Original Article Safety of therapeutic hypothermia in children on veno-arterial extracorporeal membrane oxygenation after cardiac surgery Song Lou, 1,2 Graeme MacLaren, 1,3,4 Eldho Paul, 5 Derek Best, 1 Carmel Delzoppo, 1 Yves d’Udekem, 3,6 Warwick Butt 1,3 1 Paediatric Intensive Care Unit, Royal Children’s Hospital, Parkville, Melbourne, Australia; 2 State Key Laboratory of Cardiovascular Disease, Department of Cardiopulmonary Bypass, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, Beijing, People’s Republic of China; 3 Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia; 4 Cardiothoracic Intensive Care Unit, National University Health System, Singapore; 5 School of Public Health and Preventive Medicine, Monash University; 6 Department of Cardiac Surgery, The Royal Children’s Hospital, Melbourne, Victoria, Australia Abstract Objective: The aim of this study was to evaluate whether the use of therapeutic hypothermia in patients receiving extracorporeal membrane oxygenation after paediatric cardiac surgery is associated with increased complication rates. Methods: We undertook a retrospective study to compare the complication rates and clinical course of children after cardiac surgery in two groups – extracorporeal membrane oxygenation without therapeutic hypothermia (group 1) and extracorporeal membrane oxygenation with therapeutic hypothermia (group 2). Therapeutic hypothermia was performed via the extracorporeal membrane oxygenation circuit heater– cooler device. Results: A total of 96 patients were included in this study (59 in group 1 and 37 in group 2). Complications were comparable between group 1 and group 2, except that more patients with therapeutic hypothermia had hypertension while on extracorporeal membrane oxygenation. Therapeutic hypothermia was not independently associated with in-hospital mortality (adjusted odds ratio 1.16, 95% CI: 0.33–4.03; p = 0.82). Conclusion: Therapeutic hypothermia can be safely provided to children on extracorporeal membrane oxygenation after cardiac surgery without an increase in complication rates. Keywords: Extracorporeal life support; paediatric; outcomes; bleeding Received: 4 June 2014; Accepted: 18 January 2015; First published online: 27 February 2015 T HE ROLE OF THERAPEUTIC HYPOTHERMIA IN critical illness is actively debated. Uncertain- ties abound regarding precise indications, technique, duration, and potential benefits. There is some evidence that therapeutic hypothermia may improve survival and mitigate both cardiac and brain injury, particularly after cardiac arrest. For example, in one animal study, 24 hours of extracorporeal membrane oxygenation support was performed with animals being randomised to either hypother- mia (33°C) or normothermia. The hypothermia group showed improved survival as well as better cerebral and cardiac outcomes. 1 Hypothermia is also associated with improved survival and better neurodevelopmental outcomes in newborns with moderate-to-severe hypoxic ischaemic encephalopa- thy. 2 The American Heart Association recommends hypothermia for the treatment of neurological injury following resuscitation from out-of-hospital cardiac arrest when the initial cardiac rhythm is ventricular fibrillation. 3 Despite potential complications such as arrhyth- mias, 4 coagulation dysfunction, 5 and infection, 6 The work was performed at the Royal Children’s Hospital, Melbourne, Australia. Correspondence to: G. MacLaren, c/o Paediatric Intensive Care Unit, Royal Children’s Hospital, Flemington Rd, Parkville, VIC 3052, Australia. Tel: + 6 139 345 5211; Fax: +6139 345 5977; E-mail: gmaclaren@iinet.net.au Cardiology in the Young (2015), 25, 1367–1373 © Cambridge University Press, 2015 doi:10.1017/S1047951115000116