Prognostic Value Of Early Lactate Dynamic Monitoring In Septic Shock Patients Associated With Bloodstream Infection

Objective Lactate is a physiological marker of tissue perfusion,stress state and glucose metabolism in patients with sepsis and septic shock,while bloodstream infection is one of the infection types with the highest mortality rate in ICU(Intensive Care Unit).The purpose of this study was to analyze the prognostic value of lactate dynamic level during early resuscitation in septic shock patients associated with bloodstream infection as defined by SEPSIS 3.0,and to explore the best prognostic value.MethodsA total of 42 patients with septic shock related to bloodstream infection admitted at our department from November 2013 to November 2019 were retrospectively studied.The patients were divided into survival group and death group according to 28-day clinical outcome.All patients received the sepsis bundle strategies recommended by the guidelines.The relevant characteristic data(age,gender,types of microorganisms in blood culture,sources of blood stream infection),the related organ indexes(total bilirubin,serum creatinine,total urine output within 12 hours after resuscitation)that affected lactate metabolism,the severity indexes of patients(APACHE Ⅱ [ Acute Physiology and Chronic Health Evaluation Scoring System Ⅱ ],SOFA [ Sequential Organ Failure Assessment],NEmax[the highest dose of norepinephrine within 12 hours after resuscitation])of all patients were collected.The arterial lactate levels(LacH0,LacH6,LacH12)were measured at 0,6 and 12 hours after resuscitation began and the lactate clearance rates(LacClear H6,LacClear H12)were calculated at 6-hour and 12-hour.The measurement data used the t test and the Mann-Whitney U test,and chi-square test was used in the count data.The statistical difference of the related data between the two groups was compared to explore the correlation between the lactate variables and the prognosis.By drawing the receiver operating characteristic curve(ROC curve)of each lactate variables,the best lactate variable related to prognosis obtained through the area under the ROC curve.Results1.There were no statistical differences in the average age,gender,types of microorganisms in blood culture,sources of blood stream infection between two groups.There were no significant differences in total bilirubin and creatinine levels between two groups of patients in the early stage of resuscitation,but the 12-hour cumulative urine output of the death group was significantly less than that in the survival group(P<0.05).The APACHE Ⅱ score,SOFA score and NEmax,which reflect the severity of the disease,were significantly higher in the death group than in the survival group(P≤0.01).2.LacH0,LacH6,and LacH12 in the death group were higher than those in the survival group,and there were statistical differences(P<0.05);LacClear H6 and LacClear H12 in the survival group were significantly higher than those in the death group(P<0.05).3.By drawing the ROC curve,the optimal cut-off values of LacH0,LacH6 and LacH12 were 5.21 mmol/L,4.73 mmol/L and 3.30 mmol/L,and the optimal cut-off values of LacClear H6 and LacClear H12 were 0.13 and 0.21,respectively.The lactate variable with the largest AUC was LacH12(0.87),and it was statistically different from the AUC of LacClear H6 and LacClear H12(P<0.05).Conclusions1.Values of lactate and lactate clearance rate in early stage of resuscitation have good prognostic value for patients with septic shock caused by bloodstream infection in the ICU.2.For patients with septic shock caused by bloodstream infection in the ICU,the absolute values of lactate in the early stage of resuscitation are more closely related to the prognosis than the lactate clearance rates.The lactate value at 12 hours after resuscitation begin may be the best prognostic variable.The lactate value is still higher than 3.3mmol/L at 12-hour after resuscitation begin,which is more closely associated with poor prognosis than other lactate variables.