Effect of Low-Dose Dexmedetomidine on Intestinal Barrier and Functional Recovery in Elderly Patients Undergoing Orthopedic Surgery for Lower Limbs

Abstract

Objective: This study used the minimum recommended clinical dose of dexmedetomidine to investigate whether it can protect the intestinal barrier and the effects on intestinal function recovery in elderly patients undergoing lower limb orthopedic surgery. Methods: 56 patients, who underwent elective lower limb orthopedic surgery in our hospital from November 1, 2019 to November 1, 2021, were divided into control group (saline group) and DEX group (dexmedetomidine group) by random numbers method. The DEX group received dexmedetomidine at 0.5 μg/kg, pumped within 15 min and then maintained at 0.1 μg/kg/h until 30 min before the skin suture. The control group performed the same procedure with normal saline instead. The primary outcomes included the time of first hepatic gate exhaust, serum diamine oxidase, and D-lactate levels. Secondary outcomes include total amount of sufentanil, mean arterial pressure, heart rate, duration of anesthesia, duration of surgery, tumor necrosis factor- α, C-reactive protein, lipopolysaccharide levels. Results: The time of first anal exhaust in the DEX group was significantly shorter compared with the control group (13.23 ± 4.98 hours vs19.67±5.16 hours; p<0.001), and the total amount of sufentanyl in the DEX group was significantly lower than that in the control group (35.32±10.23ug vs 42.33±12.19ug; p=0.002). At 24 hours after surgery, serum diamine oxidase, tumor necrosis factor-α, and C-reactive protein levels increased in both groups, but no difference was statistically significant (p>0.05), and there was no significant difference in LPS levels in the two groups before and 24 hours after surgery (p>0.05). D-lactate was increased in both groups at 24 hours after surgery, but the D-lactate increased more in control patients than in the DEX group (36.17±14.69 mg/L vs 29.10±12.19 mg/L;p=0.017). Correlation analysis showed that diamine oxidase, D lactate, age, APACHE II score, total amount, and time to first anal discharge in the DEX group (p<0.05). Conclusion: The intraoperative administration of dexmedetomidine can accelerate the recovery of gastrointestinal function, which may be related to the protective effect of DEx on the gastrointestinal barrier.