Objective: To assess the risk of hyperkalemia with blood-primed extracorporeal life support (ECLS) circuits in infants < 10 kg.
Design: Retrospective cohort study of all neonatal and pediatric patients < 10 kg placed on ECLS from May 1998 to April 2001.
Measurements and main results: Data collection including patient weight, patient potassium levels pre- and post-initiation of ECLS, potassium level of the primed ECLS circuit, age of the packed red blood cell (PRBC) unit, type of preservative, and preservative reduction status. Seventy-six circuits were available for the analysis. The age of the PRBC unit and preservative reduction status significantly affected the potassium level of the primed ECLS circuit. Multivariate linear regression analysis showed no significant effect on the post-ECLS initiation patient potassium level with respect to the PRBC age, the preservative reduction status, the patient potassium level prior to ECLS initiation, and the potassium level of the primed ECLS circuit.
Conclusions: Initiation of ECLS in infants < 10 kg should not be delayed unnecessarily to perform preservative reduction or to utilize PRBC units of a specific age, as hyperkalemia of the primed ECLS circuit is not associated with systemic hyperkalemia in the patient post-initiation of ECLS.