B

During in-hospital cardiac arrest the recommended definitive airway, if expertise and equipment are immediately available, is rapid orotracheal (oral) endotracheal intubation; it establishes a secure airway for effective oxygenation and ventilation far more quickly and reliably than nasal intubation, cricothyrotomy, or tracheostomy, which are reserved for failed orotracheal attempts or late situations [Panchal et al., 2019, PMID 31722552; Gough & Nolan, 2018, PMID 29561288].