Effect of Dexmedetomidine on Intestinal Barrier in Patients Undergoing Gastrointestinal Surgery-A Single-Center Randomized Clinical Trial.

INTRODUCTION: Gastrointestinal failure results in death in critically ill patients. This study aimed to explore the effect of dexmedetomidine (DEX) on intestinal barrier function and its mechanism in critically ill patients undergoing gastrointestinal surgery. METHODS: Patients undergoing gastrointestinal surgery were randomized into the DEX group (n = 21) or midazolam (MID) group (n = 21). Sufentanil was used for analgesia in both groups. In the DEX group, DEX was loaded (1 µg/kg) before sedation and infused (0.7 µg/kg/h) during sedation. In the MID group, MID was loaded (0.05 mg/kg) before sedation and infused (0.1 mg/kg/h) during sedation. The mean arterial pressure , heart rate , borborygmus resumption time , first defecation time, length of intensive care unit stay, and length of hospital stay were observed. The diamine oxidase (DAO), D-lactate , TNF-α, IL-6, and α7nAChR levels in plasma or hemocytes were detected before the start of sedation (0 h) and after sedation (24 h). RESULTS: No significant differences in age, sex, body mass index, Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores were noted (P > 0.05). The mean arterial pressure between 0 h and 24 h showed no significant difference between the groups (P > 0.05), but the heart rate was significantly lower in the DEX group (P = 0.042). The borborygmus resumption time was significantly earlier in the DEX group (P = 0.034). The lengths of intensive care unit stay (P = 0.016) and hospital stay (P = 0.031) were significantly shorter in the DEX group. The TNF-α level in the DEX group was lower at 24 h than 0 h. The D-lactate level was significantly lower in the DEX group than the MID group at 24 h (P = 0.016). The expression of α7nAChR in the DEX group was significantly higher at 24 h than 0 h (P < 0.05). CONCLUSIONS: DEX maintained intestinal barrier integrity in patients undergoing gastrointestinal surgery through the cholinergic anti-inflammatory pathway.