Marrazzo Francesco, Spina Stefano, Zadek Francesco, Forlini Clarissa, Bassi Gabriele, Giudici Riccardo, Bellani Giacomo, Fumagalli Roberto, Langer Thomas
Department of Anesthesia and Critical Care, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milano, Italy.
School of Medicine and Surgery, University of Milano-Bicocca, 20126 Milano, Italy.
J Clin Med. 2023 Jun 8;12(12):3914. doi: 10.3390/jcm12123914.
Changing trunk inclination affects lung function in patients with ARDS. However, its impacts on PEEP titration remain unknown. The primary aim of this study was to assess, in mechanically ventilated patients with COVID-19 ARDS, the effects of trunk inclination on PEEP titration. The secondary aim was to compare respiratory mechanics and gas exchange in the semi-recumbent (40° head-of-the-bed) and supine-flat (0°) positions following PEEP titration.
Twelve patients were positioned both at 40° and 0° trunk inclination (randomized order). The PEEP associated with the best compromise between overdistension and collapse guided by Electrical Impedance Tomography (PEEP) was set. After 30 min of controlled mechanical ventilation, data regarding respiratory mechanics, gas exchange, and EIT parameters were collected. The same procedure was repeated for the other trunk inclination.
PEEP was lower in the semi-recumbent than in the supine-flat position (8 ± 2 vs. 13 ± 2 cmHO, < 0.001). A semi-recumbent position with optimized PEEP resulted in higher PaO:FiO (141 ± 46 vs. 196 ± 99, = 0.02) and a lower global inhomogeneity index (46 ± 10 vs. 53 ± 11, = 0.008). After 30 min of observation, a loss of aeration (measured by EIT) was observed only in the supine-flat position (-153 ± 162 vs. 27 ± 203 mL, = 0.007).
A semi-recumbent position is associated with lower PEEP and results in better oxygenation, less derecruitment, and more homogenous ventilation compared to the supine-flat position.
改变躯干倾斜度会影响急性呼吸窘迫综合征（ARDS）患者的肺功能。然而，其对呼气末正压（PEEP）滴定的影响尚不清楚。本研究的主要目的是评估在机械通气的新型冠状病毒肺炎（COVID-19）ARDS患者中，躯干倾斜度对PEEP滴定的影响。次要目的是比较PEEP滴定后半卧位（床头抬高40°）和仰卧平卧位（0°）时的呼吸力学和气体交换情况。
12例患者分别处于躯干倾斜度40°和0°的体位（随机顺序）。根据电阻抗断层成像（EIT）指导，设置在过度扩张和肺萎陷之间达到最佳平衡的PEEP。在控制机械通气30分钟后，收集有关呼吸力学、气体交换和EIT参数的数据。对另一种躯干倾斜度重复相同的操作。
半卧位时的PEEP低于仰卧平卧位（8±2 vs. 13±2 cmH₂O，P<0.001）。优化PEEP后的半卧位导致更高的动脉血氧分压与吸入氧分数值（PaO₂:FiO₂）（141±46 vs. 196±99，P=0.02）和更低的整体不均匀指数（46±10 vs. 53±11，P=0.008）。观察30分钟后，仅在仰卧平卧位观察到通气丧失（通过EIT测量）（-153±162 vs. 27±203 mL，P=0.007）。
与仰卧平卧位相比，半卧位与更低的PEEP相关，且导致更好的氧合、更少的肺不张和更均匀的通气。
