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.

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 ).

A Randomised Control Study Comparing C-MAC D-Blade Video Laryngoscope (Hyper Angulated Blade) and Macintosh Laryngoscope for Insertion of a Double-Lumen Tube in Patients Undergoing Elective Thoracotomy.

Background: The use of a double-lumen endotracheal tube is one of the common anesthetic techniques for operations in the thoracic cavity. However, when compared to a single-lumen tube, placement of a double-lumen tube is technically more difficult as a result of which it takes more time to insert and is associated with more complications such as mucosal injury, hoarseness, and sore throat, even in patients with no anticipated airway difficulty. The CMAC D-blade that is usually used in patients with anticipated airway difficulty, could assist in smooth and quick placement of double-lumen tube (DLT) even in patients with no anticipated airway difficulty. Aim of the Study: This study aimed to evaluate the effectiveness of the C-MAC D-blade in reducing the time taken to visualize the glottis and intubate patients with normal airway with a double-lumen tube. Setting and Design: This was a prospective open-label randomized control trial in a tertiary hospital. Materials and Methods: Seventy-three consenting adult patients with physical status classes I and II, as determined by the American Society of Anesthesiologists, scheduled to undergo elective thoracotomy, were randomly allocated to receive either C-MAC D-blade (Group D) or Macintosh blade (Group M). The primary objective was to compare the time taken for visualization of the glottis and intubation. Statistical Analysis Used: Chi-square/Fisher's exact test and t-test were used for statistical analysis. Results: Seventy-three patients were randomized (Group D = 36; Group M = 37). Time to visualize the glottic structures (4.56 ± 2.396 s vs. 7.27 ± 4.891 s, P = 0.01) was significantly better in Group D; however, the mean intubation time was comparable (55.92 ± 18.749 s vs. 51.08 ± 15.269 s, P = 0.61). Conclusion: C-MAC D-blade videolaryngoscope offers a better glottic view and lesser time to visualize glottis when compared with the Macintosh laryngoscope. However, the time taken to insert the DLT after visualization was longer. We infer that there is no advantage in the routine use of C-MAC D-blade for DLT insertion in patients with no anticipated airway difficulty.