Perioperative Dexmedetomidine Improves Outcomes of Kidney Transplant

Perioperative effects of dexmedetomidine on renal function in allogeneic kidney transplant patients: a meta-analysis

BACKGROUND

Allogeneic kidney transplantation represents a cornerstone therapeutic strategy for patients diagnosed with end-stage renal disease. The perioperative management of these patients plays a crucial role in ensuring both optimal graft viability and favorable postoperative outcomes. Dexmedetomidine, a highly selective α2-adrenergic agonist, has attracted considerable attention for its potential renoprotective properties, which are attributed to its anti-inflammatory effects, suppression of sympathetic nervous activity, and ability to stabilize hemodynamics. This meta-analysis was undertaken to systematically integrate the current body of evidence regarding the impact of dexmedetomidine on perioperative renal function in recipients of allogeneic kidney transplants.

METHODS

A systematic and comprehensive search of the literature was conducted using multiple databases-PubMed, Embase, Web of Science, Cochrane Library, and the China National Knowledge Infrastructure (CNKI)-up to March 2025. IEligible studies included those involving adult recipients of allogeneic kidney transplants, wherein dexmedetomidine was administered during the perioperative period, and renal function outcomes such as serum creatinine (Cr), blood urea nitrogen (BUN), urine output, or delayed graft function (DGF) were reported. Two reviewers independently extracted data to ensure objectivity and accuracy; disagreements were resolved by discussion. The pooled data were analyzed using a random-effects model. Statistical heterogeneity was quantified using the I2 statistic, while potential publication bias was assessed through funnel plot symmetry. Sensitivity analyses were conducted to evaluate the robustness of the synthesized results.

RESULTS

Eleven studies comprising 1417 patients were included. Compared to controls, dexmedetomidine significantly reduced serum creatinine levels (SMD = - 0.75, 95% CI - 1.18 to - 0.32, p < 0.001; I2 = 84.1%) and BUN levels (SMD = - 0.87, 95% CI - 1.30 to - 0.44, p = 0.001; I2 = 74.5%). Urine output was significantly increased (SMD = 0.98, 95% CI 0.23 to 1.74, p < 0.001; I2 = 90.0%). The incidence of delayed graft function was lower in the dexmedetomidine group (OR = 0.71, 95% CI 0.52 to 0.97, p = 0.616; I2 = 0.0%). Length of hospital stay was also reduced (SMD = - 0.16, 95% CI - 0.29 to - 0.04, p = 0.364; I2 = 5.9%). Sensitivity analyses confirmed the robustness of the results. No significant publication bias was detected.

CONCLUSION

The results of this meta-analysis support the renoprotective potential of dexmedetomidine when administered during the perioperative phase of allogeneic kidney transplantation. Its use is associated with improvements in key renal function markers, such as reductions in serum creatinine and BUN levels, as well as a decreased incidence of delayed graft function. The observed increase in urine output and shortened hospital stay additionally suggest broader perioperative benefits. Taken together, these findings underscore dexmedetomidine's promise as an adjunct pharmacologic agent in the perioperative care of kidney transplant recipients. Further validation through well-designed, large-scale randomized controlled trials remains essential to inform clinical guidelines.

Dexmedetomidine mitigation of renal ischaemia-reperfusion injury: comprehensive insights from cellular mechanisms to clinical application

Renal ischaemia-reperfusion injury (IRI) is a critical cause of acute kidney injury (AKI) after major surgery, leading to elevated morbidity, mortality, and long-term renal dysfunction. Despite advances in perioperative care, the occurrence of IRI remains high. The renoprotective properties of dexmedetomidine (DEX), a selective α2-adrenergic receptor agonist, have been demonstrated, reducing oxidative stress, inflammation, apoptosis, ferroptosis, cellular senescence, and renal fibrosis while enhancing mitochondrial function and autophagy. From cellular studies to clinical applications, DEX has been effective in mitigating renal IRI, enhancing postoperative renal outcomes, and lowering the incidence of AKI in various surgical settings. This review comprehensively discusses and summarises the renoprotective effects and the underlying mechanisms of DEX, with a focus on its application across various surgical and clinical scenarios. In conclusion, DEX effectively mitigates renal IRI, as evidenced by robust in vitro, in vivo, and clinical studies. It significantly reduces kidney damage and improves surgical outcomes. However, its efficacy is less pronounced in kidney transplantation, suggesting that its renoprotective effects vary depending on the clinical context.

Haemodynamic effect of dexmedetomidine during paediatric kidney transplantation

BACKGROUND

Dexmedetomidine is increasingly used for its ability to stabilise haemodynamic status during general anaesthesia. However, there is currently no data on paediatric kidney transplant recipients (pKTR). This study investigates the haemodynamic impact of dexmedetomidine administered perioperatively in pKTR.

METHODS

From 2019 to 2023, a retrospective study was conducted at Nantes University Hospital involving all pKTR under 18 years of age. The study compared intraoperative haemodynamic parameters between patients administered dexmedetomidine during kidney transplantation (DEX group) and those who did not receive it (no-DEX group). Mean arterial pressure (MAP) and heart rate (HR) were monitored throughout the duration of anaesthesia and compared. Graft function was assessed based on creatinine levels and glomerular filtration rate (GFR) at specific intervals. The perioperative use of fluids and vasoactive drugs, as well as their administration within 24 h post-surgery, were analysed.

RESULTS

Thirty-eight patients were enrolled, 10 in the DEX group and 28 in the no-DEX group. Intraoperative HR was similar between the groups; however, MAP was higher in the DEX group (mean difference 9, standard deviation (SD, 1-11) mmHg, p = 0.039). No differences were found regarding the use of fluid and vasoactive drug therapy between groups. GFR at 1 month post-transplantation was significantly elevated in the DEX group (p = 0.009).

CONCLUSIONS

pKTR receiving intraoperative dexmedetomidine exhibited higher perioperative MAP compared to those not administered dexmedetomidine. Additionally, the DEX group demonstrated superior graft function at 1 month. The direct impact of dexmedetomidine on immediate postoperative graft function in pTKR warrants further investigation in a prospective multicentre randomised study.

Effects of perioperative dexmedetomidine on delayed graft function following renal transplant: a systematic review and meta-analysis

BACKGROUND

Dexmedetomidine, a highly selective alpha-2 adrenoceptor agonist with sedative and analgesic effects, has been suggested in recent studies to possess renoprotective properties. Dexmedetomidine may reduce the incidence of delayed graft function and contribute to effective pain control post-renal transplantation. The primary objective of this systematic review was to assess whether dexmedetomidine decreases the occurrence of delayed graft function in renal transplant patients.

METHODS

Databases including MEDLINE, EMBASE, and CENTRAL were comprehensively searched from their inception until March 2023. The inclusion criteria covered all Randomized Clinical Trials (RCTs) and observational studies comparing dexmedetomidine to control in adult patients undergoing renal transplant surgery. Exclusions comprised case series and case reports.

RESULTS

Ten RCTs involving a total of 1358 patients met the eligibility criteria for data synthesis. Compared to the control group, the dexmedetomidine group demonstrated a significantly lower incidence of delayed graft function (OR = 0.71, 95% CI 0.52-0.97, p = 0.03, GRADE: Very low, I2 = 0%). Dexmedetomidine also significantly prolonged time to initiation of rescue analgesia (MD = 6.73, 95% CI 2.32-11.14, p = 0.003, GRADE: Very low, I2 = 93%) and reduced overall morphine consumption after renal transplant (MD = -5.43, 95% CI -7.95 to -2.91, p < 0.0001, GRADE: Very low, I2 = 0%). The dexmedetomidine group exhibited a significant decrease in heart rate (MD = -8.15, 95% CI -11.45 to -4.86, p < 0.00001, GRADE: Very low, I2 = 84%) and mean arterial pressure compared to the control group (MD = -6.66, 95% CI -11.27 to -2.04, p = 0.005, GRADE: Very low, I2 = 87%).

CONCLUSIONS

This meta-analysis suggests that dexmedetomidine may potentially reduce the incidence of delayed graft function and offers a superior analgesia profile as compared to control in adults undergoing renal transplants. However, the high degree of heterogeneity and inadequate sample size underscore the need for future adequately powered trials to confirm these findings.

Sirtuin 3 in renal diseases and aging: From mechanisms to potential therapies

The longevity protein sirtuins (SIRTs) belong to a family of nicotinamide adenine dinucleotide (NAD+)-dependent deacetylases. In mammals, SIRTs comprise seven members (SIRT1-7) which are localized to different subcellular compartments. As the most prominent mitochondrial deacetylases, SIRT3 is known to be regulated by various mechanisms and participate in virtually all aspects of mitochondrial homeostasis and metabolism, exerting significant impact on multiple organs. Notably, the kidneys possess an abundance of mitochondria that provide substantial energy for filtration and reabsorption. A growing body of evidence now supports the involvement of SIRT3 in several renal diseases, including acute kidney injury, chronic kidney disease, and diabetic nephropathy; notably, these diseases are all associated with aging. In this review, we summarize the emerging role of SIRT3 in renal diseases and aging, and highlights the intricate mechanisms by which SIRT3 exerts its effects. In addition, we highlight the potential therapeutic significance of modulating SIRT3 and provide valuable insights into the therapeutic role of SIRT3 in renal diseases to facilitate clinical application.

The positive efficacy of dexmedetomidine on the clinical outcomes of patients undergoing renal transplantation: evidence from meta-analysis

INTRODUCTION

Whether dexmedetomidine (DEX), an anesthetic adjuvant, can improve renal transplant outcomes is not clear.

METHODS

We systematically identified clinical trials in which DEX was administered in renal transplantation (RT). On November 1, 2022, we searched The Cochrane Library, MEDLINE, EMBASE and https://www.

CLINICALTRIALS

gov/. The main outcomes were delayed graft function and acute rejection.

RESULTS

A total of seven studies were included in the meta-analysis. The results showed that compared with the control, DEX significantly reduced the occurrence of delayed graft function (RR 0.76; 95% CI 0.60-0.98), short-term serum creatinine [postoperative day (POD) 2: (MD -22.82; 95% CI -42.01 - -3.64)] and blood urea nitrogen [POD 2: (MD -2.90; 95% CI -5.10 - -0.70); POD 3: (MD 2.07; 95% CI -4.12 - -0.02)] levels, postoperative morphine consumption (MD -4.27; 95% CI -5.92 - -2.61) and the length of hospital stay (MD -0.85; 95% CI-1.47 - -0.23). However, DEX did not reduce the risk of postoperative acute rejection (RR 0.75; 95% CI 0.45-1.23). The results of the subgroup analysis showed that country type, donor type, and average age had a certain impact on the role of DEX.

CONCLUSIONS

DEX may improve the short-term clinical outcome of RT and shorten the length of hospital stay of patients.

Inflammasome pathway in kidney transplantation

Kidney transplantation is the best available renal replacement therapy for patients with end-stage kidney disease and is associated with better quality of life and patient survival compared with dialysis. However, despite the significant technical and pharmaceutical advances in this field, kidney transplant recipients are still characterized by reduced long-term graft survival. In fact, almost half of the patients lose their allograft after 15-20 years. Most of the conditions leading to graft loss are triggered by the activation of a large immune-inflammatory machinery. In this context, several inflammatory markers have been identified, and the deregulation of the inflammasome (NLRP3, NLRP1, NLRC4, AIM2), a multiprotein complex activated by either whole pathogens (including fungi, bacteria, and viruses) or host-derived molecules, seems to play a pivotal pathogenetic role. However, the biological mechanisms leading to inflammasome activation in patients developing post-transplant complications (including, ischemia-reperfusion injury, rejections, infections) are still largely unrecognized, and only a few research reports, reviewed in this manuscript, have addressed the association between abnormal activation of this pathway and the onset/development of major clinical effects. Finally, the regulation of the inflammasome machinery could represent in future a valuable therapeutic target in kidney transplantation.

Reno-protective effects of perioperative dexmedetomidine in kidney transplantation: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND OBJECTIVE

There is currently no FDA-approved medical therapy for delayed graft function (DGF). Dexmedetomidine (DEX) has multiple reno-protective effects preventing ischemic reperfusion injury, DGF, and acute kidney injury. Therefore, we aimed to evaluate the reno-protective effects of perioperative DEX during renal transplantation.

METHODS

A systematic review and meta-analysis synthesizing randomized controlled trials (RCTs) from WOS, SCOPUS, EMBASE, PubMed, and CENTRAL until June 8th, 2022. We used the risk ratio (RR) for dichotomous outcomes and the mean difference for continuous outcomes; both presented with the corresponding 95% confidence interval (CI). We registered our protocol in PROSPERO with ID: CRD42022338898.

RESULTS

We included four RCTs with 339 patients. Pooled risk ratio found no difference between DEX and placebo in reducing DGF (RR: 0.58 with 95% CI [0.34, 1.01], p = 0.05) and acute rejection (RR: 0.88 with 95% CI [0.52, 1.49], p = 0.63). However, DEX improved short-term creatinine on day 1 (MD: - 0.76 with 95% CI [- 1.23, - 0.3], p = 0.001) and day 2 (MD: - 0.28 with 95% CI [- 0.5, - 0.07], p = 0.01); and blood urea nitrogen on day 2 (MD: - 10.16 with 95% CI [- 17.21, - 3.10], p = 0.005) and day 3 (MD: - 6.72 with 95% CI [- 12.85, - 0.58], p = 0.03).

CONCLUSION

Although there is no difference between DEX and placebo regarding reducing DGF and acute rejection after kidney transplantation, there may be some evidence that it has reno-protective benefits because we found statistically significant improvement in the short-term serum creatinine and blood urea nitrogen levels. More trials are required to investigate the long-term reno-protective effects of DEX.

Delayed graft function: current status and future directions

PURPOSE OF REVIEW

Delayed graft function is a common early posttransplant event predictive of adverse outcomes including hospital readmission, impaired long-term graft function, and decreased graft and patient survival. The purpose of this review is to summarize recent literature describing delayed graft function in hopes of better understanding and managing this condition.

RECENT FINDINGS

Recent research efforts have been garnered towards risk factor modification, prevention, and earlier detection of delayed graft function. In this review, we aim to summarize current innovative approaches and future directions.

SUMMARY

Delayed graft function portends worse graft and patient outcomes. Continued research to prevent, and detect early perturbations in allograft function, and more optimally manage this disease will hopefully improve graft function, along with graft/patient survival.

Effects of perioperative dexmedetomidine infusion on renal function and microcirculation in kidney transplant recipients: a randomised controlled trial

OBJECTIVE

Ischemia-reperfusion injury affects postoperative transplanted kidney function in kidney transplant recipients. Dexmedetomidine was reported to attenuate ischemia-reperfusion injury and improve microcirculation, but its propensity to cause bradycardia and hypotension may adversely affect microcirculation. This study investigated the effect of dexmedetomidine on postoperative renal function and sublingual microcirculation in kidney recipients.

METHODS

The enrolled kidney transplant recipients were randomly allocated to the control group or dexmedetomidine group. After anaesthesia induction, patients in the dexmedetomidine group received dexmedetomidine infusion until 2 h after surgery. Sublingual microcirculation was recorded using an incident dark-field video microscope and analysed. The primary outcomes were the creatinine level on a postoperative day 2 and total vessel density at 2 h after surgery.

RESULTS

A total of 60 kidney recipients were analysed, and the creatinine levels on postoperative day 2 were significantly lower in the dexmedetomidine group than in the control group (1.5 (1.1-2.4) vs. 2.2 (1.7-3.0) mg/dL, median difference -0.6 (95% CI, -0.7 to -0.5) mg/dL, p = .018). On a postoperative day 7, the creatinine levels did not differ significantly between the two groups. Total vessel density at 2 h after surgery did not differ significantly between the two groups.

CONCLUSION

We found that early postoperative renal function was better in kidney transplant recipients receiving dexmedetomidine infusion, but total vessel density was not significantly different between the intervention and control groups. Key messagesIschemia-reperfusion injury affects postoperative transplanted kidney function, and dexmedetomidine was reported to attenuate ischemia-reperfusion injury and improve microcirculation in other clinical conditions.This study showed that early postoperative renal function was better in kidney transplant recipients receiving dexmedetomidine.Dexmedetomidine's side effect of bradycardia and hypotension may affect microcirculation, our results revealed that the perioperative sublingual microcirculation did not differ significantly in kidney transplant recipients receiving dexmedetomidine.

What Is the Role of Dexmedetomidine in Modern Anesthesia and Critical Care?

Dexmedetomidine's unique sedative properties have led to its widespread use. Dexmedetomidine has a beneficial pharmacologic profile including analgesic sparing effects, anxiolysis, sympatholysis, organ-protective effects against ischemic and hypoxic injury, and sedation which parallels natural sleep. An understanding of predictable side effects, effects of age-related physiologic changes, and pharmacokinetic and pharmacodynamic effects of dexmedetomidine is crucial to maximize its safe administration in adults and children. This review focuses on the growing body of literature examining advances in applications of dexmedetomidine in children and adults.

Renoprotective Effect of Intraoperative Dexmedetomidine in Renal Transplantation

BACKGROUND

Renal dysfunction after kidney transplantation may be influenced by many reasons. This study was designed to evaluate whether the administration of dexmedetomidine (Dex) could ameliorate renal function and prognosis after kidney transplantation.

METHODS

A total of 65 patients were divided into Dex group (n = 33) and Con group (Con, n = 32). Dex group intravenously received an initial loading dose of 0.6 μg/kg Dex for 15 min before anaesthesia induction, followed by a rate of 0.4 μg/kg/h until 30 min after kidney reperfusion. By contrast, Con group received saline. The concentration of urinary kidney injury molecule-1 (KIM-1), serum creatinine (Cr), blood urea, urine output, β2 microglobulin (β2-MG), Cystatin C (CysC), and estimated glomerular filtration rate (eGFR) was recorded and compared between two groups during the course of the hospitalization or follow-up. Mean arterial pressure (MAP) and heart rate (HR), vasoactive drugs, and anaesthetics were recorded during the operation. Pain degree was evaluated using a visual analogue scale (VAS) after operation. Delayed graft function (DGF), graft loss, length of hospital stay, and mortality were compared between groups.

RESULTS

The concentration of KIM-1 in Dex group was lower than Con group at 2 h (P = 0.018), 24 h (P = 0.013), 48 h (P < 0.01), and 72 h (P < 0.01) after reperfusion. MAP of Dex group after tracheal intubation (P = 0.012) and incision (P = 0.018) and HR after intubation (P = 0.021) were lower than that of Con group. The dosage of sufentanil during operation in Dex group was less than Con group (P = 0.039). Patients that used atropine in Dex group were more than Con group (P = 0.027). Patients who received Dex presented with lower VAS scores at 6 h (P = 0.01) and 12 h (P = 0.002) after operation. Concentration of serum Cr and blood urea had no significant differences between groups before operation and on postoperative day 1 to 6. Urine output was recorded for 6 days after operation and had no differences between groups. Also, no differences were identified between two groups in urea, Cr, β2-MG, CysC, and eGFR in the first 3 months after operation. Incidence of DGF after operation was detected no difference between groups, while length of hospital stay in Dex group was less than Con group (P = 0.012).

CONCLUSION

Dex can decrease kidney injury marker level, attenuate perioperative stress, relieve the dosage of sufentanil and postoperative pain, and reduce length of hospital stay. However, Dex is not associated with changes in prognosis in the first 3 months after transplantation.

The immunomodulatory mechanism of dexmedetomidine

Dexmedetomidine has been increasingly introduced into the perioperative care of surgical patients. Because a subset of anesthetics/sedatives are immunomodulatory, it is critical to understand the role of dexmedetomidine in our host immune functions. Here we reviewed the role of dexmedetomidine in different immune cells. We also reviewed published clinical articles that described the role of dexmedetomidine in organ injury, cancer surgery, and infection. In animal studies, dexmedetomidine attenuated organ injury. In clinical studies, dexmedetomidine was associated with an improvement in outcomes in cardiac surgery and transplant surgery. However, there is a paucity in research examining how dexmedetomidine is associated with these outcomes. Further studies are needed to understand its clinical application from immunological standpoints.