Intubating Position: Is the "Sniffing" Position Better Than Simple Extension?

The "sniffing" position, which requires flexion of the neck on the body and extension of the head on the neck, is widely recognized as the optimal position for direct laryngoscopy. Investigators in France used magnetic resonance imaging to assess intubating conditions in three positions -- neutral; simple extension; and the sniffing position, in which a cushion was placed under the occiput of the extended head. Subjects were 8 healthy, adult volunteers (age, 32+/-3 years) without markers of difficult intubation. Angles between the axes of the mouth, pharynx, and larynx were measured in each position.

None of the positions aligned the three axes. Both simple extension and sniffing improved the angle between the line of vision and the laryngea…