Objective: To evaluate the ability of arterial blood lactic acid concentration to predict death within 28 days of admission of patients with severe acute pancreatitis (SAP) in the intensive care unit (ICU).
Methods: Clinical data of 523 SAP patients in the MIMIC-IV database were retrospectively analyzed. Patients were divided into those who survived (n = 461) and those who died (n = 62) within 28 days of admission. The association between lactic acid concentration and all-cause death in SAP patients was determined by Cox regression analysis, Kaplan-Meier survival analysis and subgroup analysis. The ability of lactic acid concentration to predict the risk of all-cause death in SAP patients was determined by time-dependent receiver operating curve (ROC) analysis.
Results: Arterial blood lactic acid concentration was significantly higher in the 62 patients who died within 28 days than in the 461 patients who survived (P < 0.05). Adjusted multivariate Cox regression analysis showed that lactic acid concentration was a significant independent predictor on all-cause mortality within 28 days of admission for SAP (hazard ratio = 1.22, 95% confidence interval 1.09-1.36, P < 0.001), as did time-dependent ROC analysis (area under the ROC curve = 0.741). Kaplan-Meier analysis showed that the rate of all-cause mortality within 28 days of admission was significantly higher in patients with high than low lactic acid concentration (P < 0.0001). Subgroup analysis showed that there was no significant interaction between lactic acid concentration and other factors with all-cause death within 28 days of admission (all P > 0.05).
Conclusion: Arterial blood lactic acid concentration is an important independent predictor of all-cause mortality within 28 days of admission of SAP patients in the ICU.
Keywords: 28 days; Lactic acid; acute severe pancreatitis; intensive care unit; prognosis.