Hemodynamic response related to the Airway Scope versus the Macintosh laryngoscope: A systematic review and meta-analysis with trial sequential analysis

Background: It is important to reduce the hemodynamic response during tracheal intubation. We performed a systematic review and meta-analysis of the Airway Scope and Macintosh laryngoscope to determine whether they reduce the hemodynamic responses of heart rate (HR) and mean blood pressure (MBP) after tracheal intubation under general anesthesia. Methods: We performed a comprehensive literature search of electronic databases for clinical trials comparing hemodynamic response to tracheal intubation. The primary aim of our meta-analyst is to determine if the Airway Scope reduces hemodynamic responses (HR and mean MBP) 60 seconds after tracheal intubation compared to the Macintosh laryngoscope. We expressed pooled differences in hemodynamic responses between the 2 devices as weighted mean differences with 95% confidence intervals. We conducted trial sequential analysis. Secondarily, we investigated the ability of the Airway Scope and Macintosh laryngoscope to reduce hemodynamic responses at 120 seconds, 180 seconds, and 300 seconds after tracheal intubation. Results: We identified clinical trials comparing hemodynamic response via a comprehensive literature search. Of 185 articles found in the search, we selected 8. In comparison to the Macintosh laryngoscope, the Airway Scope significantly reduced HR and MBP at 60 seconds after tracheal intubation (HR; weighted mean difference = -7.29; 95% confidence interval, -10.9 to -3.62; P <.0001; I2 = 57%, MBP; weighted mean difference = -11.5; 95% confidence interval, -20.4 to -2.65; P =.01; I2 = 91%). At the secondary outcome, the Airway Scope significantly reduced the fluctuation of HR after 120 seconds and 180 seconds of tracheal intubation. However, the Airway Scope did not significantly reduce MBP 120 seconds, 180 seconds, and 300 seconds after tracheal intubation. Trial sequential analysis suggested that the total sample size reached the required information size for heart rate. Conclusions: Our finding suggested that the Airway Scope attenuated hemodynamic responses at 60 seconds after tracheal intubation in comparison with that of the Macintosh laryngoscope. However, the MBP sample size is small and further research is needed.