[1] Great Ormond St Hosp Children NHS Fdn Trust, Cardiac Intens Care Unit, Crit Care & Cardioresp Div, London, England
[2] Alder Hey Childrens Hosp, Paediat Intens Care Unit, Liverpool L12 2AP, Merseyside, England
[3] Univ Hosp Cologne, Dept Anaesthesiol & Intens Care Med, Cologne, Germany
[4] Univ Hosp Cologne, Dept Pediat Cardiol, Ctr Heart, Cologne, Germany
[5] Bambino Gesu Children Hosp, Dept Cardiol & Cardiac Surg, Anaesthesia & Pediat Cardiac Intens Care, Rome, Italy