Background

Acute gastrointestinal injury (AGI) after cardiopulmonary bypass (CPB) is associated with poor prognosis. This study aimed to evaluate the effect of preoperative probiotic supplementation on the incidence of AGI in patients undergoing CPB procedure.

Methods

This was a double-blind, randomized controlled trial conducted in a single center. The patients undergoing HVR with CPB between September 2022 and February 2023 were randomly assigned to receive either probiotic (Lac group) or placebo (Placebo group). The probiotic was administered daily for seven days prior to surgery.Univariate and multivariate logistic regression analysis was performed to identify independent risk factors for AGI. A P-value < 0.05 was considered statistically significant. Gut microbiota composition was assessed using 16 s rRNA analysis.

Results

A total of 52 patients were randomly assigned to two groups (26 in the Lac group, 26 in the Placebo group). Patients were followed for at least 30 days after surgery. During the follow-up period, 15 of the 52 patients (28.85%) developed AGI. The incidence of AGI was significantly lower in the Lac group (15.38%) compared to the Placebo group (42.31%), with a difference of 26.93% (P = 0.032). Moreover, patients in the Lac group had a significantly shorter ICU stay (6 [5, 36] vs. 5 [4, 5.5] days, P = 0.041) and a lower incidence of nosocomial infections (11.54% vs. 34.62%, P = 0.048). Multivariate analysis identified a higher Cardiac Surgery Score (CASUS) and CPB duration ≥ 132 min as independent risk factors for AGI, whereas probiotic supplementation was the only protective factor. Furthermore, 16S rRNA sequencing revealed significant differences in gut microbiota composition between the Lac and Placebo groups.

Conclusions

Preoperative probiotic supplementation may be an effective strategy to reduce the incidence of AGI and AGI-related complications in CPB patients. These findings suggest that probiotics could be considered a preventive intervention for AGI in this patient population.