Analysis of Pathogenic Bacteria and Associated Risk Factors of Bloodstream Infections in ICU Patients Undergoing ECMO Support Using mNGS Technology

Abstract

Objective: To analyze the characteristics of pathogens and related risk factors of bloodstream infections (BSI) in patients undergoing ECMO support using mNGS technology. Methods: A retrospective analysis was conducted on 59 patients who received ECMO support in the Emergency Intensive Care Unit (EICU) of the Affiliated Hospital of Xuzhou Medical University from January 2021 to March 2024. The patients were divided into two groups based on the presence of BSI: the infection group (BSI group) and the noninfection group (N-BSI group). The clinical data of the two groups were compared, and the characteristics of pathogens were analyzed using mNGS technology. Logistic regression was used to analyze the related risk factors for BSI associated with ECMO. Results: (1) The incidence of BSI in patients undergoing ECMO support was 20.34%. Compared to the N-BSI group, the BSI group had significantly higher levels of procalcitonin (14.9 ± 7.2 vs. 9.4 ± 4.7), C-reactive protein (140.58 ± 24.64 vs. 87.26 ± 11.06), blood lactate (8.55 ± 1.40 vs. 5.07 ± 0.55), and ECMO catheter indwelling time (12.00 ± 1.71 vs. 7.96 ± 0.76) (p < 0.05). (2) mNGS detection indicated that the BSI group mainly identified viruses and Gram-negative bacilli (G-), with Acinetobacter baumannii being the most prevalent pathogen. The resistance genes were predominantly blaTEM, which confers resistance to penicillins and cephalosporins. (3) Logistic regression analysis revealed that diabetes, ECMO indwelling time, blood lactate levels, and G-bacilli infection were risk factors for BSI during ECMO. Conclusion: Gram-negative bacteria are the primary pathogens in BSI among patients undergoing ECMO support. Diabetes, ECMO catheter indwelling time, and elevated blood lactate are independent risk factors for these infections. Rational selection of antibiotics and strengthened management of related factors can effectively control the occurrence of BSI during ECMO support.