1. Neonatal Intensive Care Unit, Complejo Asistencial Universitario de León, León, Spain
2. Working Group on Bedside Ultrasound of the Spanish Society of Pediatric Intensive Care (SECIP), Madrid, Spain
3. Pediatric Intensive Care Unit, Hospital Universitario Ramón y Cajal, Madrid, Spain
4. Pediatric Intensive Care Unit, Complejo Asistencial Universitario de León, León, Spain