The Correlation Between Pv-aC0₂/Ca-v0₂ And Lactate Clearance In Patients With Septic Shock After Early Resuscitation

Objective : To investigate the relationship between Pv-aCO2/Ca-vO2 and lactate clearance rate in patients with septic shock after early resuscitation.Methods: The measurements being analyzed in this study were collected from 36 septic shock patients according to sepsis-3 which were admitted to the Emegency Intensive Care Uint（EICU） and Emergency Department（ED）in the 2nd Affiliated Hospital of Kunming Medcal University from April 2016 to May 2017.The resuscitation protocol targeted MAP、CVP、ScvO2、Pv-aCO₂/Ca-vO₂、Pv-aCO2、arterial blood lactate and lactate clearance were collected at two time points---T0（time of entrollment） and T6 （after 6 hour of fuild resuscitation）.We are analyzing the correlation of 6-LC and ScvO2、Pv-aCO2/Ca-vO2、Pv-aCO2 at T6 .Using Receiver Operation Characteristic Curve （ROCC） to identify the cutoff value of each variable in predicting 6-LC≥10%,as well as its sensitivity and specificity.36 patients were divided into two groups: 6-LC≥10% group（n=22） and 6-LC< 10% group（n=14）.ScvO2、Pv-aCO2/Ca-vO2、Pv-aCO2 were compared between two groups at two time points.Meanwhile,22 patients with nomal ScvO2 value（ScvO2 ≥ 70%） after early resuscitation were divided into 6-LC≥10% group（n=15） and 6-LC<10% group（n=7）.Pv-aCO2/Ca-vO2,Pv-aCO2 were compared between two groups at T6. We are using Receiver Operation Characteristic Curve （ROCC） to identify the cutoff value of each variable in predicting 6-LC≥10%, as well as its sensitivity and specificity in patients with nomal ScvO2.According to the prognosis at 28 days,patients were divided into two groups:survival（n=19） and death（n=17）,and compared ScvO2 , Pv-aCO2/Ca-vO2 ,Pv-aCO2 in two groups.Results: The Pv-aCO₂/Ca-vO₂ of patients with septic shock was significantly negatively correlated with lactate clearance after early resuscitation （r= -0.618, P<0.001 ）; 6-LC ≥10% group has a lower Pv-aCO2/Ca-vO2 ratio （1.34 + 0.52 vs. 1.97 +0.59; P=0.002） and lower mortality （31.8% vs 71.4%; P=0.039） than 6-LC < 10%group; The ROC analysis showed an AUC 0.843 (P < 0.001, and a Pv-aCO₂/Ca-vO₂ cut-off value of 1.325 mmHg · dL/mL O2 with sensitivity 0.864 and specificity 0.857 for lactate improvement prediction. The early recovery of patients with normal Scv02 after 6 hours, the ROC analysis showed an AUC 0.852 （P < 0.001）, and a Pv-aCO2/Ca-vO2 cut-off value of 1.495 mmHg · dL/mL O2 with sensitivity 0.933 and specificity 0.741 for lactate improvement prediction. There was no significant difference in Pv-aCO2/Ca-vO2 ratio between survival group and death group.Conclusion: The Pv-aCO2/Ca-vO2 ratio was significantly correlated with lactate clearance in patients with septic shock after early resuscitation.However, after 6 hours of resuscitation, the Pv-aCO2/Ca-vO2 ratio was not significantly different between the survival and the death..