Friesecke Sigrun, Stecher Stephanie-Susanne, Abel Peter
Department of Internal Medicine B, Division of Cardiology, Pneumology and Critical Care Medicine, University Medicine Greifswald, Ferdinand-Sauerbruch-Straße, 17475, Greifswald, Germany.
Crit Care. 2015 May 1;19(1):201. doi: 10.1186/s13054-015-0935-4.
High-frequency oscillation ventilation (HFOV) is regarded as particularly lung protective. Recently, HFOV has been shown to be not beneficial for acute respiratory distress syndrome (ARDS) patients in general. Due to its special physical effects, it could be beneficial, however, in inhomogeneous ARDS. This study evaluates the effect of HFOV on PaCO2 removal in hypercapnic patients with ARDS of pulmonary origin.
Between October 2010 and June 2014 patients with ARDS of pulmonary origin with PaO2/FiO2 ratio >60 mmHg, but respiratory acidosis (pH <7.26) under optimized protective ventilation were switched to HFOV, using moderate airway pressure (adopting the mean airway pressure of the prior ventilation). Data from these patients were analyzed retrospectively; PaCO2 and pH before, 1 h and 24 h after the start of HFOV were compared.
Twenty-six patients with PaO2/FiO2 ratio 139 ± 49 and respiratory acidosis (PaCO2 68 ± 12 mmHg) were put on HFOV after 17 ± 22 h of conventional ventilation. Mean airway pressure was 19 cm H2O (15 to 28). PaCO2 decreased significantly: after 1 hour the mean difference was -14 ± 10 mmHg; P <0.01 and after 24 hours -17 ± 12 mmHg; P <0.01; n = 24. CO2 clearance improved in all but two patients; in those, extracorporeal lung support was initiated. Oxygenation remained unchanged after 1 h and slightly increased after 24 h. No complications related to HFOV were observed. Twenty-two patients improved and could be weaned from HFOV. Twenty patients (77%) were alive on day 30.
HFOV could be a useful alternative in patients with ARDS of pulmonary origin with hypercapnic failure of lung-protective conventional ventilation.
高频振荡通气（HFOV）被认为具有特别的肺保护作用。最近，总体而言，HFOV已被证明对急性呼吸窘迫综合征（ARDS）患者并无益处。然而，由于其特殊的物理效应，在不均匀性ARDS中可能有益。本研究评估了HFOV对肺源性ARDS高碳酸血症患者二氧化碳分压（PaCO₂）清除的影响。
在2010年10月至2014年6月期间，将肺源性ARDS患者，其氧合指数（PaO₂/FiO₂）>60 mmHg，但在优化的保护性通气下存在呼吸性酸中毒（pH<7.26），转换为HFOV，采用中等气道压力（采用先前通气的平均气道压力）。对这些患者的数据进行回顾性分析；比较HFOV开始前、开始后1小时和24小时的PaCO₂和pH值。
26例氧合指数为139±49且存在呼吸性酸中毒（PaCO₂ 68±12 mmHg）的患者在常规通气17±22小时后接受HFOV治疗。平均气道压力为19 cm H₂O（15至28）。PaCO₂显著下降：1小时后平均差值为-14±10 mmHg；P<0.01，24小时后为-17±12 mmHg；P<0.01；n = 24。除两名患者外，所有患者的二氧化碳清除均得到改善；这两名患者开始进行体外肺支持。氧合在1小时后保持不变，24小时后略有增加。未观察到与HFOV相关的并发症。22例患者病情改善，可撤离HFOV。20例患者（77%）在第30天存活。
对于肺源性ARDS且肺保护性常规通气出现高碳酸血症衰竭的患者，HFOV可能是一种有用的替代方法。
