俯卧位肺部超声检查预测急性呼吸窘迫综合征患者俯卧位通气的预后价值

The value of prone position lung ultrasound examination in predicting the prognosis of acute respiratory distress syndrome receiving prone ventilation

目的 探讨俯卧位肺部超声检查（PLUE）预测急性呼吸窘迫综合征（ARDS）患者俯卧位通气的预后价值.方法 需行俯卧位通气的ARDS患者,在首次行俯卧位通气即刻、府卧位3h行肺部超声检查（肺部16个区域）,观察肺重力依赖区通气的变化,计算肺通气评分和肺通气评分变化值（ASV）,采用ROC判断ASV预测患者俯卧位通气治疗效果与能否脱机的截止值（cutoff值）.结果 29例ARDS患者俯卧位通气3h后肺重力依赖区的总肺通气评分较俯卧位即刻明显下降[（19.15±7.98）分比（26.96±6.43）分;P＜0.01],氧合指数明显升高[（190±65） mmHg（1 mmHg=0.133kPa）比（168±64） mmHg,P＜0.01].7d时治疗有效组（氧合指数＞300 mmHg）的ASV明显高于治疗无效组（氧合指数＜300 mmHg）[（9.53±4.34）分比（4.86±2.96）分;P＜0.05],脱机组ASV明显高于未脱机组[（10.17±4.45）分比（5.23±3.03）分;P＜0.05].28 d时存活组ASV为（7.90±4.63）分,死亡组为（5.89±3.59）分,差异无统计学意义（P＞0.05）.ASV评估俯卧位通气7d时治疗有效的AUCROC为0.84,若以ASV≥5.5分预测俯卧位通气7d时治疗是否有效的灵敏度为86.7％,特异度为71.4％.ASV评估俯卧位通气7d时能够脱机的AUCROc为0.824,若以ASV≥7分预测卧位通气7d时能否脱机的灵敏度为75.0％,特异度为76.5％.结论 PLUE可有效评估ARDS患者俯卧位时肺重力依赖区的肺通气改变.俯卧位通气3 h PLUE可以预测ARDS患者俯卧位通气7d内治疗是否有效及能否脱机,其对病死率的预测价值需进一步研究.

Objective To investigate the value of prone position lung ultrasound examination （PLUE） in monitoring the prone position during and predicting the outcome of Acute Respiratory Distress Syndrome （ARDS） patients.Methods All the ARDS patients needed to receive prone position were enrolled,a three hours PLUE was performed during the prone position for the first time.For each of the 16 regions examined,ultrasound patterns were recorded and the aeration scores were calculated at the beginning of the prone position and 3 hours later.The correlation of the aeration score variation （ASV） and the oxygen fraction were evaluated.The relationship between the ASV and the outcome indexes such as oxygen fraction,free of mechanical ventilation and mortality were also evaluated.Results A total of 29 patients were enrolled in this study.The aeration score of the lung was significantly reduced three hours after the beginning than the beginning（19.15 ±7.98 vs 26.96 ±6.43,P 〈0.01）,with the significant increasing of the oxygen fraction.The ASV was significantly higher in the patients with oxygen fractions 〉 300 mmHg （1 mmHg =0.133 kPa） in Day 7 than those with oxygen fractions 〈 300 mmHg（9.53 ± 4.34 vs 4.86 ± 2.96,P 〈=0.05）.The ASV was also higher in the patients free of mechanical ventilation in Day 7 than those who needed mechanical ventilation （10.17 ± 4.45 vs 5.23 ± 3.03,P 〈 0.05）.The area under the receiver operating characteristic curve was 0.840 and 0.824 respectively for detecting the validity of the prone position and the possibility of free of mechanical ventilation with ASV.For predicting the oxygen fraction 〉300 mmHg in Day 7,the cutoff value of ASV was ≥5.5,resulting a sensitivity of 86.7% and a specificity of 71.4%.For predicting the patients free of mechanical ventilation in Day 7,the cutoff value of ASV was 7,resulting a sensitivity of 75.0% and a specificity of 76.5%.Conclusion Bedside lung ultrasound is valuable in evaluating the ASV during the prone position in ARDS patients.The three hours PLUE can predict the outcome of ARDS patients such as validity of prone position and free of ventilation in Day 7.The value of predicting the mortality needs further investigation.