Intravascular volumes and colloid dynamics in relation to fluid management in living related kidney donors and recipients

This study examines our current perioperative fluid regimen in relation to body fluid compartments, intravascular volumes, and early kidney function in 17 kidney transplant recipients and their living related donors. Donors were given 0.5 g/kg of 10% dextran-40 during surgery and electrolyte solutions averaging 3032 ml/24 h. Recipients were randomized to receive albumin or dextran-40 infusions and given 0.5 g/kg during surgery. Electrolyte and 5% glucose infusions averaged 5580 ml/24 h, to match the urinary output. Total intravascular albumin (TIA) and total intravascular dextran (TID) were calculated from the plasma concentrations and plasma volume (PV). Mean preoperative PV in the donors was 44.5 ml/kg. The TIA loss of 0.37 g/kg was balanced by a TID of 0.27 g/kg, and PV increased to 46 and 49 ml/kg at 3 and 34 h after surgery, respectively. In recipients, the preoperative volume of extracellular water correlated linearly to the total body water and PV, as well as to the urine flow the first 24 h after transplantation. No difference was found in urine volume, serum creatinine, or PV expansion between recipient patients receiving albumin or dextran-40. Twelve patients with immediate urinary onset had blood volume (BV) and PV of more than 70 and 45 ml/kg, respectively, in sharp contrast to five patients with delayed urinary onset, who had lower BV and PV values. A fall in TIA of 0.9 g/kg at 3 h corresponded to a PV loss of 18 ml/kg and was only partially replaced by the 0.5 g/kg of intraoperative colloids. We conclude that BV and PV of more than 70 and 45 ml/kg, respectively, are associated with immediate kidney function in living related transplant recipients. Immediate kidney function may be induced by colloid infusions in a dose of about 1 g/kg, in addition to electrolyte solutions and blood transfusions.