CONTINUOUS VENOVENOUS HEMODIALYSIS IN A NEONATE MODEL - A 2-PUMP SYSTEM

Objective: To evaluate the efficiency and tolerance of venovenous hemo filtration, hemodiafiltration, and hemodialysis with a two-pump system in a neonatal animal model of acute renal failure. Design: Prospectiv e trial. Setting: Animal laboratory at a large university-affiliate me dical center. Subjects: New Zealand white rabbits, weighing 3325 +/- 3 80 g. Interventions: Venovenous hemofiltration, hemodiafiltration, and hemodialysis were performed in anesthetized rabbits with previous bil ateral ureteral ligation. Measurements and Main Results: At a blood fl ow rate of 19 +/- 0.5 mL/min, we determined hematocrit, urea, creatini ne, and electrolyte values in brood, at the inlet and outlet of the he mofilter, and in ultrafiltrate at the start and after 15, 30, 60, 90, 120, and 180 mins of hemofiltration (ultrafiltrate flow rate of 1.9 +/ - 0.2 mL/min), hemodiafiltration (dialysate plus ultrafiltrate flow ra te of 16.9 +/- 0.8 mL/min), and hemodialysis (dialysate flow rate of 1 5.7 +/- 1.1 mL/min). Arterial blood pressure, heart rate, and body tem perature were monitored during the procedures. Urea and creatinine ins tantaneous clearances were higher with hemodiafiltration (8.0 +/- 0.7 and 6.2 +/- 0.7, respectively, n = 29) and hemodialysis (6.8 +/- 1.1 a nd 4.8 +/- 0.9, respectively, n = 31) than with hemofiltration (1.8 +/ - 0.6 and 1.9 +/- 0.4, respectively, n = 16). Initial and final weight s, temperatures, and hematocrit, sodium, and protein blood concentrati ons of each 180-min procedure were similar. Conclusions: Hemodiafiltra tion had a higher urea removal rate than hemodialysis but the manageme nt of hemodiafiltration was more cumbersome and time consuming in the absence of a flow equalizer device. As a result, we recommend continuo us venovenous hemodialysis as the therapy of choice.