Anesth Pain Med.  2023 Oct;18(4):431-438. 10.17085/apm.23079.

The sniffing position facilitated easier light wand guided endotracheal intubation compared with the neutral position with chin-lift

• Kim GH
• Jung EJ
• Han YJ
• Yun MJ

• KMID: 2550924
• DOI: http://doi.org/10.17085/apm.23079

Abstract

Background
Traditionally, the patient's head is placed in a neutral position with a chin-lift to facilitate light wand guided endotracheal intubation. However, our study found that the sniffing position was more effective. In this study, we aimed to compare the two positions of light wand guided endotracheal intubation. Methods: Sixty adult patients were included in the study, after obtaining informed consent, and were randomly assigned to one of two groups: a control group in a neutral position with a chin-lift (group C, n = 30) and a sniffing position group (group S, n = 30). In group C, the anesthesiologist inserted a light wand after lifting the patient's mandible using the thumb of their non-dominant hand inside the patient's mouth. In group S, a light wand was inserted after the patient's head was flexed with the neck extended. We assessed variables such as light-search time, number of intubation attempts, time to achieve intubation, and side effects including blood tinge on the endotracheal tube, hoarseness, sore throat, and anesthesiologist satisfaction. Results: The light-search and intubation times were shorter in group S than in group C. The incidence of blood tinge on the endotracheal tube was higher in group C than in group S. Anesthesiologist satisfaction was higher in group S than in group C. Conclusions: The sniffing position was more effective in facilitating light wand guided endotracheal intubation than the neutral position with a chin-lift.

Keyword

Anesthetics; Intubation; Light; Transillumination; Chin

Figure

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  Fig. 1. To achieve the neutral position with chin-lift, an 8 cm pillow is placed under the patient’s head. The anesthesiologist positions their non-dominant hand’s thumb near the patient’s molar teeth while their remaining four fingers hold the mandible angle, lifting the jaw in an antero-caudal direction. The anesthesiologist’s dominant hand is used to hold the light wand.

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  Fig. 2. In the sniffing position group, a pillow measuring 8 cm in height was positioned under the patient’s head to induce neck flexion, while the anesthesiologist extended the patient’s head at the atlanto-occipital joint using their non-dominant hand. This posture naturally opens the patient’s mouth. The anesthesiologist holds the light wand with their dominant hand.

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  Fig. 3. Group C: control group of a neutral position with chin lift, Group S: sniffing position group.

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