ABSTRACT
BACKGROUND: Sepsis, characterized by dysregulated host responses to infection, remains a critical global health concern, with high morbidity and mortality rates. The gastrointestinal tract assumes a pivotal role in sepsis due to its dual functionality as a protective barrier against injurious agents and as a regulator of motility. Dexmedetomidine, an α2-adrenergic agonist commonly employed in critical care settings, exhibits promise in influencing the maintenance of intestinal barrier integrity during sepsis. However, its impact on intestinal motility, a crucial component of intestinal function, remains incompletely understood. METHODS: In this study, we investigated dexmedetomidine's multifaceted effects on intestinal barrier function and motility during sepsis using both in vitro and in vivo models. Sepsis was induced in Sprague-Dawley rats via cecal ligation and puncture. Rats were treated with dexmedetomidine post-cecal ligation and puncture, and various parameters were assessed to elucidate dexmedetomidine's impact. RESULTS: Our findings revealed a dichotomous influence of dexmedetomidine on intestinal physiology. In septic rats, dexmedetomidine administration resulted in improved intestinal barrier integrity, as evidenced by reduced mucosal hyper-permeability and morphological alterations. However, a contrasting effect was observed on intestinal motility, as dexmedetomidine treatment inhibited both the frequency and amplitude of contractions in isolated intestinal strips and decreased the distance of ink migration in vivo. Additionally, dexmedetomidine suppressed the secretion of pro-motility hormones while having no influence on hormones that inhibit intestinal peristalsis. CONCLUSION: The study revealed that during sepsis, dexmedetomidine exhibited protective effects on barrier integrity, although concurrently it hindered intestinal motility, partly attributed to its modulation of pro-motility hormone secretion. These findings underscore the necessity of a comprehensive understanding of dexmedetomidine's impact on multiple facets of gastrointestinal physiology in sepsis management, offering potential implications for therapeutic strategies and patient care.
ABSTRACT
OBJECTIVE: Improvement of mucosal barrier function and reduction of bacterial translocation are important in the management of sepsis. The mechanisms that underlie the protective effects of colloids on the intestinal mucosal barrier are unclear. The study aims to investigate the effect of fluid resuscitation with hydroxyethyl starch (HES) 130/0.4 against intestinal mucosal barrier dysfunction in a rabbit model of sepsis. MATERIALS AND METHODS: Thirty healthy rabbits were randomly and equally divided into a sham-operated control, a sepsis model, or a sepsis + HES treatment group. The sepsis model and sepsis + HES treatment groups were subjected to a modified colon ascendens stent peritonitis (CASP) procedure to induce sepsis. Four hours after the CASP procedure, fluid resuscitation was performed with 6% HES 130/0.4. Arterial and superior mesenteric vein blood samples were collected 4 and 8 h after the CASP procedure for blood gas analysis and measuring tumor necrosis factor-α, interleukin-10, and D-lactate levels. The rabbits were euthanized 8 h after CASP, and sections of the small intestine were stained to evaluate histopathological changes. RESULTS: Respiratory rate and blood pressure were stable during the resuscitation period. Fluid resuscitation with 6% HES 130/0.4 alleviated pathological changes in the abdominal cavity, improved blood gas parameters and inflammatory mediator levels, decreased plasma D-lactate levels, and reduced intestinal mucosal injury compared with the non-treated sepsis model. CONCLUSIONS: Fluid resuscitation with 6% HES 130/0.4 protects against intestinal mucosal barrier dysfunction in rabbits with sepsis, possibly via mechanisms associated with improving intestinal oxygen metabolism and reducing the release of inflammatory mediators.
