Van Oosten Julien P, Francovich Juliette E, Somhorst Peter, van der Zee Philip, Endeman Henrik, Gommers Diederik A M P J, Jonkman Annemijn H
Intensive Care Volwassenen, Erasmus Medical Center, Dr. Molewaterplein 40, 3015, GD, Rotterdam, The Netherlands.
Technical Medicine Program, Delft University of Technology, Delft, The Netherlands.
Intensive Care Med Exp. 2024 Mar 19;12(1):30. doi: 10.1186/s40635-024-00616-9.
Mechanical power (MP) is the energy delivered by the ventilator to the respiratory system and combines factors related to the development of ventilator-induced lung injury (VILI). Flow-controlled ventilation (FCV) is a new ventilation mode using a constant low flow during both inspiration and expiration, which is hypothesized to lower the MP and to improve ventilation homogeneity. Data demonstrating these effects are scarce, since previous studies comparing FCV with conventional controlled ventilation modes in ICU patients suffer from important methodological concerns.
This study aims to assess the difference in MP between FCV and pressure-controlled ventilation (PCV). Secondary aims were to explore the effect of FCV in terms of minute volume, ventilation distribution and homogeneity, and gas exchange.
This is a physiological study in post-cardiothoracic surgery patients requiring mechanical ventilation in the ICU. During PCV at baseline and 90 min of FCV, intratracheal pressure, airway flow and electrical impedance tomography (EIT) were measured continuously, and hemodynamics and venous and arterial blood gases were obtained repeatedly. Pressure-volume loops were constructed for the calculation of the MP.
In 10 patients, optimized FCV versus PCV resulted in a lower MP (7.7 vs. 11.0 J/min; p = 0.004). Although FCV did not increase overall ventilation homogeneity, it did lead to an improved ventilation of the dependent lung regions. A stable gas exchange at lower minute volumes was obtained.
FCV resulted in a lower MP and improved ventilation of the dependent lung regions in post-cardiothoracic surgery patients on the ICU. Trial registration Clinicaltrials.gov identifier: NCT05644418. Registered 1 December 2022, retrospectively registered.
机械功率（MP）是呼吸机输送至呼吸系统的能量，它综合了与呼吸机诱导性肺损伤（VILI）发生相关的因素。流量控制通气（FCV）是一种在吸气和呼气过程中均采用恒定低流量的新型通气模式，据推测该模式可降低机械功率并改善通气均匀性。由于既往在ICU患者中将FCV与传统控制通气模式进行比较的研究存在重要的方法学问题，因此证明这些效果的数据较为匮乏。
本研究旨在评估FCV与压力控制通气（PCV）之间机械功率的差异。次要目的是探讨FCV在分钟通气量、通气分布与均匀性以及气体交换方面的效果。
这是一项针对ICU中需要机械通气的心胸外科术后患者的生理学研究。在基线PCV期间以及FCV 90分钟时，连续测量气管内压力、气道流量和电阻抗断层扫描（EIT），并反复获取血流动力学以及静脉和动脉血气指标。构建压力-容积环以计算机械功率。
在10例患者中，优化后的FCV与PCV相比，机械功率更低（7.7 vs. 11.0 J/分钟；p = 0.004）。虽然FCV并未提高整体通气均匀性，但确实改善了下垂肺区的通气。在较低分钟通气量时获得了稳定的气体交换。
在ICU的心胸外科术后患者中，FCV可降低机械功率并改善下垂肺区的通气。试验注册Clinicaltrials.gov标识符：NCT05644418。于2022年12月1日注册，追溯注册。
