The Effects of a Shoulder Roll During Laryngoscopy in Infants: A Randomized, Single-Blinded, Crossover Study.

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.

A randomized trial of the glottic views with the classic Miller, Wis-Hipple and C-MAC (videolaryngoscope and direct views) straight size 1 blades in young children.

STUDY OBJECTIVE: The Miller and Wis-Hipple size 1 blades are widely used for laryngoscopy in children and the C-MAC straight blade is used increasingly in young children, although the glottic views with these blades have not been compared. To determine whether the glottic views with these blades are equivalent. DESIGN: Equivalent study. SETTING: Operating room. PATIENTS: 96 children <2 years, ASA 1 or 2, elective surgery requiring orotracheal intubation. INTERVENTIONS: Direct laryngoscopy with the Miller and Wis-Hipple or C-MAC (videolaryngoscope and direct view) straight blades size 1; photographs of the glottic opening. MEASUREMENTS: Percent of glottic opening (POGO) was measured using a standardized scale by a blinded investigator. Heart rate, systolic blood pressure and hemoglobin oxygen saturation were measured before and after laryngoscopy. RESULTS: The POGO scores with the four blades/views were equivalent (fewer than 20% of the views yielded POGO scores <80). However, a post hoc comparison of the POGO scores yielded significant differences (P = 0.0001); the C-MAC videolaryngoscope view yielded significantly better scores than the Miller, Wis-Hipple and direct C-MAC views (P = 0.0009, 0.0002 and 0.0001 respectively). The POGO score with the Miller blade was superior to that with the direct C-MAC view (P = 0.024). No adverse events or complications occurred. CONCLUSION: The four blades/glottic views were equivalent, although a post hoc analysis demonstrated that the glottic view with the C-MAC videolaryngoscope was superior overall and the view with the Miller size 1 was superior to that with the direct C-MAC view.