中心静脉血氧饱和度对心肺复苏后血流动力学不稳定患者容量反应性的预测价值

Central venous saturation is a predictor of fluid responsiveness in hemodynamically unstable patients after cardiopulmonary resuscitation

目的 探讨中心静脉血氧饱和度（ScvO2）在容量复苏前后的变异是否可以成为判断心肺复苏后血流动力学不稳定患者对液体治疗有无反应的一个预测指标。方法 采用前瞻性临床研究方法，对入选的39例心肺复苏后血流动力学不稳定患者在自主循环恢复（ROSC）后约1h进行第1次容量复苏；在ROSC后约2~6h，对其中的24例符合2次入选的患者进行了第2次液体负荷试验。所有患者均放置桡动脉插管、双腔锁骨下静脉或颈内静脉置管和脉波指示剂连续心排血量（PiCCO）导管。在每一次容量复苏前后都测定了平均动脉压（MAP）、中心静脉压（CVP）、心脏指数（CI）及ScvO2。将液体负荷后CI增加值（△CI）≥15%定义为液体反应阳性。结果 2次容量复苏后△ScvO2与△CI的直线相关分析呈显著相关；2次测得的△ScvO2受试者工作特征性（ROC）曲线分别显示：4.4%和4.2%可作为△ScvO2的阈值去鉴别患者对容量治疗是否有反应性，其曲线下面积（AUC）分别为0.848和0.921；而2次总的的△ScvO2的阈值为4.3%，其AUC为0.877。结论 容量复苏前后的ScvO2的变异可以预测心肺复苏后血流动力学不稳定患者对液体治疗是否有效；与ROSC后约1h相比，2～6h的测定值对于容量反应性的鉴别能力有升高趋势。

Objective To assess the predictive value of central venous saturation variations （△ScvO2） after volume ex-pansion （VE） for fluid responsiveness in hemodynamically unstable patients after cardiopulmonary resuscitation. Methods Thirty nine hemodynamical y unstable patients received fluid resuscitation after cardiopulmonary resuscitation. Al patients had central venous catheter, radial arterial line and pulse indicator continuous cardiac output （PiCCO） catheters indwel ed. Hemodynamic measurements were performed before and after a two- step fluid bolus at 1 （39 cases） and 2~6h （24 cases） after return to spon-taneous circulation （ROSC）. Fluid responsiveness was defined by an increase in stroke volume of at least 15%. Cardiac index （CI） and ScvO2 changes after VE were analyzed using linear regression. Receiver operating characteristics curve analysis was used to test their ability to distinguish responder （R） and non- responder （NR）. Results △ScvO2 after VE was significantly correlated with△CI after VE （r=0.833, P〈0.001）. Central venous pressure variation（△CVP） was not associated with fluid responsiveness. In contrast, variation of mean blood pressure （△MAP） and△ScvO2 were able to predict fluid responsiveness, and the area under the curve （AUC） was 0.704 （P=0.030） and 0.848 （P=0.000） at 1h, 0.821 （P=0.008） and 0.921（P=0.000） at 2- 6h after ROSC, re-spectively. Compared with those at 1h,△MAP and△ScvO2 at 2- 6h had tendency of higher ability to predict fluid responsive-ness. Conclusion △ScvO2 after VE is able to categorize VE efficiently, suggesting that it may be used as an alternative marker for fluid responsiveness in absence of invasive CI measurement.