Chi Yi, He Huai-Wu, Long Yun
Department of Critical Care Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
Chin Med J (Engl). 2020 Sep 20;133(18):2197-2204. doi: 10.1097/CM9.0000000000001018.
Mechanical power of ventilation, currently defined as the energy delivered from the ventilator to the respiratory system over a period of time, has been recognized as a promising indicator to evaluate ventilator-induced lung injury and predict the prognosis of ventilated critically ill patients. Mechanical power can be accurately measured by the geometric method, while simplified equations allow an easy estimation of mechanical power at the bedside. There may exist a safety threshold of mechanical power above which lung injury is inevitable, and the assessment of mechanical power might be helpful to determine whether the extracorporeal respiratory support is needed in patients with acute respiratory distress syndrome. It should be noted that relatively low mechanical power does not exclude the possibility of lung injury. Lung size and inhomogeneity should also be taken into consideration. Problems regarding the safety limits of mechanical power and contribution of each component to lung injury have not been determined yet. Whether mechanical power-directed lung-protective ventilation strategy could improve clinical outcomes also needs further investigation. Therefore, this review discusses the algorithms, clinical relevance, optimization, and future directions of mechanical power in critically ill patients.
通气机械功率目前被定义为一段时间内呼吸机输送到呼吸系统的能量，已被公认为是评估呼吸机诱发肺损伤和预测危重症通气患者预后的一个有前景的指标。机械功率可通过几何方法精确测量，而简化公式便于在床边轻松估算机械功率。可能存在一个机械功率的安全阈值，超过该阈值肺损伤不可避免，评估机械功率可能有助于确定急性呼吸窘迫综合征患者是否需要体外呼吸支持。应当指出，相对较低的机械功率并不排除肺损伤的可能性。肺大小和不均匀性也应予以考虑。关于机械功率的安全限度以及各组成部分对肺损伤的作用等问题尚未确定。以机械功率为导向的肺保护性通气策略能否改善临床结局也需要进一步研究。因此，本综述讨论了危重症患者机械功率的算法、临床相关性、优化及未来方向。
