Continuous hemodiafiltration in children.

Continuous arteriovenous hemofiltration is a form of renal replacement therapy whereby small molecular weight solutes and water are removed from the blood via convection, alleviating fluid overload and, to a degree, azotemia. It has been used in many adults and several children. However, in patients with multisystem organ dysfunction and acute renal failure, continuous arteriovenous hemofiltration alone may not be sufficient for control of azotemia; intermittent hemodialysis or peritoneal dialysis may be undesirable in such unstable patients. Recently, the technique of continuous arteriovenous hemodiafiltration has been used in many severely ill adults. We have used continuous arteriovenous hemodiafiltration in four patients at Children's Hospital Medical Center. Patient 1 suffered perinatal asphyxia and oliguria while on extracorporeal membrane oxygenation. Patients 2 and 4 both had Burkitt lymphoma and tumor lysis syndrome. Patient 3 had septic shock several months after a bone marrow transplant. All had acute renal failure and contraindications to hemodialysis or peritoneal dialysis. A blood pump was used in three of the four patients, while spontaneous arterial flow was adequate in one. Continuous arteriovenous hemodiafiltration was performed for varying lengths of time, from 11 hours to 7 days. No patient had worsening of cardiovascular status or required increased pressor support during continuous arteriovenous hemodiafiltration. The two survivors (patients 2 and 4) eventually recovered normal renal function. Continuous arteriovenous hemodiafiltration is a safe and effective means of renal replacement therapy in the critically ill child. It may be ideal for control of the metabolic and electrolyte abnormalities of the tumor lysis syndrome.