Mannitol Use During Cadaveric Kidney Transplantation

Overview

We propose a placebo controlled randomized study on the use of mannitol as an agent to protect against delayed graft function, during the surgical procedure of kidney transplantation from a cadaver. Patients undergoing kidney transplantation for the treatment of end stage kidney disease will be randomized in a ratio of 1:1 to receive either intravenous mannitol or saline during their procedure, administered prior to renal artery clamp release and reperfusion of the kidney. Changes in renal function following surgery and the incidence and duration of delayed graft function (DGF) will be monitored using calculated glomerular filtration rate (eGFR) and the need for dialysis performed post-operatively, as part of routine standard of care. Additionally biological samples will be collected and analyzed for use of a non invasive biomarker for delayed graft function.

This study is a prospective randomized double-blind placebo-controlled trial comparing renal function outcomes in patients undergoing cadaver donor renal transplant for end stage kidney failure. Patients will be randomized to receive 0.5 g / kg body weight, of mannitol or saline 0.9% as an intravenous infusion to be initiated and be completely infused within 15-30 minutes prior to vascular clamp removal of the transplanted renal artery. Prior to surgery, all study participants will receive standard departmental treatment as all other patients undergoing a kidney transplantation from a cadaver. Upon arrival to the operating room patients will be placed supine on the operating room table, and will be connected to an anesthesia monitor which will include monitoring the HR, blood pressure, saturation, temperature and ECG as standard departmental procedure. After connecting the participant to the anesthesia monitor an IV line will be inserted, as is standard clinical practice. In addition, venous central line catheter for central venous pressure monitoring and specific inotropic drugs infusion, as well as arterial line catheter for blood pressure monitoring, will be initialized upon anesthesiologist team decision The technique of kidney transplantation is well-standardized . None of the techniques utilized in the study are considered experimental and all are considered standard therapeutic options for a patient undergoing cadaveric donor kidney transplantation. The procedures are performed under general anesthesia with non-invasive intraoperative vital sign monitoring, as is standard departmental practice. Study participation will not affect anesthesia method or protocol treatment in anyway. Upon study enrollment patients will be randomized in 1:1 ratio for study arm treatment/control. The perioperative team, investigator and patient will be blinded to the intervention. Study arm: Patients randomized to receive the treatment arm will receive 0.5 g / kg body weight of mannitol. The mannitol solution used in the hospital contain 18% mannitol in 500ml solution. An equivocal volume of 2.8 cc / kg body weight, which will be given intravenously with the use of an Ivac pump, infused for a duration of 15 minutes through an existing peripheral intravenous access catheter within 15-30 minutes prior to renal artery reperfusion. The placebo arm (Control arm) Study participants randomized to this arm will receive a 0.9% saline solution at a dose of 2.8 cc / kg, infused within 15-30 minutes prior to renal artery reperfusion through an existing intravenous access catheter (either through an central or peripheral intravenous infusion). Following receiving the study drug, either mannitol or saline, patients will receive 80 mg furosemide, which will be given intravenously. Fluid management throughout the kidney transplant surgery for all study participants will consist as follows: * Upon arrival to the operating room, immediately following IV insertion, all patients will receive an IV infusion of Plasma-Lyte as it is a standard protocol at our institute for kidney transplant surgery. * After induction of anesthesia, the patient will receive Plasma-Lyte solution at a rate of 8 cc / kg body weight per hour. * At this stage of the procedure, before reperfusion of the transplanted kidney, the purpose of this fluid management is intended to maintain a minimum systolic blood pressure of 90-100mmHg. * At 30 to 15 minutes before reperfusion, in purpose to let the transplanted kidney get better opening conditions, the target blood pressure is elevated to an mean arterial pressure (MAP) of not less than 100 mmHg. In order to achieve that, additional 1000 cc of Plasma-Lyte will be given to the patient 30 to 15 minutes before re-perfusion. In addition, small boluses (each 0.1 mg) of Phenylephrine will be given as needed to maintain that MAP. * Thereafter, and until the end of the operation, the fluid management will be titrated according to the patient's blood pressure, ensuring that systolic blood pressure does not fall below 120 mmHG, as the common departmental protocol in such surgeries. In occasions of hypotension, a bolus of 250 cc Plasma-Lyte will be given to increase the blood pressure. * If there is insufficient response to repeat boluses, vasopressors (phenylephrine, ephedrine or noradrenaline) will be given at the discretion of the anesthesiologist. * Episodes of hypotension not responsive to intravenous fluids will be treated with intravenous vasopressors (phenylephrine, ephedrine or noradrenaline as needed) at the discretion of the anesthesiologist. The provision of these drugs will be documented individually in the study report for each patient, as is common clinical practice. * After surgery, in the post anesthesia care unit (PACU), the patient will receive 80 cc / hour of Plasma-Lyte or 120% of urine output if urine output exceeds 80 cc. Patients are regularly supervised in PACU for 2-4 hours after the end of the operation and then transferred to the department of organ transplantation. In cases of need for dialysis or prolonged ventilation, they stay at PACU. * The fluid management for the postoperative days are as standard regimen in our center which consists of giving the patient full fluid replacement at POD1 - including urine output and drains output. On the next post-operative days, we replace 80% of urine output in IV fluids and oral intake together. Additionally blood and urine samples maybe collected from some of the patients (In the event that it is possible) at the following different timelines: Immediately before administering mannitol Immediately after administering mannitol 24 hours after transplant 7 days after transplant, These biological samples will be collected and analyzed to asses the presence of proteins, exosomes , cytokines that can be used as a non invasive biomarker for delayed graft function.