1 General and Thoracic Surgery Unit, Bambino Gesù Children Hospital IRCCS, Rome, Italy. Electronic address: alessandro.crocoli@opbg.net.
2 Department of Anesthesiology, Santobono-Pausilipon Children's Hospital of Naples, Italy. Electronic address: lucasidro@fastwebnet.it.
3 Department of Anesthesiology, Giannina Gaslini Institute, Genoa, Italy. Electronic address: cle77d@yahoo.it.
4 Department of Anesthesia, Children's Hospital 'Meyer', Firenze, Italy. Electronic address: frossetti.74@gmail.com.
5 Department of Surgery, "A. Gemelli" Teaching Hospital, Catholic University of the Sacred Heart, Rome, Italy. Electronic address: mauropittiruti@me.com.