感染性休克患者中心静脉血和混合静脉血氧饱和度缺乏一致性

目的感染性休克患者的中心静脉血氧饱和度(SCVO2)与混合静脉血氧饱和度(SVO2)的相关性分析。方法符合感染性休克诊断的25例患者分成重症肺炎组和腹腔感染组。所有患者均留置Swan-Ganz导管,从入科开始,每隔6小时不分顺序抽取中心静脉血和混合静脉血,进行血气分析,获取SCVO2和SVO2,对数据进行统计分析。结果所有患者及重症肺炎组、腹腔感染组的SCVO2和SVO2比较,差异均有统计学意义(t分别=4.90、4.29、7.21,P均<0.05),25例感染性休克患者SCVO2和SVO2的差异均值为(5.94±6.78)%,SCVO2比SVO2高,12例重症肺炎患者的SCVO2和SVO2的差异均值为(5.45±6.89)%,SCVO2比SVO2高,13例腹腔感染组患者的SCVO2和SVO2的差异均值为(7.90±6.22)%,SCVO2比SVO2高,重症肺炎组及腹腔感染组SCVO2和SVO2之间相关系数,差异有统计学意义(Δz=2.05,P<0.05)。结论感染性休克患者血流动力学不稳定时,尽量不用SCVO2替代SVO2。

Lack of equivalence between central and mixed venous oxygen saturation in patients with septic shock

Objective To analyze the correlation of central venous oxygen saturation （ScvO2） and mixed venous oxygen saturation （SvO2） in patients with septic shock. Methods A total of twenty five patients who had septic shock were recruited to study and divided into severe pneumonia group and intra-abdominal infection group; all had a Swan Ganz catheter. Then, Blood samples were drawn from central venous and pulmonary artery in random order at the beginning of being admitted to ICU and once every six hours. Data of blood samples for ScvO2 and SvO2 were analyzed. Results There were significant differences between ScvO2 and SwO2 in groups （t=4.90,4.29,7.21 ,P〈0.05）;ScvO2 was greater than SvO2 with a mean difference （ie, bias） of（5.94±6.78）% in 25 septic shock patients; ScvO2 was greater than SvO2 with a mean difference （ie, bias） of （ 5.45±6.89）% in severe pneumonia group;ScvO2 was greater than SvO2 with a mean difference （ie, bias） of （7.90±6.22）% in intra-abdominal infection group; The result （△z）of the two correlation coefficients of ScvO2 and SvO2 which were belong to severe pneumonia group and intra-abdominal infection group was 2.05 （P〈0.05）. Conclusions ScvO2 overestimated SvO2 usually when the hemodynamics of septic shock patients were instable.