[1] Autonomous Univ Barcelona, Hosp Infantil Vall Hebron, Dept Otolaryngol, Catalonia, Spain
[2] Autonomous Univ Barcelona, Hosp Infantil Vall Hebron, Dept Paediat Surg, Catalonia, Spain
[3] Autonomous Univ Barcelona, Hosp Infantil Vall Hebron, Dept Paediat Cardiac Surg, Catalonia, Spain
[4] Autonomous Univ Barcelona, Hosp Infantil Vall Hebron, Dept Anaesthesia, Catalonia, Spain