Dexmedetomidine (DEX) is beneficial for postoperative intestinal barrier function in patients who have gastrointestinal (GI) surgery, according to a study in the Journal of Surgical Research.
The randomized, double-blinded, prospective, controlled study enrolled patients who were admitted to the intensive care unit after elective GI surgery, received mechanical ventilation via intubation through the oral trachea with an estimated ventilation time of over 24 hours, and required analgesia and sedation.
The study participants were randomly assigned to receive DEX or midazolam (MID). DEX was loaded (1 μg/kg) before sedation and was infused (0.7 μg/kg/h) during sedation. MID was loaded (0.05 mg/kg) before sedation and infused (0.1 mg/kg/h) during sedation.
The primary outcomes included levels of D-lactate (D-LAC), diamine oxidase (DAO), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and α7-nicotinic acetylcholine receptor (α7nAChR) in plasma or hemocytes.
A total of 42 patients were included in the study — 21 in the DEX group (mean age, 69.19±8.52 years; 16 men) and 21 in the MID group (mean age, 69.38±9.18 years; 16 men). The study participants received parenteral nutrition within the first 24 hours postoperation, with energy of 20 to 25 kcal/kg. Antibiotics included ceftazidim and metronidazole.
The TNF-α level was lower in the DEX group at 24 hours vs 0 hours, but the IL-6 level did not change significantly. TNF-α and IL-6 levels did not change significantly from 0 hours to 24 hours in the MID group. No significant difference was observed in TNF-α or IL-6 in the DEX and MID groups at 0 hours (P >.05). The DEX group had decreased production of TNF-α (P =.044) at 24 hours vs the MID group, but no significant difference in IL-6 production was found between the 2 groups.
DAO and D-LAC serum levels in the DEX group were significantly different at 0 hours vs 24 hours (P <.05), but no significant differences were observed in the MID group between 0 hours and 24 hours (P >.05). Also, DAO and DLAC serum levels in the DEX group were not significantly different compared with those levels in the MID group at 0 hours (P >.05). DEX was associated with a greater decrease in D-LAC compared with MID at 24 hours vs 0 hours (P <.05).
The α7nAChR level in the DEX group was significantly higher compared with the MID group (P <.05), although no significant change was observed in the level of α7nAChR in the MID group between 0 hours and 24 hours (P >.05). In addition, no significant difference was found in α7nAChR level in the DEX and MID groups at 0 hours, and the α7nAChR level in the DEX group was significantly increased compared with the level in the MID group at 24 hours (P =.015).
“As a sedative, DEX is more suitable for patients undergoing gastrointestinal surgery based on its protection of the intestinal barrier,” the study authors wrote. “The mechanism is potentially related to α7nAChR activation, increased [cholinergic anti-inflammatory pathway] activity, inhibition of the intestinal inflammatory response, and decreased intestinal permeability.”
Qi Y-P, Ma W-J, Cao Y-Y, et al. Effect of dexmedetomidine on intestinal barrier in patients undergoing gastrointestinal surgery—a single-center randomized clinical trial. J Surg Res. Published online April 29, 2022. doi:10.1016/j.jss.2022.03.031