A Comparison of the Effects of Different Types of Laryngoscope on the Cervical Motions: Randomized Clinical Trial

Abstract

Background: The rate of cervical injury among all trauma patients is 3.1%. The most important point during intubation of those patients is not to increase the cervical injury.

Aims: In this study, we hypothesize that there will be a minimal cervical extension during a laryngoscopy with the use of optical view laryngoscopes.

Study design: Prospective, randomized clinical trial.

Methods: One hundred and fifty adult patients with ASA physical status I to III were enrolled in our study. After routine anesthesia induction, we randomly assigned the patients into three groups according to the type of laryngoscope. Macintosh type, Truview EVO2(®) type and Airtraq® type laryngoscopes were used in Group DL (n=50), Group TW (n=50) and Group ATQ (n=50), respectively. After applying general anesthesia induction and mask ventilation, all of the patients were positioned in the neutral position. An inclinometer was placed on the forehead of the patients. Then, the extension angle during intubation and the Cormack-Lehane Score were measured and the time to intubation was recorded.

Results: One of the 50 patients in the DL Group, 2 of the 50 patients in the TW Group, and 4 of the 50 patients in the ATQ Group were excluded from the study because of the failure of intubation at defined times. The angle of cervical extension during laryngoscopy was found to be 27.24±6.71, 18.08±7.53, and 14.54±4.09 degrees in the Groups DL, TV and ATQ, respectively; these differences also had statistical significance (p=0.000). The duration of intubation was found to be 13.59±5.49, 23.60±15.23, and 29.80±13.82 seconds in Groups DL, TV and ATQ, respectively (p=0.000).

Conclusion: A minimal cervical motion was obtained during tracheal intubation with the use of Truview EVO2® and Airtraq® types of laryngoscope compared with the Macintosh laryngoscope. (ClinicalTrials.gov Identifier: NCT02191904).

Keywords: Airtraq®; Macintosh; Truview EVO2®; airway management; intratracheal equipment; intubation.

Figures

FIG. 1.

Flow chart of patient enrolment and analysis

FIG. 2.

Head in the neutral position

FIG. 3.

Inclinometer measurements from the head in extension