Foulds LT et al., Anaesthesia 2016 Feb 5;
In this randomized operating-room study, the McGrath Series 5 video laryngoscope led to better glottic views and fewer intubation failures compared with direct laryngoscopy.
Previous studies have shown McGrath video laryngoscopy to be superior to direct laryngoscopy when patients are intubated with manual in-line cervical stabilization and an opened collar (NEJM JW Emerg Med Oct 2014 and Anaesthesia 2014; 69:1345; NEJM JW Emerg Med Mar 2013 and Anaesthesia 2013; 68:142). Whether this holds true when a semi-rigid collar is left in place is unknown.
Investigators applied a semi-rigid collar to each of 50 patients without known cervical spine injury or pathology who were undergoing elective surgery. Patients were then randomized to laryngoscopy first with a Macintosh laryngoscope followed by intubation with a McGrath Series 5 video laryngoscope or to the opposite sequence. A malleable stylet with a 60° bend was used for all McGrath intubations. Patients in both groups were induced, paralyzed, and positioned in identical fashion.
Glottic view, the primary endpoint, was similar or better with the McGrath in all patients. Intubation was successful in all patients intubated with the McGrath, while there were seven failures (28%) in the group intubated with the Macintosh (desaturation in 1 patient; difficulty passing the endotracheal tube in the others). There were no significant differences between groups in time to tube placement or rate of adverse events (hypoxia, dental or pharyngeal trauma).
Collar on or collar off, it doesn’t matter: Video laryngoscopy is better than direct laryngoscopy for patients requiring intubation in neutral cervical spine position.