The Value Of StO₂ And RincStO₂ On The Early Recognition Of Septic Shock

Objective:To quantify sepsis-induced alterations in muscle tissue oxygenation saturation?StO₂?using near infrared reflectance spectroscopy?NIRS?,and to explore the value of the changes in StO₂ after vascular occlusion test on the early recognition of septic shock.Methods:From July 2018 to June 2019,acute infection patients in the emergency department of the First Affiliated Hospital of China Medical University were enrolled prospectively.Patients were assigned into septic group and control group according to the SOFA score.Then septic group was further assigned into the septic patients with and without shock.Through vascular occlusion test?VOT?,thenar eminence StO₂ was measured continuously by NIRS before?StO₂ baseline?,during,and after the three-minute occlusion of the brachial artery using a cuff inflated 50 mmHg above systolic arterial pressure.The changes in StO₂ were record by the slope of increase in StO₂?RincStO₂?during the first 15s after the three-minute occlusion and by the difference of StO₂??StO₂?between the end of the first minute of reperfusion and StO₂ baseline.The differences of StO₂,RincStO₂ and?StO₂ between septic group and control group,the septic patients with and without shock were analyzed.Results:During the study period,two hundred and thirty-six infected patients were enrolled,including 98 in septic group and 138 in control group.Hemoglobin?HGB??t=3.983?and temperature?T??t=5.205?were influence factor of StO₂?R2=0.377,p<0.01?,but lactate?Lac?was not?t=-1.418,p=0.159?.RincStO₂ has no linear correlation with HGB,T,Lac and SOFA score?F=0.589 P>0.05?.The StO₂ baseline was lower in septic group than in control group?75.31±4.24%vs 81.23±3.10%,P<0.05?.RincStO₂ was significantly lower in septic group than in control group?1.90±0.31%/s,2.81±0.35%/s,P<0.05?,and the septic patients with shock was even lower than without shock?1.68±0.33%/s vs1.99±0.26%/s,p<0.05?.A ROC curve showed that the slope was a good predictor of septic shock?AUC:0.76,p<0.05?.A slope of 1.845%/s represented the best cut-off value,with a sensitivity of 72.7%and a specificity of 68.4%.And another ROC curve showed that StO₂ was not a good predictor of septic shock?AUC:0.63,p>0.05?.The StO₂ of77.50%represented the best cut-off value,with a sensitivity of 36.4%and a specificity of94.7%.?StO₂ was also lower in septic group than in control group?9.28±2.31%/s vs13.16±4.34%/s,p<0.05?,but there was no statistical discrepancy between septic patients with and without shock?8.58±2.14%/s,9.53±2.32%/s,p>0.05?.Conclusion:In the early stage of sepsis,StO₂ and RincStO₂ after vascular occlusion test can predict the occurrence of septic shock,and RincSt O₂ is better than StO₂.