A comparison of direct laryngoscopic views in different head and neck positions in edentulous patients



      Proper head and neck positioning is an important factor for successful direct laryngoscopy, and the optimum position in edentulous patients is unclear. We compared direct laryngoscopic views in simple head extension, sniffing, and elevated sniffing positions in edentulous patients.


      Eighteen adult edentulous patients scheduled for elective surgery were included in the study. After induction of anesthesia, the laryngeal view was assessed under direct laryngoscopy using the percentage of glottic opening (POGO) score in 3 different head and neck positions in a randomized order: simple head extension without a pillow, sniffing position with a pillow of 7 cm, and elevated sniffing position with a pillow of 10 cm. After assessment of the laryngeal views, tracheal intubation was performed.


      A significant difference was observed in the laryngeal views assessed at the 3 head positions (P= .001). The POGO scores (mean [SD]) in the sniffing position (78.9% [19.7%]) and elevated sniffing position (72.6% [20.8%]) were significantly improved compared to that with simple head extension (53.8% [25.9%]) (P= .001, respectively). The sniffing position provided the best laryngeal view. The mean POGO scores were higher in the sniffing position than the elevated sniffing position, but no significant difference was observed between these 2 positions (P= .268).


      The sniffing and elevated sniffing positions provide better laryngeal views during direct laryngoscopy compared to simple head extension in edentulous patients.
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