Zhang Yingying, Wittenstein Jakob, Braune Anja, Theilen Raphael, Maiello Lorenzo, Benzi Giulia, Bluth Thomas, Kiss Thomas, Ran Xi, Koch Thea, Rocco Patricia R M, Schultz Marcus J, Kotzerke Jörg, Gama De Abreu Marcelo, Huhle Robert, Scharffenberg Martin
Department of Anesthesiology and Intensive Care Medicine, Pulmonary Engineering Group, Faculty of Medicine and University Hospital Carl Gustav Carus, TUD Dresden University of Technology, Dresden, Germany.
Department of Anesthesiology, Affiliated Hospital of Southwest Medical University, Luzhou, China.
Front Physiol. 2024 Oct 15;15:1462954. doi: 10.3389/fphys.2024.1462954. eCollection 2024.
Despite being essential in patients with acute respiratory distress syndrome (ARDS), mechanical ventilation (MV) may cause lung injury and hemodynamic instability. Mechanical power (MP) may describe the net injurious effects of MV, but whether it reflects the hemodynamic effects of MV is currently unclear. We hypothesized that MP is also associated with cardiac output (CO) and pulmonary blood flow (PBF).
24 anesthetized pigs with experimental acute lung injury were ventilated for 18 h according to one of three strategies: 1) Open lung approach (OLA), 2) ARDS Network high-PEEP/FO strategy (HighPEEP), or 3) low-PEEP/FO strategy (LowPEEP). Total MP was assessed as the sum of energy dissipated to overcome airway resistance and energy temporarily stored in the elastic lung tissue per minute. The distribution of pulmonary perfusion was determined by positron emission tomography. Regional PBF and MP, assessed in three iso-gravitational regions of interest (ROI) with equal lung mass (ventral, middle, and dorsal ROI), were compared between groups.
MP was higher in the LowPEEP than in the OLA group, while CO did not differ between groups. After 18 h, regional PBF did not differ between groups. During LowPEEP, regional MP was higher in the ventral ROI compared to OLA and HighPEEP groups (2.5 ± 0.3 vs. 1.4 ± 0.4 and 1.6 ± 0.3 J/min, respectively, P < 0.001 each), and higher in the middle ROI compared to the OLA group (2.5 ± 0.4 vs. 1.6 ± 0.5 J/min, = 0.04). MP in the dorsal ROI did not differ between groups (1.4 ± 0.9 vs. 1.4 ± 0.5 vs. 1.3 ± 0.8 J/min, = 0.916). Total MP was independently associated with CO [0.34 (0.09, 0.59), = 0.020]. Regional MP was positively associated with PBF irrespective of the regions [0.52 (0.14, 0.76), = 0.01; 0.49 (0.10, 0.74), = 0.016; 0.64 (0.32, 0.83), = 0.001 for ventral, middle, and dorsal ROI, respectively]. Subgroup analysis revealed a significant association of MP and CO only in the OLA group as well as a significant association between MP with regional PBF only in the HighPEEP group.
In this model of acute lung injury in pigs ventilated with either open lung approach, high, or low PEEP tables recommended by the ARDS network, MP correlated positively with CO and regional PBF, whereby these clinically relevant lung-protective ventilation strategies influenced the associations.
尽管机械通气（MV）对急性呼吸窘迫综合征（ARDS）患者至关重要，但它可能导致肺损伤和血流动力学不稳定。机械功率（MP）可能描述了MV的净损伤效应，但目前尚不清楚它是否反映了MV的血流动力学效应。我们假设MP也与心输出量（CO）和肺血流量（PBF）相关。
24只患有实验性急性肺损伤的麻醉猪按照三种策略之一进行18小时通气：1）开放肺通气法（OLA），2）ARDS网络高呼气末正压/低吸气末正压策略（HighPEEP），或3）低呼气末正压/低吸气末正压策略（LowPEEP）。总MP被评估为每分钟克服气道阻力所耗散的能量与暂时储存在弹性肺组织中的能量之和。通过正电子发射断层扫描确定肺灌注分布。比较三组在三个等重力感兴趣区域（ROI）（腹侧、中间和背侧ROI）中评估的区域PBF和MP，这些区域具有相等的肺质量。
LowPEEP组的MP高于OLA组，而各组之间的CO无差异。18小时后，各组之间的区域PBF无差异。在LowPEEP期间，腹侧ROI的区域MP高于OLA组和HighPEEP组（分别为2.5±0.3 vs. 1.4±0.4和1.6±0.3 J/min，P均<0.001），中间ROI的区域MP高于OLA组（2.5±0.4 vs. 1.6±0.5 J/min，P = 0.04）。背侧ROI的MP在各组之间无差异（1.4±0.9 vs. 1.4±0.5 vs. 1.3±0.8 J/min，P = 0.916）。总MP与CO独立相关[0.34（0.09，0.59），P = 0.020]。无论区域如何，区域MP与PBF呈正相关[腹侧、中间和背侧ROI分别为0.52（0.14，0.76），P = 0.01；0.49（0.10，0.74），P = 0.016；0.64（0.32，0.83），P = 0.001]。亚组分析显示，仅在OLA组中MP与CO存在显著关联，仅在HighPEEP组中MP与区域PBF存在显著关联。
在采用开放肺通气法、ARDS网络推荐的高或低呼气末正压通气方案对猪进行通气的急性肺损伤模型中，MP与CO和区域PBF呈正相关，这些具有临床相关性的肺保护性通气策略影响了这种关联。
