Accuracy of IL-6 and IL-8 concentrations in exhaled breath condensate in predicting postoperative ARDS in patients undergoing cardiac surgery under cardiopulmonary bypass / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the accuracy of interleukin-6 (IL-6) and IL-8 concentrations in exhaled breath condensate (EBC) in predicting postoperative acute respiratory distress syndrome (ARDS) in the patients undergoing cardiac surgery under cardiopulmonary bypass (CPB).Methods Forty-two American Society of Anesthesiologists physical status Ⅱ or Ⅲ patients of both sexes,aged 18-64 yr,scheduled for elective cardiac valve replacement under CPB,were selected.EBC samples were collected for determination of the concentrations of IL-6 and IL-8 by enzyme-linked immunosorbent assay.The patients were divided into either ARDS group or non-ARDS group according to whether the patients developed ARDS after surgery.The receiver operating characteristic curve for IL-6 and IL-8 concentrations in EBC in diagnosing postoperative ARDS was plotted,and the area under the curve and 95％ confidence interval (CI) were calculated.The critical value,sensitivity and specificity were calculated according to the corresponding concentrations of IL-6 and IL-8 in EBC when Youden index reached the maximal value.Results Twenty-two patients developed postoperative ARDS,and the incidence was 52％.The concentrations of IL-6 and IL-8 in EBC were significantly higher at T2-4 than at T1 in two groups (P＜0.05).Compared with group nonARDS,the concentrations of IL-6 and IL-8 in EBC were significantly increased at T2-4 in group ARDS (P＜0.05).The area under the curve (95％ CI) of IL-6 concentrations in EBC measured at T2-4 in predicting postoperative ARDS was 0.822 (0.673-0.922),0.850 (0.706-0.941) and 0.906 (0.775-0.974),respectively,the critical value was 2.92,5.04 and 2.64 pg/ml,respectively,the sensitivity was 95.5％,68.2％ and 77.3％,respectively,and the specificity was 70.0％,90.0％ and 90.0％,respectively.The area under the curve (95％ CI) of IL-8 concentrations in EBC measured at Y24 in predicting postoperative ARDS was 0.700 (0.539-0.831),0.851 (0.707-0.942) and 0.737 (0.579-0.861),respectively,the critical value was 26.75,42.73 and 21.86 pg/ml,respectively,the sensitivity was 68.2％,77.3％ and 72.7％,respectively,and the specificity was 65.0％,80.0％ and 70.0％,respectively.Conclusion The concentrations of IL-6 and IL-8 in EBC can accurately predict the occurrence of postoperative ARDS in the patients undergoing cardiac surgery under CPB.