Forearm support to reduce dental contact during direct laryngoscopy: a randomized crossover trial

Traumatic dental injury is a common complication of tracheal intubation. We aimed to compare the incidence of dental contact during laryngoscopy between the conventional technique and a novel technique that maintains head extension using the practitioner's left forearm or elbow to support the patient's forehead.

We conducted a single-centre randomized crossover trial in 84 adult patients who were scheduled for elective surgery requiring tracheal intubation. Each patient underwent both the novel and conventional laryngoscopy techniques in a randomized sequence. The primary outcome was the incidence of dental contact during direct laryngoscopy. Secondary outcomes included blade-to-tooth distance, angle of head extension, percentage of glottic opening (POGO) score, and POGO scores of 4 or 5.

The novel technique significantly reduced the incidence of dental contact compared with the conventional technique (44/84 [52%] vs 65/84 [77%]; P < 0.001). Additionally, the novel technique achieved a longer blade-to-tooth distance (median difference [interquartile range (IQR)], 0 [0-1] mm; P = 0.001), wider angle of head extension (mean difference, 4.5°; 95% confidence interval, 2.1 to 6.8; P < 0.001), higher POGO score (median difference [IQR], 1 [0-1]; P = 0.003), and higher proportion of POGO scores of 4 or 5 (75/84 [89%] vs 61/84 [73%]; P = 0.01).

Compared with conventional laryngoscopy, a novel laryngoscopy technique that maintains head extension using the practitioner's left forearm or elbow to support the patient's forehead significantly reduced the risk of dental contact, increased the blade-to-tooth distance and the angle of head extension, and provided better glottic visualization. This simple, effective approach can reduce the risk of traumatic dental injury and improve safety during direct laryngoscopy.

https://www.

gov ( NCT05495880 ); first submitted 8 August 2022.