Abstract
Continuous arteriovenous hemofiltration (CAVH) is an increasingly popular technique in the care of critically ill children. The operating characteristics of the available circuits are largely unknown. Prior to introducing CAVH into our pediatric intensive care unit, we investigated the performance of three CAVH circuits: CAVH with postfilter dilution, CAVH with prefilter dilution (CAVHpre) and CAVH with dialysis counterflow. Using a neonatal lamb model, we measured filter blood flow (QB), ultrafiltrate rate (QU), arterial, venous and ultrafiltrate compartment pressure, oncotic pressure, plus urea levels in blood and ultrafiltrate fluid for the three CAVH circuit designs. Transmembrane pressure and urea clearance were calculated for various values of QB after varying a clamp on the arterial side of the circuit. The major finding, applicable to all circuits, was the wide variability of QB. Constant attention was required in order to obtain a consistent QB. Fluid clearance was effective with all three circuits. Urea clearance averaged 5–10 ml/min and was principally dependent on QU and independent of QB. The addition of dialysis counterflow did not increase urea clearance. The most convenient circuit we tested was CAVHpre, but the problem of unstable QB is common to all unpumped arteriovenous filtrate circuits. It is a major limiting factor in the practical application of this technology to critically ill children.
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References
Zobel G, Ring E, Zobel V (1989) Continuous arteriovenous replacement systems for critically ill children. Pediatr Nephrol 3: 140–143
Lieberman KV (1987) Continuous arteriovenous hemofiltration in children. Pediatr Nephrol 1: 330–338
Pascual JF, Lopez JD, Molina M (1987) Hemofiltration in children with renal failure. Pediatr Clin North Am 34: 803–818
Bosch JP (1986) Continuous arteriovenous hemofiltration: operational characteristics and clinical use. Am Kidney Foundation Nephrol Lett 3: 15–26
Kaplan AA (1986) Clinical trials with predilution and vacuum suction. Enhancing the efficiency of CAVH treatment. Trans Am Soc Artif Intern Organs 22: 49–51
Peachey TD, Ware RJ, Eason JR, Parsons V (1988) Pump control of continuous arteriovenous haemodialysis. Lancet/II: 878
Stevens PE, Riley B, Davies SP, Gower PE, Brown EA, Kox W (1988) Continuous arteriovenous haemodialysis in critically ill patients. Lancet II: 150–152
Assadi FK (1988) Treatment of acute renal failure in an infant by continuous arteriovenous hemodialysis. Pediatr Nephrol 2: 320–322
Lieberman KV, Nardi L, Bosch JP (1985) Treatment of acute renal failure in an infant using continuous arteriovenous hemofiltration. J Pediatr 106: 646–649
Ronco C, Brendolan A, Bragantini L, Chiaramonte S, Feriani M, Fabris A, Dell'Aquila R, La Greca G (1986) Treatment of acute renal failure in newborns by continuous arterio-venous hemofiltration. Kidney Int 29: 908–915
Golper TA, Ronco C, Kaplan AA (1988) Continuous arteriovenous hemofiltration: improvements, modifications, and future directions. Semin Dial 1: 50–54
Anonymous (1990) Operating instructions for the AmiconTM and Minifilter plusTM. Package insert, Amicon Division, Grace
Hiyama DT, Weiss RG, Ryckman FC (1989) Factors affecting urea clearance during continuous hemodiafiltration in the canine model. J Pediatr Surg 24: 756–759
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Werner, H.A., Herbertson, M.J. & Seear, M.D. Operating characteristics of pediatric continuous arteriovenous hemofiltration in an animal model. Pediatr Nephrol 7, 189–193 (1993). https://doi.org/10.1007/BF00864394
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DOI: https://doi.org/10.1007/BF00864394