A simulated 'can't intubate, can't oxygenate' manikin crossover study investigating a modified front-of-neck access airway device

A 'can't intubate, can't oxygenate' (CICO) situation is an uncommon and time-critical emergency. Many institutions have adopted a 'scalpel-bougie-endotracheal tube (ETT)' technique based on evidence produced by the 4th National Audit Project of the Royal College of Anaesthetists and 2015 Difficult Airway Society guidelines. We made a modification to the traditional 'scalpel-bougie-ETT' technique, using a shortened bougie and replacing the ETT with a cuffed Melker airway in a preassembled device (called 'Secure Airway for Front-of-neck Emergencies' (SAFE airway device)), which we felt might reduce cognitive load on a single operator in an emergency CICO situation. We then performed a simulation crossover study using 20 volunteer anaesthetic doctors to compare this modification with the traditional technique. After a standardised pre-recorded video demonstration, participants performed simulated tube insertion using both the standard 'scalpel-bougie-ETT' technique and the SAFE airway device in randomised order. Participants were filmed for accurate timestamping. The primary outcome was time to successful tube insertion while secondary outcomes included number of attempts and ease of insertion. Overall time to cuff inflation was shorter, statistically and practically, with the SAFE airway device compared with the ETT (median 30 vs. 52 seconds, P < 0.001). Twenty-five percent of participants required multiple attempts using the ETT method versus 5% using the SAFE airway device, which was also rated as being easier to use. This study demonstrates that the SAFE airway device was fast, effective, easy to use and acceptable to airway practitioners in a simulated manikin environment. These findings indicate that further studies of the SAFE airway device are warranted.