1. From the Departments of Pediatric Cardiothoracic Surgery (S.O.A., P.H.S., F.H.), Pediatric Intensive Care (N.J.G.J.), Biostatistics (I.v.d.T.), Anesthesiology (A.N.J.S.), and Intensive Care and Emergency Medicine, Neonatology (F.G., M.T., I.C.v.H., L.S.d.V.), University Medical Center Utrecht, Utrecht, The Netherlands; and HaemoScan, Groningen, The Netherlands (W.v.O.).