1 Department of Critical Care Medicine and.
2 Department of Pulmonary Diseases, Radboud University Medical Center, Nijmegen, the Netherlands.
Am J Respir Crit Care Med. 2017 Apr 15;195(8):1033-1042. doi: 10.1164/rccm.201605-1016OC.
Controlled mechanical ventilation is used to deliver lung-protective ventilation in patients with acute respiratory distress syndrome. Despite recognized benefits, such as preserved diaphragm activity, partial support ventilation modes may be incompatible with lung-protective ventilation due to high Vt and high transpulmonary pressure. As an alternative to high-dose sedatives and controlled mechanical ventilation, pharmacologically induced neuromechanical uncoupling of the diaphragm should facilitate lung-protective ventilation under partial support modes.
To investigate whether partial neuromuscular blockade can facilitate lung-protective ventilation while maintaining diaphragm activity under partial ventilatory support.
In a proof-of-concept study, we enrolled 10 patients with lung injury and a Vt greater than 8 ml/kg under pressure support ventilation (PSV) and under sedation. After baseline measurements, rocuronium administration was titrated to a target Vt of 6 ml/kg during neurally adjusted ventilatory assist (NAVA). Thereafter, patients were ventilated in PSV and NAVA under continuous rocuronium infusion for 2 hours. Respiratory parameters, hemodynamic parameters, and blood gas values were measured.
Rocuronium titration resulted in significant declines of Vt (mean ± SEM, 9.3 ± 0.6 to 5.6 ± 0.2 ml/kg; P < 0.0001), transpulmonary pressure (26.7 ± 2.5 to 10.7 ± 1.2 cm HO; P < 0.0001), and diaphragm electrical activity (17.4 ± 2.3 to 4.5 ± 0.7 μV; P < 0.0001), and could be maintained under continuous rocuronium infusion. During titration, pH decreased (7.42 ± 0.02 to 7.35 ± 0.02; P < 0.0001), and mean arterial blood pressure increased (84 ± 6 to 99 ± 6 mm Hg; P = 0.0004), as did heart rate (83 ± 7 to 93 ± 8 beats/min; P = 0.0004).
Partial neuromuscular blockade facilitates lung-protective ventilation during partial ventilatory support, while maintaining diaphragm activity, in sedated patients with lung injury.
控制性机械通气用于为急性呼吸窘迫综合征患者提供肺保护性通气。尽管有公认的益处，例如保留膈肌活动，但由于潮气量（Vt）和跨肺压较高，部分支持通气模式可能与肺保护性通气不兼容。作为高剂量镇静剂和控制性机械通气的替代方法，膈神经机械去耦应该可以在部分通气支持模式下促进肺保护性通气。
研究部分神经肌肉阻滞是否可以在压力支持通气（PSV）和镇静下维持膈肌活动的情况下促进肺保护性通气。
在一项概念验证研究中，我们纳入了 10 名肺损伤和 PSV 下 Vt 大于 8ml/kg 且接受镇静的患者。在基线测量后，在神经调节辅助通气（NAVA）下滴定罗库溴铵以达到 6ml/kg 的目标 Vt。此后，患者在持续罗库溴铵输注下进行 2 小时 PSV 和 NAVA 通气。测量呼吸参数、血流动力学参数和血气值。
罗库溴铵滴定导致 Vt（均值±标准差，9.3±0.6 至 5.6±0.2ml/kg；P<0.0001）、跨肺压（26.7±2.5 至 10.7±1.2cmHO；P<0.0001）和膈肌电活动（17.4±2.3 至 4.5±0.7μV；P<0.0001）显著下降，并可以在持续罗库溴铵输注下维持。在滴定过程中，pH 值下降（7.42±0.02 至 7.35±0.02；P<0.0001），平均动脉血压升高（84±6 至 99±6mmHg；P=0.0004），心率也升高（83±7 至 93±8 次/分；P=0.0004）。
在镇静的肺损伤患者中，部分神经肌肉阻滞在部分通气支持下促进肺保护性通气，同时维持膈肌活动。
