The sniffing position is recommended for optimal glottic visualization under direct laryngoscopy. However, there is no study assessing whether sniffing position is superior to a neutral position during lightwand-guided intubation. This prospective, randomized study was performed to compare facilitation of lightwand-guided intubation between the sniffing and neutral positions.

The study included 180 patients with normal cervical spines requiring tracheal intubation for elective surgery. Patients were randomly allocated into two groups: neutral or sniffing position. Mallampati class, mouth opening distance, thyromental distance, and laryngeal view grade were measured. A lightwand railroaded with an endotracheal tube was bent 90° at 5 cm from the distal end for both groups. Time to intubation, success rate and intubation time for the first attempt, hydrodynamic changes, and BIS values were recorded.

There were no significant differences in time to intubation, success rate and intubation time of the first trial, hydrodynamic changes, or BIS values between the two positions.

Routine use of the sniffing position does not provide any advantage over the neutral position during lightwand-guided intubation.