Hyperlactatemia and altered lactate kinetics are associated with excess mortality in sepsis A multicenter retrospective observational study

Severe hyperlactatemia (> 10mmol/L) or impaired lactate metabolism are known to correlate with increased mortality. The maximum lactate concentration on day 1 of 10,724 septic patients from the eICU Collaborative Research Database was analyzed and patients were divided into three groups based on maximum lactate in the first 24 h (< 5mmol/l; >= 5mmol/l & < 10mmol/l; >= 10mmol/l). In addition, delta lactate was calculated using the following formula: (maximum lactate day 1 minus maximum lactate day 2) divided by maximum lactate day 1. A multilevel regression analysis was performed, with hospital mortality serving as the primary study end point. Significant differences in hospital mortality were found in patients with hyperlactatemia (lactate >= 10mmol/l: 79%, >= 5mmol/l & < 10mmol/l: 43%, < 5mmol/l, 13%; p < 0.001). The sensitivity of severe hyperlactatemia (>= 10mmol/l) for hospital mortality was 17%, the specificity was 99%. In patients with negative delta lactate in the first 24 h, hospital mortality was excessive (92%). In conclusion, mortality in patients with severe hyperlactatemia is very high, especially if it persists for more than 24 h. Severe hyperlactatemia, together with clinical parameters, could therefore provide a basis for setting treatment limits.