Comparison of Macintosh, Truview EVO2®, Glidescope®, and Airwayscope® laryngoscope use in patients with cervical spine immobilization

Background. The purpose of this study was to evaluate the effectiveness of the Pentax AWS®, Glidescope®, and the Truview EVO2®, in comparison with the Macintosh laryngoscope, when performing tracheal intubation in patients with neck immobilization using manual in-line axial cervical spine stabilization. Methods. One hundred and twenty consenting patients presenting for surgery requiring tracheal intubation were randomly assigned to undergo intubation using a Macintosh (n=30), Glidescope® (n=30), Truview EVO2® (n=30), or AWS® (n=30) laryngoscope. All patients were intubated by one of the three anaesthetists experienced in the use of each laryngoscope. Results. The Glidescope®, AWS®, and Truview EVO2® each reduced the intubation difficulty score (IDS), improved the Cormack and Lehane glottic view, and reduced the need for optimization manoeuvres, compared with the Macintosh. The mean IDS was significantly lower with the Glidescope® and AWS® compared with the Truview EVO2® device, and the IDS was lowest with the AWS®. The duration of tracheal intubation attempts was significantly shorter with the Macintosh compared with the other devices. There were no differences in success rates between the devices tested. The AWS® produced the least haemodynamic stimulation. Conclusions. The Glidescope® and AWS® laryngoscopes required more time but reduced intubation difficulty and improved glottic view over the Macintosh laryngoscope more than the Truview EVO2® laryngoscope when used in patients undergoing cervical spine immobilization.