Effect of dexmedetomidine on recovery of postoperative gastrointestinal function in patients with adhesive bowel obstruction: a single-center randomized clinical trial

This study aimed to explore the effect of dexmedetomidine (Dex)-based anesthesia on postoperative gastrointestinal (GI) function in patients with acute adhesive bowel obstruction (ABO) who underwent enterectomy through the inhibition of intestinal inflammatory and oxidative responses. A total of 150 participants with acute ABO were enrolled receiving a loading dose of 0.5 µg·kg− 1 Dex over 15 min followed by a maintenance dose of 0.3 µg· kg− 1· h− 1 (Dex group) until 30 min before the end of surgery or placebo (normal saline) infusion (Con group). The primary outcome was the time to first flatus. The secondary outcomes were postoperative GI function measured by the I-FEED scoring system, time to first oral feeding and first feces, the indicators related to intestinal mucosal permeability, inflammation, and oxidative stress, MAP, HR, anesthetics consumption, incidence of postoperative nausea and vomiting (PONV), and the length of hospital stay. A total of 133 patients (67 in the Dex group and 66 in the Con group) were included in the analysis. Compared with the Con group, the Dex group demonstrated significantly shorter time to first flatus [61 (15) h vs. 73 (17) h; mean (SD); P < 0.001], time to first feces [85 (15) h vs. 95 (20) h; P < 0.001], and postoperative hospital stay [10 (2) days vs. 11 (2) days; P = 0.002]. The Dex group also had significantly lower I-FEED scores from postoperative day (POD) 1 to POD6 (all P < 0.05). Furthermore, the Dex group exhibited lower plasma levels of indicators associated with intestinal mucosal permeability (lipopolysaccharide and intestinal fatty acid binding protein 2), inflammation (interleukin-6 and tumor necrosis factor-α), and oxidative stress (malondialdehyde), along with higher levels of superoxide dismutase. Intraoperative consumption of propofol [4.41 (1.12) mg·kg⁻¹·h⁻¹ vs. 5.25 (1.31) mg·kg⁻¹·h⁻¹; mean (SD); P < 0.0001] and remifentanil [8.88 (7.45, 10.75) µg·kg⁻¹·h⁻¹ vs. 9.80 (8.25, 12.45) µg·kg⁻¹·h⁻¹; median (IQR); P = 0.025], as well as postoperative consumption of sufentanil [2.08 (2.07, 2.11) µg·kg⁻¹ vs. 2.24 (2.15, 2.33) µg·kg⁻¹; median (IQR); P < 0.0001], were significantly lower in the Dex group. Intraoperative administration of Dex may be a viable strategy for promoting postoperative recovery of GI function in patients with acute ABO undergoing enterectomy. The mechanism is potentially associated with inhibition of inflammatory and oxidative responses, thereby protecting the intestinal barrier against injury.