Abstract：
OBJECTIVE: Airway closure is a interruption of communication between larger and smaller airways. The presence of airway closure during mechanical ventilation may lead to the overestimation of driving pressure (DP), introducing errors in the assessment of respiratory mechanics and in positive end-expiratory pressure (PEEP) setting on the ventilator. Patients with severe acute respiratory distress syndrome (ARDS) may exhibit the airway closure phenomenon, which can be easily diagnosed with a low-flow inflation. Prone positioning is a therapeutic manoeuver proven to reduce mortality in ARDS patients, and has been widely implemented also in patients requiring veno-venous extracorporeal membrane oxygenation (V-V ECMO). To date, the impact of prone positioning on changes in airway closure has not been described.
METHODS: We present an image analysis of the pressure waveform during volume-controlled ventilation and low-flow inflations before and after prone positioning in an ARDS patient on VV ECMO.
RESULTS: A high airway opening pressure level (23 cmH2O) was detected in the supine position during tidal ventilation. Airway closure was confirmed by using a low-flow inflation. Prone positioning significantly attenuated airway closure, with the airway opening pressure decreasing to 13 cmH2O. After re-supination, airway closure was lower as compared with supine position at baseline (17 cmH2O).
CONCLUSIONS: Prone positioning reduced airway closure in an ARDS patient on VV ECMO support.
METHODS: We present an image analysis of the pressure waveform during volume-controlled ventilation and low-flow inflations before and after prone positioning in an ARDS patient on VV ECMO.
RESULTS: A high airway opening pressure level (23 cmH2O) was detected in the supine position during tidal ventilation. Airway closure was confirmed by using a low-flow inflation. Prone positioning significantly attenuated airway closure, with the airway opening pressure decreasing to 13 cmH2O. After re-supination, airway closure was lower as compared with supine position at baseline (17 cmH2O).
CONCLUSIONS: Prone positioning reduced airway closure in an ARDS patient on VV ECMO support.
摘要：
目的：气道闭合是较大和较小气道之间的通讯中断。机械通气期间存在气道闭合可能导致对驱动压力（DP）的高估，在呼吸力学评估和呼吸机呼气末正压（PEEP）设置中引入错误。严重急性呼吸窘迫综合征（ARDS）患者可能出现气道闭合现象，这可以很容易地诊断为低流量通货膨胀。俯卧定位是一种治疗手段，被证明可以降低ARDS患者的死亡率，并已在需要静脉-静脉体外膜氧合（V-VECMO）的患者中广泛实施。迄今为止,俯卧位对气道闭合改变的影响尚未被描述.
方法：我们对ARDS患者VVECMO俯卧位前后的容量控制通气和低流量充气期间的压力波形进行了图像分析。
结果：在潮气通气期间在仰卧位检测到高气道开放压力水平（23cmH2O）。通过使用低流量充气确认了气道闭合。俯卧定位显著减弱气道闭合，随着气道开放压力降低至13cmH2O。在重新化闭后,基线时(17cmH2O),气道闭合率低于仰卧位.
结论：在VVECMO支持下，ARDS患者的俯卧位降低了气道闭合。
方法：我们对ARDS患者VVECMO俯卧位前后的容量控制通气和低流量充气期间的压力波形进行了图像分析。
结果：在潮气通气期间在仰卧位检测到高气道开放压力水平（23cmH2O）。通过使用低流量充气确认了气道闭合。俯卧定位显著减弱气道闭合，随着气道开放压力降低至13cmH2O。在重新化闭后,基线时(17cmH2O),气道闭合率低于仰卧位.
结论：在VVECMO支持下，ARDS患者的俯卧位降低了气道闭合。
