Assessing the Prognostic Significance of Lactate Levels and Arterial Base Excess in Patients After Pancreatic Surgery: A Retrospective Analysis

Abstract

Background: Despite advances in surgical approaches and various treatment regimens, postoperative mortality after pancreatic surgery remains high (3.8%). Lactate levels and base excess show metabolic changes in the body and are useful prognostic markers of in-hospital mortality.Objective: To evaluate the prognostic significance of lactate levels and arterial base excess in patients after pancreatic surgery. Materials and methods: We retrospectively analyzed a database of patients who underwent pancreatic surgery (n=134) between 2019 and 2023. The patients were grouped: group 1 (n=11) for the patients who died in the hospital in the postoperative period and group 2 (n=123) for the patients discharged from the hospital.Results: In group 1, the lactate level at the time of admission was significantly higher than in group 2: 5.61 (2.51-11.13) mmol/L and 1.84 (1.33-2.98) mmol/L, respectively, P<.001. Changes of this parameter on day 1: 3.60 (2.41-4.24) mmol/L in group 1 and 2.27 (1.72-3.64) in group 2, P<.001. On day 2: 2.55 (1.43-3.54) mmol/L in group 1 and 1.40 (1.16-1.92) mmol/L in group 2, P=.001. On day 3: 1.85 (1.57-2.91) mmol/L in group 1 and 1.24 (1.14-1.54) mmol/L in group 2, P=.002. The base excess was also higher in group 1 compared with group 2: −7.50 (−10.75-(−5.40)) mmol/L and −4.00 (−5.30-(−2.35)) mmol/L, respectively, P=.001. Changes of this parameter on day 1: −5.20 (−6.90-(−1.40)) mmol/L in group 1 and −2.70 (−4.00-(−0.80)) in group 2, P=.002. On day 2: −1.90 (−7.00- (−1.40)) mmol/L in group 1 and 1.62 (−0.80-3.50) mmol/L in group 2, P=.006. On day 3: −1.25 (−8.00-2.3) mmol/L in group 1 and 2.55 (0.80-3.80) mmol/L in group 2, P=.027. The area under the receiver operating characteristic curve (AUROC) for relationship between lactate level and death was 0.833, 95% CI: 0.704-0.962, P<.001. The cutoff point value was 2.5 mmol/L, whereas sensitivity and specificity were 81.8% and 69.1%, respectively. The AUROC for relationship between base excess and death was 0.801, 95% CI: 0.657-0.945, P=.001. The cutoff point value was −6.6 mmol/L, whereas sensitivity and specificity were 72.7% and 84.6%, respectively. When comparing the AUROC values, we found no significant differences (P=.520). Conclusions: Arterial blood lactate and base excess are equally good at predicting in-hospital mortality in patients undergoing pancreatic surgery.