Dexmedetomidine use during orthotopic liver transplantation surgery on early allograft dysfunction: a randomized controlled trial.

BACKGROUND: Previous studies have shown a protective effect of dexmedetomidine use in kidney transplantation. In contrast, it is not known whether intraoperative administration of dexmedetomidine can reduce early allograft dysfunction (EAD) incidence following liver transplantation. OBJECTIVE: To investigate the effect of dexmedetomidine use during surgery on EAD following orthotopic liver transplantation (OLT). STUDY DESIGN: This is a single-center, double-blinded, placebo-controlled randomized clinical trial. Three hundred thirty adult patients undergoing OLT were enrolled from 14th January 2019 to 22nd May 2022. Patients received dexmedetomidine or normal saline during surgery. One year follow-ups were recorded. METHODS: Patients were randomized to two groups receiving either dexmedetomidine or normal saline intraoperatively. For patients in the dexmedetomidine group, a loading dose (1 µg/kg over 10 min) of dexmedetomidine was given after induction of anesthesia followed by a continuous infusion (0.5 µg/kg /h) until the end of surgery. For patients in the normal saline group, an equal volume loading dose of 0.9% saline was given after the induction of anesthesia followed by an equal volume continuous infusion until the end of surgery. The primary outcome was EAD. Secondary outcomes included primary graft nonfunction, acute kidney injury, and acute lung injury/acute respiratory distress syndrome. RESULTS: Of 330 patients included in the intention-to-treat analysis, 165 were in the dexmedetomidine group [mean (SD) age, 49 (10) years; 117 (70.9%) men], and 165 were in the normal saline group [mean SD age, 49 (9) years; 118 (74%) men]. 39 (24.4%) patients in the dexmedetomidine group and 31 (19.4%) in normal saline group developed EAD and the difference was statistically insignificant ( P =0.28). Secondary outcomes including primary graft nonfunction and acute kidney injury was similar between the two groups. CONCLUSION: Intraoperative administration of dexmedetomidine did not reduce EAD rate after OLT.

Study design of the DAS-OLT trial: a randomized controlled trial to evaluate the impact of dexmedetomidine on early allograft dysfunction following liver transplantation.

BACKGROUND: Perioperative ischemia/reperfusion (I/R) injury during liver transplantation is strongly associated with early allograft dysfunction (EAD), graft loss, and mortality. Hepatic I/R injury also causes remote damage to other organs including the renal and pulmonary systems. Dexmedetomidine (DEX), a selective α2-adrenoceptor agonist which is used as an adjuvant to general anesthesia, has been shown in preclinical studies to provide organ protection by ameliorating the effects of I/R injury in a range of tissues (including the liver). However, prospective clinical evidence of any potential benefits in improving outcomes in liver transplantation is lacking. This study aimed to verify the hypothesis that the application of dexmedetomidine during the perioperative period of liver transplantation can reduce the incidence of EAD and primary graft non-function (PNF). At the same time, the effects of dexmedetomidine application on perioperative renal function and lung function were studied. METHODS: This is a prospective, single-center, randomized, parallel-group study. Two hundred participants (18-65 years) scheduled to undergo liver transplantation under general anesthesia will be included in this study. For participants in the treatment group, a loading dose of DEX will be given after induction of anesthesia (1 µg/kg over 10 min) followed by a continuous infusion (0.5 µg/kg /h) until the end of surgery. For participants in the placebo group, an equal volume loading dose of 0.9% saline will be given after the induction of anesthesia followed by an equal volume continuous infusion until the end of surgery. All other supplements, e.g., opioids, sedatives, and muscle relaxant, will be identical in both arms and administered according to routine clinical practice. DISCUSSION: The present trial will examine whether DEX confers organoprotective effects in the liver, in terms of reducing the incidence of EAD and PNF in orthotopic liver transplantation recipients. TRIAL REGISTRATION: ClinicalTrials.gov NCT03770130. Registered on 10 December 2018. https://clinicaltrials.gov/ct2/show/NCT03770130.