Effects of Dexmedetomidine on Microcirculation and Residual Kidney Function in Kidney Donors

Study Overview
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Brief Summary
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Kidney transplant can help patients with end-stage kidney disease to get rid of dialysis and have a good quality life. However, during the renal donation operation, the stress response and subsequent inflammatory responses may result in damage to the residual kidney and transplanted kidney. Dexmedetomidine can increase urine output and decrease the neutrophil gelatinase associated lipocalin level in patients receiving coronary artery bypass surgery. The primary goal of this trial is to investigate the effects of perioperative infusion of dexmedetomidine on the microcirculation and residual kidney function in kidney donors and on the transplanted kidney function in kidney recipients.

Detailed Description
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Kidney transplant can help patients with end-stage kidney disease to get rid of dialysis and have a good quality life. However, during the renal donation operation, the stress response and subsequent inflammatory responses may result in damage to the residual kidney and transplanted kidney. In addition, the transplanted kidney will encounter ischemic and reperfusion injuries during kidney transplant, and it may affect its function. It has been reported in several animal studies that dexmedetomidine can reduce microcirculatory dysfunction, kidney injury, and intestinal injury. Moreover, dexmedetomidine can increase urine output and decrease the neutrophil gelatinase associated lipocalin level in patients receiving coronary artery bypass surgery. The primary goal of this trial is to investigate the effects of perioperative infusion of dexmedetomidine on the microcirculation and residual kidney function in kidney donors and on the transplanted kidney function in kidney recipients. This is a single blind and randomized controlled trial. The participants will be randomly assigned to the Control group or Dexmedetomidine group. The participants in the Control group will receive standard anesthesia care for kidney donation operation. Beside the standard anesthesia care, the participants in the Dexmedetomidine group will receive continuously intravascular infusion of dexmedetomidine since 10 minutes after anesthesia till one hour after operation. At several specific time points, participants will receive sublingual microcirculation examination by using an incident dark field video microscope and blood tests. The chart information will be recorded. The blood creatinine level of the kidney donors and recipients at 1 and 6 months will be recorded.

Official Title
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Effects of Dexmedetomidine on Microcirculation and Residual Kidney Function in Kidney Donors and Transplanted Kidney Function in Kidney Recipients

Conditions
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Kidney Transplant, Microcirculation

Intervention / Treatment
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* Drug: Dexmedetomidine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Kidney Donor for living kidney transplant Exclusion Criteria: Allergy to dexmedetomidine Severe bradycardia < 50 beats per minute before surgery Severe atrioventricular block (the second or third degree) Non-native speaker

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Standard anesthesia care for kidney donor | |
| Experimental: Dexmedetomidine<br>Standard anesthesia care and perioperative infusion of dexmedetomidine for kidney donor | Drug: Dexmedetomidine<br>* Initial infusion dose of dexmedetomidine is 0.4 mcg/kg/min, maintenance infusion dose is 0.1-0.7 mcg/kg/min<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of perfused vessel density | Sublingual microcirculation is measured by incidental dark field video microscope (CytoCam). Perfused vessel density is equal to perfused vessel length (in millimeter) divided by total vessel length (in millimeter) in a square millimeter. | Postoperative 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of creatinine level | change of creatinine level between preoperative and postoperative level | Postoperative 1 day | 
| Change of perfused vessel density | Sublingual microcirculation is measured by incidental dark field video microscope (CytoCam). Perfused vessel density is equal to perfused vessel length (in millimeter) divided by total vessel length (in millimeter) in a square millimeter. | Postoperative 1 day | 
| Change of creatinine level | change of creatinine level between preoperative and postoperative level | Postoperative 1 month | 
| Change of creatinine level | change of creatinine level between preoperative and postoperative level | Postoperative 6 months |