Clinical Value Of P（cv-a）CO₂/C（a-cv）O₂ In Resuscitation Of Septic Shock Patients

Objective:To explore the clinical value of central venous-arterial carbon dioxide tension difference/arterial-central venous oxygen content difference ratio[P（cv-a）CO₂/C（a-cv）O₂]in resuscitation of septic shock patients.Methods:This retrospective study included 81 patients with septic shock admitted to the emergency intensive care unit（EICU）of the Second Hospital of Hebei Medical University from January 2017 to December 2018.All patients were given early fluid resuscitation according to the requirements of the sepsis guidelines.The arterial and central venous blood gas analysis and arterial blood lactate concentration were measured before resuscitation（0h）,and at 6h,12h,24h after resuscitation.P（cv-a）CO₂/C（a-cv）O₂ was calculated before and after resuscitation.The correlation between P（cv-a）CO₂/C（a-cv）O₂ and lactate concentration and the correlation between P（cv-a）CO₂/C（a-cv）O₂ change rate and lactate clearance rate at each time point were statistically analyzed.To analyze the clinical value P（cv-a）CO₂/C（a-cv）O₂ in predicting the prognosis of septic shock patients.Result:1.P（cv-a）CO₂/C（a-cv）O₂ at 0h,6h,12h and 24h had a good correlation with blood lactate concentration（r=0.609,P<0.01;r=0.828,P<0.01;r=0.814,P<0.01;r=0.892,P<0.01）.2.The change rate of P（cv-a）CO₂/C（a-cv）O₂ and lactate clearance rate at6h,12h and 24h were well correlated（r=0.694,P<0.01;r=0.726,P<0.01;r=0.708,P<0.01）.3.P（cv-a）CO₂/C（a-cv）O₂,ScvO₂,lactate concentration,APACHEⅡand SOFA scores in ICU survivors were lower than those in deaths（P<0.05）.After24 hours of resuscitation,P（cv-a）CO₂/C（a-cv）O₂,lactate concentration,APACHEⅡand SOFA scores in ICU survivors decreased more remarkably than those in deaths,and the increase of ScvO₂ in ICU survivors was lower than that in deaths,and the difference of them were statistically significant（P<0.05）.4.At 24 hours after treatment,the receiver-operating characteristics curve showed that:area under curve（AUC）and 95%confidence interval（95%CI）were as follows:P（cv-a）CO₂/C（a-cv）O₂ ratio AUC 0.818（95%CI 0.713-0.922）;arterial blood lactate level AUC 0.887（95%CI 0.818-0.957）;the change rate of P（cv-a）CO₂/C（a-cv）O₂ AUC 0.636（95%CI 0.516-0.757）;lactate clearance rate AUC 0.815（95%CI 0.724-0.906）,the difference was statistically significant（P<0.05）.Conclusion:P（cv-a）CO₂/C（a-cv）O₂ in septic shock patients before and after fluid resuscitation therapy was correlated well with the arterial blood lactate level.The change rate of P（cv-a）CO₂/C（a-cv）O₂ in septic shock patients before and after fluid resuscitation therapy was correlated well with lactate clearance rate.P（cv-a）CO₂/C（a-cv）O₂ can be used as an indicator of tissue hypoxia and has a good practical value in the prognosis evaluation of septic shock patients.