂给药期间，平均 et-CO₂和通气水平保持不变。静态 CO₂（2%，恒流）给药也能减弱 HF 患者的自发性 PB（p=0.02），但增加了平均 et-CO₂（p=0.03）和通气（增加 45%，p=0.03）。
在 PB 期间适当时间给予动态 CO₂给药可几乎消除 et-CO₂和通气的波动。这种动态方法可用于治疗中枢性睡眠呼吸暂停，同时最大限度地减少 et-CO₂和通气的不期望增加。
