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Randomized Controlled Trial
. 2020 Aug 15;20(1):201.
doi: 10.1186/s12871-020-01118-3.

Randomized crossover trial comparing cervical spine motion during tracheal intubation with a Macintosh laryngoscope versus a C-MAC D-blade videolaryngoscope in a simulated immobilized cervical spine

Affiliations
Randomized Controlled Trial

Randomized crossover trial comparing cervical spine motion during tracheal intubation with a Macintosh laryngoscope versus a C-MAC D-blade videolaryngoscope in a simulated immobilized cervical spine

Hyesun Paik et al. BMC Anesthesiol. .

Abstract

Background: Maintaining cervical immobilization is essential during tracheal intubation in patients with unstable cervical spines. When using the Macintosh laryngoscope for intubation in patients with cervical immobilization, substantial neck extension is required for visualization of the glottis. However, the C-MAC D-Blade videolaryngoscope may require less neck extension due to its acute angulation. We hypothesized that C-MAC D-Blade videolaryngoscopic intubation would result in less cervical spine movement than Macintosh laryngoscopic intubation. We compared the effects of C-MAC D-Blade videolaryngoscopic intubation and Macintosh laryngoscopic intubation in terms of cervical spine motion during intubation in patients with simulated cervical immobilization.

Methods: In this randomized crossover study, the cervical spine angle was measured at the occiput-C1, C1-C2, and C2-C5 segments before and during tracheal intubation with either a C-MAC D-Blade videolaryngoscope or Macintosh laryngoscope in 20 patients, with application of a neck collar for simulated cervical immobilization. Cervical spine motion was defined as the change in angle measured before and during tracheal intubation.

Results: The cervical spine motion at the occiput-C1 segment was measured at 12.1 ± 4.2° and 6.8 ± 5.0° during Macintosh laryngoscopic and C-MAC D-blade videolaryngoscopic intubation, respectively, corresponding to a 44% reduction in cervical spine motion when using the latter device (mean difference, - 5.3; 98.33% CI: - 8.8 to - 1.8; p = 0.001). However, there was no significant difference between the two intubation devices at the C1-C2 segment (- 0.6; 98.33% CI: - 3.4 to 2.2; p = 0.639) or C2-C5 segment (0.2; 98.33% CI: - 6.0 to 6.4; p = 0.929).

Conclusions: The C-MAC D-Blade videolaryngoscope causes less upper cervical spine motion than the Macintosh laryngoscope during tracheal intubation of patients with simulated cervical immobilization.

Trial registration: This study was registered at ClinicalTrials.gov on June 26, 2018 ( NCT03567902 ).

Keywords: C-MAC D-blade videolaryngoscope; Cervical immobilization; Cervical spine motion; Intubation; Macintosh laryngoscope.

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Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
CONSORT flow diagram
Fig. 2
Fig. 2
Vertebral reference lines. The reference line for the occiput was defined as a line between the base of the sella and the opisthion (line a), and the C1 reference line as a line between the lower cortical margin of the anterior arch of C1 and the lower cortical margin of the C1 spinous process (line b). The C2 reference line was defined as a line between the anterior, inferior margin of the C2 body and the lower cortical margin of the C2 spinous process (line c). The C5 reference line was a tangent along the superior end-plate of the C5 vertebral body (line d)
Fig. 3
Fig. 3
Cervical spine angles measured at three cervical segments before and during intubation with the C-MAC D-Blade videolaryngoscope (open circle) and the direct Macintosh laryngoscope (closed circle). Values are shown as mean ± SD. *: p < 0.05 vs. C-MAC D-Blade videolaryngoscope

References

    1. Crosby E. Airway management after upper cervical spine injury: what have we learned? Can J Anaesth. 2002;49(7):733–744. doi: 10.1007/BF03017455. - DOI - PubMed
    1. Brimacombe J, Keller C, Kunzel KH, Gaber O, Boehler M, Puhringer F. Cervical spine motion during airway management: a cinefluoroscopic study of the posteriorly destabilized third cervical vertebrae in human cadavers. Anesth Analg. 2000;91(5):1274–1278. doi: 10.1213/00000539-200011000-00041. - DOI - PubMed
    1. Maruyama K, Yamada T, Kawakami R, Hara K. Randomized cross-over comparison of cervical-spine motion with the AirWay scope or Macintosh laryngoscope with in-line stabilization: a video-fluoroscopic study. Br J Anaesth. 2008;101(4):563–567. doi: 10.1093/bja/aen207. - DOI - PubMed
    1. Turkstra TP, Craen RA, Pelz DM, Gelb AW. Cervical spine motion: a fluoroscopic comparison during intubation with lighted stylet, GlideScope, and Macintosh laryngoscope. Anesth Analg. 2005;101(3):910–915. doi: 10.1213/01.ane.0000166975.38649.27. - DOI - PubMed
    1. El-Tahan MR, El Kenany S, Khidr AM, Al Ghamdi AA, Tawfik AM, Al Mulhim AS. Cervical spine motion during tracheal intubation with king vision video laryngoscopy and conventional laryngoscopy: a crossover randomized study. Minerva Anestesiol. 2017;83(11):1152–1160. - PubMed

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