Clinical impact of lactate on postoperative pancreatic fistula after pancreaticoduodenectomy: A single-center retrospective study of 1,043 patients.

BACKGROUND/OBJECTIVES: Several hemodynamic markers have been studied to predict postoperative complication which is a risk factor for poor quality of life and prognosis. The aim of this study was to determine whether postoperative lactate clearance could affect clinical outcome based on complications in one surgical patient group. METHODS: We retrospectively reviewed data from all patients who underwent pancreaticoduodenectomy (PD) at Samsung Medical Center from January 2015 to December 2019. Differences in baseline characteristics of patients, intraoperative outcome, and postoperative outcome were evaluated according to the presence or absence of clinically relevant postoperative pancreatic fistula (CR-POPF). RESULTS: Among a total of 1107 patients, 1043 patients were tested for arterial lactate levels immediately after surgery, and the day after surgery. Immediately postoperative hyperlactatemia (lactate ≥2.0 mmol/L) was not related to CR-POPF (P = 0.269). However, immediately postoperative hyperlactatemia with a negative lactic clearance on postoperative day (POD) 1 was related to CR-POPF (P = 0.003). In multivariate analyses, non-pancreatic cancer (hazard ratio (HR): 2.545, P < 0.001), soft pancreatic texture (HR: 1.884, P < 0.001), and postoperative hyperlactatemia with negative lactate clearance on POD 1 (HR: 1.805, P = 0.008) were independent risk factors for CR-POPF. CONCLUSIONS: Hyperlactatemia with negative lactate clearance after PD, one of the high-risk surgeries requiring postoperative ICU care, is a risk factor for CR-POPF. In case of immediately postoperative hyperlactatemia after PD, lactate clearance with serial lactate level follow-up can be used for achieving the hemodynamic goal to prevent CR-POPF.

Base excess is superior to lactate-levels in prediction of ICU mortality after cardiac surgery.

INTRODUCTION: Cardiac surgery with the use of cardiopulmonary bypass is known to induce distinct metabolic changes. Respective changes in acid-base status including increased systemic lactate levels were previously related to clinical outcomes, but data remain controversial. Therefore, we aim to investigate the relevance of lactate and base excess (BE) levels on ICU-mortality in patients admitted to the ICU after cardiac surgery. MATERIALS AND METHODS: Perioperative data of patients treated in a tertiary care academic center admitted to the ICU after on-pump surgery were analyzed in a retrospective fashion. Receiver operation characteristic (ROC) curves were constructed for admission lactate-levels and BE with calculation of optimal cut-off values to predict ICU mortality. Univariate followed by multivariate regression models were constructed to identify potential outcome-relevant indices. RESULTS: Data from 1,058 patients were included in the analysis. Area under the curves for prediction of ICU mortality were 0.79 for lactate levels at ICU admission (sensitivity 61.9%/ specificity 87.5%; optimal cut-off level 3.9mmol/l), and 0.7 for BE (sensitivity 52.4%/ specificity 93.8%, optimal cut-off level -6.7), respectively. Multivariate regression identified BE < -6.7 as the single metabolic predictor of ICU-mortality (HR 4.78, 95%-CI 1.4-16.33, p = 0.01). Explorative subgroup analyses revealed that the combination of lactate ≤3.9mmol/l and BE ≤ -6.7 has stronger impact on mortality than a combination of lactate of >3.9mmol/l and BE > -6.7 (HR 2.56, 95%-CI 0.18-37.17). CONCLUSIONS: At ICU-admission, severely reduced BE appears superior to hyperlactatemia with regard to prediction of ICU-mortality in patients after cardiac surgery.