[Predictive value of early lactate area for mortality in elderly patients with septic shock]

Objective: To investigate the predictive value of early lactate area for mortality in elderly patients with septic shock. Methods: From January 2012 to December 2013, a prospective study was conducted in the Department of Critical Care Medicine, Qilu Hospital of Shandong University. A total of 115 septic shock patients with age ≥65 years were included in the study. Serum lactate was measured every 6 hours, the lactate indicators, including early lactate area, APACHE Ⅱ score etc were recorded. Results: The overall 28-day mortality rate was 67.0%. The top three primary infection sources were lung, abdominal cavity and bloodstream. When compared to survivors, non-survivors had significantly elevated early lactate area and APACHE Ⅱ score and lowered lactate clearance[(27.4±7.6) vs ( 20.3±6.5)], they were significantly more likely to have undergone mechanical ventilation, renal replacement therapy and inotropic or vasopressor support for ≥3 d, and more frequently displayed signs of cardiovascular, respiratory, and renal and hepatic dysfunction (all P<0.05) .Receiver Operating Characteristic curves indicated the lactate area score displayed a strong predictive power for 28 day mortality as indicated by an AUC of 0.758 (P<0.01) and had significantly greater predictive power when compared to the initial lactate or lactate clearance (all P<0.05). Conclusions: In geriatric patients with septic shock, the early lactate area is a useful predictor for early death and showed better predictive value than other lactate indicators.