Lactate: prognostic biomarker in severely burned patients

Plasma lactate (PL) has been used as a marker of cellular hypoxia and shock. The correlation between PL and clinical outcome has been well accepted in hemorrhagic and septic shock. In contrast to the existing evidence, there are no or almost no data dealing with lactate and burn-related outcome. We attempted to assess whether early plasma lactate (PL) is a useful parameter to predict outcome in burned patients. A prospective study was conducted in a 20-bed adult burn ICU at a university-affiliated teaching hospital in Tunis. Patients admitted within the first 24h post burn with greater than 10% total body surface area (TBSA) burned were enrolled in the study. There were 60 males and 20 females. Mean age was 40.7 ± 19.5 years old, and average TBSA was 32 ± 21%. At admission, 86.7% patients had an initial lactate value of more than 2 mmol/L. In our study, an initial lactate value of 4 mmol/L provided the best sensitivity and specificity: 88% and 79% respectively for predicting sepsis, with an area under the ROC curve of 0,82. Furthermore, plasma lactate cut-off value for mortality prediction was 4.46 mmol/l with a good sensitivity (86%) and specificity (92%). Mortality rate was 36.25%. Plasma lactate appears to be a powerful predictor biomarker of sepsis and mortality in burn patients.