Impact of Continuous Perioperative Dexmedetomidine Infusion on Postoperative Renal Function Among Patients Undergoing Kidney Transplantation: a Randomized Controlled Trial

Dexmedetomidine, an alpha 2 agonist, is being increasingly used in recent years for the maintaining of anesthesia as it allows sedation and analgesia with only a modest respiratory depression effect when compared to opioids and inhaled anesthetic agents and allows maintenance of spontaneous ventilation. Most common side effects are bradycardia and hypotension. Drug's metabolism is exclusively hepatic and therefor do not require dosage adaptation for patient's kidney function.

Post-Operative acute kidney injury (AKI) is a common complication after major surgery and might incur serious adverse outcomes such as longer hospital stay, dialysis, chronic kidney disease and death. The most common theory for the occurrence of post-operative AKI is the ischemic-reperfusion syndrome.

Several in vitro animal studies as well as human studies have suggested the nephroprotective effects of per-operative continuous infusion of dexmedetomidine and its ability to decrease post-operative AKI.

Kidney transplantation (KT) is the treatment of choice for patients with End Stage Renal Disease. It is considered a major surgery and it was shown that optimized perioperative management could improve post-operative outcomes such as early graft function as measured by urine output and serum creatinine trends. However, delayed graft function (DGF), which is defined by the need for dialysis within the first seven days after transplantation remains a significant issue for post-operative KT care with an incidence of up to 30%.

A retrospective study of 780 patients receiving KT, has shown that preoperative dexmedetomidine could significantly decrease occurrence of DGF. Recently, two single-center, randomized controlled trials, with similar sample sizes of 104 and 111 patients, compared peri-operative continuous infusion of dexmedetomidine to placebo. One study failed to show significant impact on DGF incidence while the second showed a significant 50% reduction in DGF in the dexmedetomidine group. Due to increasing evidence concerning the nephroprotective effects and improved post-operative outcomes of perioperative continuous dexmedetomidine infusion, a larger, multi-center randomized-controlled trial to study and potentially confirm the evidence in the settings of KT would be of benefit.

The aim of our study is to assess whether the perioperative continuous infusion of dexmedetomidine during KT could improve peri-operative renal function among KT recipients as compared to placebo.