1 Department of Anaesthesiology and Surgical Intensive Therapy, University Medical Centre Ljubljana, Zaloška cesta 7, 1000 Ljubljana, Slovenia.
2 Department of Anaesthesiology and Surgical Intensive Therapy, University Medical Centre Ljubljana, Zaloška cesta 7, 1000 Ljubljana, Slovenia; Institute of Anatomy, Faculty of Medicine, University of Ljubljana, Korytkova ulica 2, 1000 Ljubljana, Slovenia.
3 Department of Pediatric Intensive Care, University Medical Centre Ljubljana, Zaloška cesta 7, 1000 Ljubljana, Slovenia.
4 Institute of Anatomy, Faculty of Medicine, University of Ljubljana, Korytkova ulica 2, 1000 Ljubljana, Slovenia. Electronic address: nejc.umek@mf.uni-lj.si.