Evaluation of the Effects of Remifentanil and Dexmedetomidine on Renal Functions in a Rat Model of Crush Injury

Background and Objectives: Crush injury frequently leads to acute kidney injury (AKI) through rhabdomyolysis, and the choice of anesthetic agent may influence renal outcomes in patients requiring surgery after such injury. This study aimed to compare the effects of remifentanil and dexmedetomidine on renal injury following crush injury using biochemical markers and histopathological examination. Materials and Methods: In this experimental study, 28 male Wistar-Albino rats were allocated to four groups (n = 7 each): Control, Sham (crush injury and surgery without drug), Dexmedetomidine, and Remifentanil. Bilateral gastrocnemius compression for two hours induced crush injury, followed by a one-hour intravenous drug infusion and simulated laparotomy. Blood samples were collected at 0, 2, and 6 h; animals were sacrificed at 6 h and kidney tissue was harvested. Serum urea, creatinine, neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), (TIMP-2) × (IGFBP7), total antioxidant capacity (TAC), and total oxidative status (TOS) were measured, and renal histopathology was evaluated. One Sham-group animal died during the experiment; the final analysis included 27 animals. Results: When all time points were evaluated together, serum creatinine and NGAL levels were significantly higher in the Remifentanil group than in the Dexmedetomidine group (although creatinine was already higher in the Remifentanil group at 2 h, before drug administration), whereas KIM-1 and (TIMP-2) × (IGFBP7) did not differ significantly between groups. The correlation between TAC and TOS was weakly positive early after injury and became weakly negative by 6 h. Histopathological analysis showed more pronounced necrosis, brush-border loss, and congestion in the Remifentanil group, whereas renal tissue preservation was more evident in the Dexmedetomidine group; these mixed biochemical results do not uniformly support a renoprotective conclusion. Conclusions: In this experimental crush injury model, dexmedetomidine was associated with more favorable early renal biochemical and histopathological findings than remifentanil, suggesting a potential renoprotective association. However, the mixed biomarker findings, small sample size, and short observation period preclude a definitive conclusion regarding direct renal protection.