Risk of extracorporeal life support circuit-related hyperkalemia is reduced by prebypass ultrafiltration.

OBJECTIVES: Pediatric patients who receive large volume blood transfusions are at risk for experiencing transfusion-related hyperkalemic cardiac arrest. Prebypass ultrafiltration of blood used to prime cardiopulmonary bypass circuits is commonly used in pediatric cardiac surgery to create a more physiologic and electrolyte balanced priming solution prior to initiation of cardiopulmonary bypass. This study was undertaken to determine the efficacy of prebypass ultrafiltration in normalizing extracorporeal life support circuit priming solution before initiating extracorporeal life support. DESIGN: Prospective study. SETTING: PICU and neonatal ICU in a tertiary academic center. PATIENTS: Patients requiring venovenous extracorporeal life support. INTERVENTIONS: Prebypass ultrafiltration of extracorporeal life support circuits. MEASUREMENTS AND MAIN RESULTS: Hematocrit, electrolyte, and lactate concentrations were measured in blood-primed extracorporeal life support circuits before and after ultrafiltration and in blood collected from patients before and after initiation of extracorporeal life support. Clinically significant elevation of K concentration was observed in all extracorporeal life support circuits prior to prebypass ultrafiltration, despite the fact that 93% of red blood cell units were collected ≤ 7 days prior to use. Prebypass ultrafiltration significantly reduced concentrations of K (10.9 vs 6.0 mEq/L, p = 0.001) and lactate (7.0 vs 3.6 mmol/L, p < 0.001) and increased hematocrit (37% vs 48%, p < 0.001) and concentrations of ionized calcium (0.64 vs 1.16 mg/dL, p < 0.001) and Na (129 vs 144 mEq/L, p < 0.001). Serum electrolyte concentrations remained within the normal physiologic range in all patients following initiation of venovenous extracorporeal life support with circuits that underwent prebypass ultrafiltration. CONCLUSIONS: Prebypass ultrafiltration normalizes the electrolyte balance of blood-primed extracorporeal life support circuits. Prebypass ultrafiltration processing may reduce the risk of transfusion-related hyperkalemic cardiac arrest in small children who require venovenous extracorporeal life support.

Challenging Argatroban Management of a Child on Extracorporeal Support and Subsequent Heart Transplant.

A 6-year-old child developed heparin-induced thrombocytopenia while on extracorporeal life support. Hours after a difficult transition from heparin to argatroban for anticoagulation therapy, the child underwent heart transplantation. Intraoperative management was plagued with circuit thrombus formation while on cardiopulmonary bypass and subsequent massive hemorrhage after bypass. We review the child's anticoagulation management, clinical challenges encountered, and review current literature related to the use of argatroban in pediatric cardiac surgery.