Association between serum lactate levels and enteral feeding intolerance in septic patients treated with vasopressors: a retrospective cohort study

Background To assess the association between serum lactate levels and intolerance to enteral nutrition (EN) in septic patients treated with vasopressors. Methods This retrospective study was conducted between January 1, 2015 and May 1, 2018 in an intensive care unit (ICU). Patients with sepsis who were given EN and treated with vasopressors were included. EmpowerStats software and R (version 3.3.2) was used to examine the association between serum lactate levels and intolerance to EN. Results Among the 132 septic patients (age, 60.6±18.1 years) enrolled, 35 (26.5%) patients suffered intolerance to EN. Multiple logistic regression analysis demonstrated that an elevated lactate level was an independent risk factor for EN intolerance [odds ratio (OR): 2.7; 95% confidence interval (CI): 1.6-4.4; P<0.001]. The area under the receiver operating characteristic (ROC) curve for serum lactate levels was 0.764 (95% CI: 0.664-0.864). Stratified analysis suggested that age was the most prominent interactive factor for serum lactate levels in EN intolerance. Serum lactate levels were closely correlated to EN intolerance in elderly patients (age ≥65 years) (OR: 9.5; 95% CI: 2.1-42.4; P=0.0261 for interaction), while no such association was identified in younger patients (age <65 years; OR: 1.7; 95% CI: 1.0-2.9; P=0.052). Conclusions Serum lactate levels were associated with an increased risk of EN intolerance in patients with sepsis, especially in elderly individuals. An elevated serum lactate level may be an early predictor of EN intolerance in elderly septic patients treated with vasopressors. However, further studies are called for to verify these findings.