1 Neonatal Intensive Care Unit, School of Medicine, University of Ioannina, Ioannina, Greece

2 Department of Pediatrics, School of Medicine, University of Ioannina, Ioannina, Greece 3 Respiratory Unit, Third Department of Pediatrics, Athens University Medical School, ”Attikon” University Hospital, Haidari, Greece

Funding : This research received no external funding.

Conflicts of Interest: The authors declare no conflicts of interest.