Mannitol Versus Nitroglycerin for Kidney Injury Prevention in Robotic-assisted Radical Prostatectomy or Cystectomy

"Nitroglycerin prepared using a vial (50 mg nitroglycerin) transferred into a 500 ml glass bottle of sodium chloride injection (0.9%), this yields a concentration of 100 mcg/ml.~Patients in the nitroglycerin group will receive nitroglycerin infusion at a rate of 0.25 mic/kg/min all through the surgery, to be discontinued in the PACU."

"Mannitol will be prepared through diluting 100 ml of the 20% solution with 180 ml of sodium chloride injection (0.9%).~Patients in the mannitol group will receive an infusion bolus of mannitol 20% 0.5gm/kg added to the standard fluid chart via centeral line.~Mannitol intake will be started directly after induction of anaesthesia and before intra-peritoneal gas insufflation, as an infusion over 15 minutes."

"Patients will take the standard fluid chart, as the patient will receive the estimated maintenance \& deficit requirements according to 4/2/1 rule.~In case of hypotension, (defined as 20% decrease from the baseline), administration of a fluid bolus of 200 ml ringer will be done.~Blood loss more than 10% of estimated blood volume will initiate blood transfusion using 1:1 ratio. Additional fluids may be administered postoperatively according to the patient's volume status."