Challenging Dogma: Videolaryngoscopy to Limit Cervical Spine Injury?

Videolaryngoscopy is recommended for tracheal intubation of patients with known or suspected cervical spine injury, and current multidisciplinary guidance grounds that recommendation in improved first-attempt success. A separate and widely repeated rationale, that videolaryngoscopy is preferable because it produces less cervical spine movement than direct laryngoscopy, persists in teaching and at the bedside. We examine the primary literature bearing on this motion-reduction rationale. Videolaryngoscopy does reduce cervical spine motion relative to direct laryngoscopy, but the reductions are small, a few degrees at most, and are concentrated at the upper cervical segments; they were not significant at C4-C5, the lowest segment assessed. The trials also enrolled only patients without spinal cord injury, and the clinical significance of these reductions is unestablished. Biomechanical modeling indicates that even routine laryngoscopy force keeps intervertebral motion within physiologic limits, and no study has demonstrated that the smaller motion produced by videolaryngoscopy translates into a lower rate of neurologic deterioration, secondary cord injury, or any patient-important outcome. The distribution of cervical spine injuries, which cluster at C2 and across the lower cervical segments, only partially overlaps the segments where videolaryngoscopy confers its motion advantage. We argue that videolaryngoscopy is a reasonable and often preferable choice in this population, but for reasons of first-attempt success rather than for a motion-reduction mechanism that has not been linked to outcome.