目的:分析基于功能残气量（FRC）指导最佳呼气末正压（PEEP）在急性呼吸窘迫综合征（ARDS）患者肺复张过程中的应用，探讨FRC与跨肺压的相关性以及二者对预后的预测价值。方法:选择2018年3月至2019年5月锦州医科大学附属第一医院重症医学科收治的78例ARDS机械通气患者，并按随机数字表法分为试验组（41例）和对照组（37例），所有患者在充分镇静后均予渐进式增加PEEP进行肺复张，其中试验组通过监测FRC设置最佳PEEP，对照组则通过最大氧合法设置最佳PEEP。比较两组肺复张前及肺复张后30 min和2 h动态顺应性（Cdyn）、氧合指数（PaOn 2/FiOn 2）、机械功（MP）的差异；采用Pearson法分析FRC与跨肺压的相关性；采用受试者工作特征曲线（ROC）评估FRC和跨肺压对ARDS患者28 d病死率的预测价值。n 结果:试验组肺复张后最佳PEEP为（16.24±1.57）cmHn 2O（1 cmHn 2O＝0.098 kPa），对照组最佳PEEP为（14.11±1.15）cmHn 2O，两组比较差异有统计学意义（n t＝5.678，n P＝0.000）。Pearson相关分析显示，ARDS患者FRC与跨肺压存在显著相关性（n r＝0.759，n P＝0.000）。试验组肺复张后30 min和2 h的Cdyn、PaOn 2/FiOn 2均明显高于对照组〔Cdyn（mL/cmHn 2O）：61.16±3.55比58.54±5.25，58.59±2.82比56.86±3.40；PaOn 2/FiOn 2（mmHg，1 mmHg＝0.133 kPa）：245.27±14.86比239.00±5.34，192.25±5.11比188.86±5.07〕，MP均明显低于对照组（J/min：16.32±1.11比17.05±1.22，15.22±1.25比17.03±1.50），差异均有统计学意义（均n P<0.05）。ROC曲线分析显示，FRC和跨肺压对ARDS患者28 d病死率均有预测价值，其ROC曲线下面积（AUC）分别为0.868、0.828（均n P<0.01）。n 结论:ARDS患者在肺复张过程中监测FRC可指导最佳PEEP；FRC与跨肺压具有显著相关性，并且二者对ARDS患者28 d病死率均具有预测价值。“,”Objective:To analyze the application of functional residual capacity (FRC)-guided optimal positive end-expiratory pressure (PEEP) in pulmonary retention in patients with acute respiratory distress syndrome (ARDS), and to explore the correlation between FRC and trans-pulmonary pressure and their predictive value for prognosis.Methods:Seventy-eight ARDS patients on mechanical ventilation admitted to department of critical care medicine of the First Affiliated Hospital of Jinzhou Medical University from March 2018 to May 2019 were enrolled. According to random number table method, the patients were divided into experimental group and the control group. PEEP of all patients were gradually increased in recruitment after fully sedation and analgesia. The best PEEP was set by monitoring FRC in the experimental group, and by monitoring maximum oxygen in the control group set. The differences before and after 30 minutes and 2 hours recruitment manoeuvres in dynamic compliance (Cdyn), oxygenation index (PaOn 2/FiOn 2), and mechanical power (MP) were compared between the two groups. Pearson method was used to analyze the correlation between FRC and trans-pulmonary pressure. The predictive value of FRC and trans-pulmonary pressure for 28-day mortality in patients with ARDS was analyzed by receiver operating characteristic (ROC) curve.n Results:The optimal PEEP was (16.24±1.57) cmHn 2O (1 cmHn 2O = 0.098 kPa) in the experimental group and (14.11±1.15) cmHn 2O in the control group in recruitment maneuvres, with statistically significant difference between the two groups (n t = 5.678, n P = 0.000). Pearson correlation analysis showed that there was a significant correlation between FRC and trans-pulmonary pressure in ARDS patients (n r = 0.759, n P = 0.000). Cdyn and PaOn 2/FiOn 2 in the experimental group were higher than the control group at 30 minutes and 2 hours after recruitment maneuvres [Cdyn (mL/cmHn 2O): 61.16±3.55 vs. 58.54±5.25, 58.59±2.82 vs. 56.86±3.40; PaOn 2/FiOn 2 (mmHg, 1 mmHg = 0.133 kPa): 245.27±14.86 vs. 239.00±5.34, 192.25±5.11 vs. 188.86±5.07], MP was lower than the control group (J/min: 16.32±1.11 vs. 17.05±1.22, 15.22±1.25 vs. 17.03±1.50), the difference was statistically significant (all n P < 0.05). The ROC curve analysis showed that both FRC and trans-pulmonary pressure had predictive value for the 28-day mortality of ARDS patients, and the area under the ROC curve (AUC) was 0.868, and 0.828 respectively (both n P < 0.01).n Conclusions:Measuring FRC in patients with ARDS during recruitment maneuvres can guide optimal PEEP. FRC was significantly correlated with trans-pulmonary pressure, and both of them had predictive value for 28-day mortality in ARDS patients.