Comparison of cervical spine motion during intubation with a C‑MAC D‑Blade® and an LMA Fastrach®

This prospective randomized study compared cervical motion during intubation with a C‑MAC D‑Blade® and with a laryngeal mask airway LMA Fastrach®.

The participants in this study were 52 ASA I-III patients aged 18-70 years and assigned for elective cervical discectomy. The patients were randomly selected for intubation with a C‑MAC D‑Blade® (group V) or an LMA Fastrach® laryngeal airway (group F). Both groups received the same induction of anaesthesia. The first lateral view was X‑rayed while the head and neck were in a neutral supine position and the second exposure was taken during the passage of the endotracheal tube through the vocal cords for group V and during the advance of the endotracheal tube for group F. The occiput-C1 (C0-C1), C1-C2 and C2-5 angles were measured. The angle formed by the line between the occipital protuberance and anterior process of the foramen magnum and the line between the central point of C1 spinous process and the anterior process of the foramen magnum was defined as angle A. The differences between the angles were calculated. Overall intubation success and first-pass success (success at the first attempt) were recorded.

The change in angulations between C0-C1 during intubation was significantly lower in group F than in group V (2.78⁰ ± 2.1⁰ vs. 6.04⁰ ± 4.1⁰, p = 0.007). Before intubation, angle A was 14.4⁰ ± 3.9⁰ in group V and 13.8⁰ ± 3.7⁰ in group F (p = 0.627). During intubation, angle A was significantly smaller for group V than for group F (9.1⁰ ± 2.4⁰ vs. 10.7⁰ ± 2.9⁰, p = 0.04). The number of successful intubations were significantly higher in group V (100% of intubations were successful on the first attempt for group V, vs. 80% for group F, p = 0.023).

Intubation with both a C‑MAC D‑Blade and a Fastrach LMA resulted in cervical motion but within safe ranges. Intubation with a C-mac D blade might be preferred because the Fastrach LMA may result in more failed intubation attempts in patients with cervical spine disorders.