“…5,6,[35][36][37] Other factors pointed as relevant are the lack of all the material necessary for the procedures, inadequate sedation and analgesia, the lack of pre-oxygenation and ventilation to the patient, traumatic tracheal intubation, and/or various attempts to perform it, incorrect positioning of head and neck, choice of a tracheal tube of improper size, tubes made of improper material. 6,25,35,[37][38][39][40][41] Because this study was conducted in a school hospital, most of the tracheal intubations were performed by resident physicians, who provoked a bigger number of complications, with more attempts of intubation, bradycardia, and hypoxia.…”