Fluoroscopic Comparison of Cervical Spine Motion Using LMA CTrach, C-MAC Videolaryngoscope and Macintosh Laryngoscope

Objective: Endotracheal intubation should be performed with care when cervical spine (C-spine) injury is suspected. The aim of this study was to evaluate the movement of the C-spine using fluoroscopy during intubation with Laryngeal Mask Airway (LMA) CTrach, C-MAC videolaryngoscope and Macintosh laryngoscope. Methods: This was a single-centre, prospective, observational, controlled trial. In total, 22 surgical patients aged 18-65 years planned to undergo operation under general anaesthesia, were enrolled. X-ray images of the C-spine were obtained using fluoroscopy with the patients' head in a neutral position. All patients underwent laryngoscopy using a Macintosh blade, LMA CTrach and C-MAC videolaryngoscope, and fluoroscopic images of the C-spine were obtained. All the patients were intubated at the last laryngoscopy simulation (using the C-MAC). The atlanto-occipital distance (AOD) and angles between C0C1, C0C2, C0C3, C0C4, C1C2 and C2C3 lines were measured and compared between each device. Results: The mean AOD was measured as 20.4 mm in a neutral position, which decreased to 13.1, 17.2 and 12.3 mm after the insertion of the Macintosh laryngoscope, LMA CTrach and C-MAC videolaryngoscope, respectively. The differences were significant (p < 0.001). Moreover, significant difference was noted in C0C2, C0C3 and C1C2 angles with the insertion of the three devices (p < 0.001). The LMA CTrach resulted in significantly lesser C-spine movements in C0C2, C0C3 and C0C4 angles compared to the Macintosh laryngoscope and C-MAC videolaryngoscope (p < 0.001). Conclusion: The LMA CTrach resulted in lesser C-spine movements compared to Macintosh laryngoscope and C-MAC videolaryngoscope. In case of the C-spine injury, LMA CTrach may be preferred and may cause fewer traumas during endotracheal intubation.