Adaptive randomised controlled non-inferiority multicentre trial (the Ketodex Trial) on intranasal dexmedetomidine plus ketamine for procedural sedation in children: study protocol oleh Samina Ali, Serena Hickes, Petros Pechlivanoglou, Quynh Doan, Darcy Beer, Terry Klassen, Anna Heath, Scott Sawyer, Maala Bhatt, Vikram Sabhaney, Kamary Coriolano, April Kam