Association between acute gastrointestinal injury and biomarkers of intestinal barrier function in critically ill patients

BACKGROUND: To assess the associations of biomarkers of intestinal barrier function and other clinical variables with acute gastrointestinal injury (AGI) grade, and of these clinical variables with mortality in critically ill patients. METHODS: This was a single-center, observational, prospective study. Patients were included if they were diagnosed with AGI and underwent tests for the measurement of plasma levels of intestinal fatty acid–binding protein (i-FABP), d-lactate (d-la), and lipopolysaccharide. General characteristics, AGI grades, Acute Physiology and Chronic Health Evaluation (APACHE) II scores, Sepsis-related Organ Failure Assessment (SOFA) scores, intra-abdominal pressure (IAP), and 28-day mortality were recorded and compared among patients with different AGI grades. RESULTS: Among the 90 included patients, the APACHE II score, IAP, and LPS and D-la levels significantly differed between the four AGI grades. Multinomial logistic regression analysis with grade I as the reference for grades II, III, and IV revealed that high APACHE II scores increased the odds of AGI grade III (odds ratio [OR], 1.754; 95% confidence interval [CI], 1.225–2.511) and grade IV (OR, 1.493; 95% CI, 1.079–2.066). Similarly, IAP increased the odds of AGI grade III (OR, 1.622; 95% CI, 1.111–2.369) and grade IV (OR, 1.518; 95% CI, 1.066–2.162). Elevated D-la increased the odds of AGI grades II (OR, 1.059; 95% CI, 1.005–1.117), III (OR, 1.155; 95% CI, 1.052–2.268), and IV (OR, 1.088; 95% CI, 1.013–1.168). In contrast, i-FABP and LPS did not increase the odds of any AGI grade. SOFA scores could independently predict the odds of death in AGI patients (OR, 1.223; 95% CI, 1.007–1.485). CONCLUSION: AGI patients exhibit loss of gastrointestinal barrier function, and d-la could serve as a better marker of AGI grade than i-FABP or lipopolysaccharide.