Background: The use of a shoulder roll to view the glottic opening during direct laryngoscopy in infants has been recommended but is not evidence based.
Methods: Twenty infants with normal airways, <6 months of age undergoing elective surgery under general anesthesia were randomized to undergo direct laryngoscopy first with a 2-inch vertical shoulder roll and then without, or vice versa. The primary outcome was the difference in the vertical distance between the angle of the laryngoscopist's eye and the operating room table in the 2 positions. Also, the views of the glottic opening in both positions were recorded for each infant and analyzed by a blinded investigator using the percent of glottic opening (POGO).
Results: Twenty infants completed the study without complications. The vertical distance did not differ significantly whether the shoulder roll was placed first or second, and there was no evidence of a differential carryover effect in the crossover design (P = .268). The main effect of the shoulder roll on the mean (95% confidence interval [CI]) vertical distances without 47.8 cm (43.5-52.1) and with the shoulder roll 37.2 cm (33.3-41) yielded a mean (95% CI) vertical difference of 10.6 cm (9.3-11.79; P = .0001). The median (interquartile range [IQR]) POGO scores without 100 [86.2, 100] and with the shoulder roll 97.5 [80, 100] did not differ (median difference [95% CI]: 0 [-20 to 0]; P = .39).
Conclusions: A 2-inch shoulder roll lowers the line of sight of the glottic opening compared with no shoulder roll, without affecting the view of the glottic opening during laryngoscopy in infants.
Trial registration: ClinicalTrials.gov NCT03424070.