急性肺损伤/急性呼吸窘迫综合征患者呼出气冷凝液中8-异前列腺素检测的临床意义

目的观察急性肺损伤/急性呼吸窘迫综合征（ALI/ARDS）患者呼出气冷凝液（EBC）中8-异前列腺素（8-iso-PG）的水平,探讨其临床价值。方法 2009年4月至2009年9月严重外伤和手术后入住南通大学第二附属医院重症监护病房（ICU）行机械通气的31例ALI/ARDS患者为研究组,根据入院第1 d和第5 d的病情变化,分为持续ALI组（10例）,持续ARDS组（9例）,病情加重组（ALI加重为ARDS,6例）,以及病情缓解组（ARDS缓解为ALI,6例）。对ALI/ARDS患者使用改进的EcoScreen冷凝器采集EBC标本。30名健康体检者为对照组,自主呼吸收集EBC标本。采用EIA法测定EBC中8-iso-PG浓度,观察不同肺损伤分级及预后患者EBC中8-iso-PG水平的差异,并与临床指标作相关性分析。结果 ALI/ARDS患者第1 d和第5 d时EBC中8-iso-PG水平均高于对照组[（45.53±14.37）ng/L和（45.31±12.42）ng/L比（19.47±4.06）ng/L,P〈0.001]。持续ALI组EBC中8-iso-PG水平在第1 d和第5 d时为（39.23±11.49）ng/L和（37.42±12.11）ng/L（P〉0.05）,显著低于持续ARDS组[（52.57±9.87）ng/L和（51.93±10.45）ng/L,P〉0.05）]。病情加重组EBC中8-iso-PG水平在第1 d和第5 d时分别为（32.56±9.70）ng/L和（51.43±10.93）ng/L（P〈0.05）,病情缓解组第1 d和第5 d时分别为（58.43±13.47）ng/L和（42.42±10.42）ng/L（P〈0.05）。病死组第1 d和第5 d时EBC中8-iso-PG水平为（53.94±12.25）ng/L和（57.33±10.48）ng/L,显著高于存活组[（39.16±13.65）ng/L和（36.19±7.96）ng/L,P〈0.01]。EBC中8-iso-PG水平与外周血WBC、LIS评分、X线评分、AaDO2/PaO2、AaDO2、VT、VE及MEWS评分呈正相关（P〈0.05）,与PaO2/PAO2、PaO2/FiO2呈负相关（P〈0.05）。结论 ALI患者EBC中8-iso-PG水平对判断病情严重程度和评估预后有一定的参考价值。

Clinical Significance of 8-Isoprostaglandin in Exhaled Breath Condensate of Patients with Acute Lung Injury

Objective To investigate the concentration of 8-isoprostaglandin(8-iso-PG) in exhaled breath condensate(EBC) of patients with acute lung injury/acute respiratory distress syndrome(ALI/ARDS),and evaluate its clinical significance.Methods Thirty-one ALI/ARDS patients who received mechanical ventilation were recruited as an experimental group,and EBC was collected with improved EcoScreen condenser,while thirty normal subjects were recruited as a control group.The 8-iso-PG level in EBC was analyzed by ELISA.The ALI/ARDS patients were subdivided into a continuous ALI group(n=10),a continuous ARDS group(n=9),a worsening group(n=6),and a remission group(n=6) by state of illness on 1st day and 5th day.The 8-iso-PG level in EBC of the ALI/ARDS patients with different severity and different prognosis were compared,and the correlation were analyzed between the 8-iso-PG level and clinical indicators. Results T he 8-iso-PG levels in EBC of the ALI/ARDS patients on 1st day and 5th day w ere higher than those in the control subjects respectively [(45.53±14.37) ng/ L and(45.31±12.42) ng/L vs.(19.47±4.06)ng/L,P<0.001].The 8-iso-PG level was higher in the worsening group than the remission group,higher in the contin uous ARDS group than the continuous ALI group,and higher in the non-survival g r oup than the survival group(P<0.05).The 8-iso-PG level in EBC wa s positi vely correlated with white blood cell count in peripheral blood,lung injury sco re,X-ray score,AaDO2/PaO2,AaDO2,VT,VE and MEWS s core,and negatively corr elated with PaO2/PAO2 and PaO2/FiO2.Conclusion The 8-iso-PG level in EBC of ALI/ARDS patients has reference value for judging severity and prognosis of A LI/ARDS.