Left Head Rotation as an Alternative to Difficult Tracheal Intubation: Randomized Open Label Clinical Trial (Preprint)

Abstract

BACKGROUND Tracheal intubation is a life-saving intervention not only for physicians but also for allied health workers. Optimizing the patient's head and neck position for the best glottic view is a crucial step that accelerates tracheal intubation. The left head rotation maneuver has been recently described as an innovative approach to tracheal intubation with marked improvement in glottic visualization and can be an alternative before proceeding to a surgical airway. OBJECTIVE This study aimed to compare the glottic view and intubating conditions in the sniffing position versus left head rotation during direct laryngoscopy. METHODS This randomized, open-label clinical trial enrolled fifty-two adult patients admitted to the Baguio General Hospital & Medical Center from September to January 2021 for an elective surgical procedure requiring tracheal intubation under general anesthesia. Intubation was done using a 45-degree left head rotation in the experimental group, while the control group was intubated using the conventional sniffing position. Glottic visualization and intubation difficulty with left head rotation and sniffing position were assessed using Cormack-Lehane Grade and Intubation Difficulty Scale, respectively. Successful intubation is measured by observing a capnographic waveform in the end-tidal CO2 monitor after placement of the endotracheal tube. RESULTS There was no significant statistical difference in the clinicodemographic characteristics between the two groups. There was no significant difference in the Cormack-Lehane Grade (P=.45), with the majority of patients classified under Grade 1 (21% in left head rotation and 28% in sniffing position) and Grade 2 (21% in left head rotation and 13% in sniffing position). Also, there were no statistically significant differences (P=.85) in the Intubation Difficulty Scale scores of patients intubated with left head rotation or sniffing position; 17.3% and 15.4% of patients were easily intubated with left head rotation and sniffing position, respectively while slight difficulty was noted with most patients with no between-group differences (26.9% in left head rotation and 30.8% in sniffing position). Greater than one attempt at intubation, use of an alternative technique such as a stylet, and the need for more than one operator were commonly used with left head rotation. The intubation success rate was 100% (26/26) in the sniffing position, while the success rate was 92% (24/26) with left head rotation. CONCLUSIONS Sniffing position provided a higher intubation success rate but with comparable laryngeal exposure and intubation ease to left head rotation. However, since our sample size was small, studies with a larger study population are warranted to establish the generalizability of our findings. In addition, we observed inadequate familiarity among anesthesiologists with the left head rotation technique, and the intubation success rate may improve as practitioners attain greater technical familiarization. CLINICALTRIAL ISRCTN23442026