The Effect Of Low Lactate Level In Early Stage On Diagnosis,Treatment,and Prognosis Of Sepsis Patients

Objective: It has been proved that hyperlactatemia is an independent predictor of mortality in patients with sepsis.But there exist clinical cases of patients diagnosed with sepsis or septic shock who do not have elevated lactate in the early stage despite clinical deterioration.Our purpose was to investigate the effect of low lactate level in early stage on diagnosis,treatment,and prognosis of patients in sepsis and septic shock.Methods: We conducted a retrospective observational study involving 830 adult sepsis patients admitted to Intensive Care Unit(ICU),baseline data and various clinical data within 24 hours after admission to ICU of enrolled patients were collected.We calculated time-weighted lactate(Lac TW),a dynamic value that incorporate both the magnitude of change and the time interval of such change,to represent lactate levels in the first 24 hours.Logistic regression was used to analyze the predictors of mortality in sepsis patients and the influencing factors of time-weighted lactate level.Receiver Operating Characteristic Curve(ROC curve)was used to find the cutoff of Lac TW for predicting mortality,and the influencing factors for mortality in the low lactate group were further studied.The primary outcome was hospital mortality.Results: A total of 830 patients were enrolled and divided into a survival group(412/830)and a death group(418/830),and a low lactate group(394/830)and a high lactate group(436/830)according to the lactate level during 24 hours after admission to ICU).Lac TW > 1.975mmo/L was found to be the cut-off threshold for predicting mortality(Area Under Curve(AUC)= 0.646,P < 0.001).Logistic regression analysis showed that time-weighted lactate was affected by the following indicators: acute physiology and chronic health evaluation Ⅱ(APACHE Ⅱ)score(P < 0.001),activated partial thromboplastin time(APTT)(P = 0.002),total bilirubin(P = 0.012),creatinine(P = 0.037),with hypotension(P < 0.001),chronic kidney disease(P = 0.013)and required continuous renal replacement therapy(CRRT)(P < 0.001).Of the 394 patients in the low lactate group,Age(P = 0.002),malignancy(P < 0.001),lactate dehydrogenase(P = 0.006),required treatment such as Mechanical ventilation(P <0.001),CRRT(P < 0.001),vasoactive drugs(P < 0.001)and glucocorticoids(P <0.001),and failure to reach the target fluid resuscitation of 30ml/kg within 6 hours(P =0.003)were independently associated with hospital mortality.Conclusions: Mortality in patients with non-elevated lactate levels was associated with age,complicated malignancy,the need for special supportive treatment,such as vasoactive drugs,glucocorticoids and CRRT,etc.,and the mortality rate of the low-lactate group was also correlated with whether the target amount of fluid resuscitation within 6 hours.Patients in the low lactate group were less likely to have organ dysfunction,lactate levels did not increase or delayed in some septic shock patients in the early stage,leading to delayed diagnosis and neglect of enhanced treatment measures by clinicians,which further affected the timeliness and adequacy of diagnosis and treatment,and ultimately affected the prognosis.