Serial absolute lactate value < 4 versus relative 10% reduction as a predictor of mortality in severe sepsis and septic shock

Introduction Serial lactate measurements provide a valuable tool to risk-stratify patients, determine the presence of ongoing tissue hypoperfusion, and potentially evaluate efficacy of therapeutic interventions. Prior studies have shown lactate clearance to be a valuable predictor of patient outcomes, however some have defined adequate change in lactate by a decrease from baseline by 10% whereas others considered an absolute reduction to lactate < 4mmol/L. We hypothesize that a serial absolute lactate < 4mmol/L after initial resuscitation will be as effective a predictor of future mortality as a change by 10%.