Anastomotic leak occurs independently from microbiota shifts associated with surgical bowel preparation

Abstract

Abstract Background Following bowel surgery, microbially driven complications, including anastomotic leak (AL) and surgical site infections (SSI), remain major sources of morbidity and mortality. For more than 50 years, bowel preparation has been administered with the assumption that gut decontamination serves to reduce post-surgical complications. Here, we test this hypothesis in a murine model of colon surgery fed either regular chow or a high-fat, high-sugar Western diet. Mice then received one of four interventions the day before colon surgery: water (control), mechanical bowel preparation (MBP), oral antibiotics (OA), or both MBP and OA. Mice were subsequently assessed for AL and wound healing. Results Despite predicted changes in the microbiome, no differences in the rates of AL or wound breakdown were observed. Changes in fecal short-chain fatty acids were noted but did not reflect specific effects of treatment or AL; however, fecal IgA was greater in mice fed WD and among those who had AL (P = 0.007). RNAseq analysis of transcript abundances similarly did not reveal significant mechanistic pathways associated with AL. Conclusions While we did identify bacterial genera that may be causally associated with AL and could be used to develop a predictive index, future work is required to elucidate specific mechanistic pathways driving AL.