Zou Xiaojing, Zhang Hongling, Wu Yongran, Li Ruiting, Gao Xuehui, Wang Azhen, Zhao Xin, Yang Xiaobo, Shu Huaqing, Qi Hong, Fu Zhaohui, Yuan Shiying, Ma Yilei, Yang Le, Shang You, Zhao Zhanqi
Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Chest. 2025 Feb;167(2):453-465. doi: 10.1016/j.chest.2024.08.050. Epub 2024 Sep 17.
The physiologic effects of different ventilation strategies on patients with ARDS need to be better understood.
In patients with ARDS receiving controlled mandatory ventilation, does airway pressure release ventilation (APRV) improve lung ventilation/perfusion (V˙/Q˙) matching and ventilation homogeneity compared with low tidal volume (LTV) ventilation?
This study was a single-center randomized controlled trial. Patients with moderate to severe ARDS were ventilated randomly with APRV or LTV ventilation. Electrical impedance tomography (EIT) was used to assess lung ventilation and perfusion. EIT-based data and clinical variables related to respiratory and hemodynamic conditions were collected shortly before randomization (0 hours) and at 12 and 24 hours after randomization.
A total of 40 patients were included and randomized to the APRV or LTV ventilation group (20 per group). During the 24-hour trial period, patients receiving APRV exhibited significantly increased dorsal ventilation (difference value [24 hours minus 0 hours]: median, 10.82% [interquartile range (IQR), 2.62%-13.74%] vs 0.12% [IQR, -2.81% to 4.76%]; P = .017), decreased dorsal shunt (median, -4.67% [IQR, -6.83% to 0.59%] vs 1.73% [IQR, -0.95% to 5.53%]; P = .008), and increased dorsal V˙/Q˙ matching (median, 4.13% [IQR, -0.26% to 10.47%] vs -3.29% [IQR, -5.05% to 2.81%]; P = .026) than those receiving LTV ventilation. No difference in ventral dead space was observed between study groups (P = .903). Additionally, two indicators of ventilation distribution heterogeneity, global inhomogeneity index and center of ventilation, significantly decreased and significantly increased, respectively, in the APRV group compared with the LTV ventilation group. Patients receiving APRV showed significantly higher Pao to Fio ratio, higher respiratory system static compliance and lower Paco than those receiving LTV ventilation at 24 hours. The cardiac output was comparable in both groups.
APRV, as compared with LTV ventilation, could recruit dorsal region, reduce dorsal shunt, increase dorsal V˙/Q˙ matching, and improve ventilation homogeneity of the lungs, leading to better gas exchange and respiratory system static compliance in patients with moderate to severe ARDS.
ClinicalTrials.gov; No.: NCT05767125; URL: www.
gov.
不同通气策略对急性呼吸窘迫综合征（ARDS）患者的生理影响尚需深入了解。
在接受控制指令通气的ARDS患者中，与低潮气量（LTV）通气相比，气道压力释放通气（APRV）是否能改善肺通气/灌注（V˙/Q˙）匹配及通气均匀性？
本研究为单中心随机对照试验。中重度ARDS患者被随机分配接受APRV或LTV通气。采用电阻抗断层成像（EIT）评估肺通气和灌注。在随机分组前即刻（0小时）以及随机分组后12小时和24小时收集基于EIT的数据以及与呼吸和血流动力学状况相关的临床变量。
共纳入40例患者并随机分为APRV组或LTV通气组（每组20例）。在24小时试验期内，接受APRV的患者与接受LTV通气的患者相比，背部通气显著增加（差值[24小时减去0小时]：中位数为10.82%[四分位间距（IQR），2.62%-13.74%] vs 0.12%[IQR，-2.81%至4.76%]；P = 0.017），背部分流减少（中位数为-4.67%[IQR，-6.83%至0.59%] vs 1.73%[IQR，-0.95%至5.53%]；P = 0.008），背部V˙/Q˙匹配增加（中位数为4.13%[IQR，-0.26%至10.47%] vs -3.29%[IQR，-5.05%至2.81%]；P = 0.026）。研究组间腹侧无效腔无差异（P = 0.903）。此外，与LTV通气组相比，APRV组通气分布异质性的两个指标，即全局不均匀性指数和通气中心，分别显著降低和显著增加。在24小时时，接受APRV的患者比接受LTV通气的患者具有显著更高的动脉血氧分压与吸入氧分数值之比、更高的呼吸系统静态顺应性和更低的动脉血二氧化碳分压。两组的心输出量相当。
与LTV通气相比，APRV可使背部区域复张，减少背部分流，增加背部V˙/Q˙匹配，并改善肺通气均匀性，从而使中重度ARDS患者气体交换更好，呼吸系统静态顺应性更佳。
ClinicalTrials.gov；编号：NCT05767125；网址：www.clinicaltrials.gov
