Risk Factors for Mortality in Sepsis Patients without Lactate Levels Increasing Early

Abstract

Objectives. Our purpose was to investigate the influencing factors for mortality in sepsis patients without lactate levels increasing in the early stage. Methods. We conducted a retrospective observational study involving 830 adult sepsis patients admitted to ICU. We calculated time-weighted lactate (LacTW), a dynamic value that incorporates both the magnitude of change and the time interval of such change, to represent lactate levels in the first 24 hours. ROC curve was used to find the cutoff of LacTW for predicting mortality, and the influencing factors for lactate levels and mortality in the low lactate group were further studied. The primary outcome was hospital mortality. Results. Among 830 patients, LacTW > 1.975 mmo/L was found to be the cutoff threshold for predicting mortality (AUC = 0.646, $P$  < 0.001). The following indexes related to organ dysfunction influenced LacTW: 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 glucocorticoid ( $P$  < 0.001), and failure to reach the target fluid resuscitation of 30 ml/kg within 6 hours ( $P$  = 0.003) were independently associated with hospital mortality. Conclusions. Due to the lower incidence of early organ dysfunction, lactate levels are not increased or delayed in some septic shock patients in the early stage, thus affecting the alertness of clinicians and the timeliness and adequacy of fluid resuscitation, and finally affects the prognosis.