死腔分数对急性呼吸窘迫综合征患者预后的评估作用

目的 探讨死腔分数 (VD/VT) 对急性呼吸窘迫综合征 (ARDS) 患者预后的评估作用.方法 采用前瞻性临床研究于2015年1月至2016年8月收集符合柏林标准的机械通气ARDS患者32例.自入EICU起连续6天测定PaCO2、ETCO2, 计算VD/VT, 同时收集患者一般情况、生命体征、急性生理和慢性健康评分 (APACHEⅡ) 、肺损伤预测评分 (LIPS) 、PaO2/FiO2等, 随访28 d病死率;根据预后分存活组和死亡组, 探讨死腔分数 (VD/VT) 在急性呼吸窘迫综合征 (ARDS) 患者预后评估中作用.结果 ARDS患者VD/VT均升高, 入院1~3 d VD/VT 2组间差异无统计学意义, 而4~6 d死亡组均高于存活组 (P<0.001) , 第4天VD/VT死亡组较存活组明显增高.ROC曲线显示:第4天预测ARDS预后的ROC曲线下面积 (AUC) 为0.910, 高于APACHEⅡ和LIPS评分, 以0.62为临界值预测预后的敏感性和特异性分别为:0.916和0.955.结论 死腔分数为ARDS预后的危险因素, 第4天死腔分数对预后评估有指导价值.

Prognostic Value of the Pulmonary Dead-space Fraction in Patients of Acute Respiratory Distress Syndrome

Objective To investigate the effect of pulmonary dead-space fraction on the prognosis of acute respiratory distress syndrome (ARDS) . Me thods 32 patients meeting ARDS Berlin definition, who were admitted to the EICU from January 2015 to August 2016, were analyzed with a prospective method. The VD/VT was measured by the single breath test of CO2. (day6 from day1) . Patients' general condition, vital signs, APACHEⅡ, LIPS, Pa O2/Fi O2, 28-day mortality were recorded.The patients were divided into a survival group and a death group according to their survival situation in 28 days. Re s ults Comparison of VD/VT between the death group and the survival group of ARDS patients at different time point: VD/VT was elevated in the two groups.VD/VT showed no statistical difference from the 1st day to the 3th day after admission, but higher in the death group from the 4th day to the 6th day after admission (P<0.01) .VD/VT was significantly higher in non survivors than in survivors from the 4th day of mechanical ventilation. ROC curve and 28-day survival curve showed that the area under ROC curve of VD/VT predicting prognosis of patients with ARDS was 0.910, higher than APACHEⅡand LIPS. When the optimal cut off value was 0.62, the sensitivity was 0.916, and specificity was 0.955. Conclus ion VD/VT is a risk factor of patients 28 day prognosis, VD/VT of the 4th day of ARDS is associated with greater risk of death.