1. Department of Pediatrics; Children's Hospital; University of Helsinki and Helsinki University Central Hospital; Helsinki; Finland
2. Department of Anesthesiology and Intensive Care; Helsinki University Central Hospital; Helsinki; Finland
3. Department of Pediatric Cardiac Surgery; Helsinki University Central Hospital; Helsinki; Finland
4. Institute of Behavioural Sciences; University of Helsinki and Helsinki University Central Hospital; Helsinki; Finland
5. Clinical Laboratory; Finnish Red Cross Blood Service; Helsinki; Finland