Hemodynamic responses to endotracheal intubation performed with video and direct laryngoscopy in patients scheduled for major cardiac surgery

Abstract

This study aims to compare the hemodynamic responses to endotracheal intubation performed with direct and video laryngoscope in patients scheduled for cardiac surgery and to assess the airway and laryngoscopic characteristics. One hundred ten patients were equally allocated to either direct Macintosh laryngoscope (n = 55) or indirect Macintosh C-MAC video laryngoscope (n = 55). Systolic, diastolic, and mean arterial pressure, and heart rate were recorded prior to induction anesthesia, and immediately and two minutes after intubation. Airway characteristics (modified Mallampati, thyromental distance, sternomental distance, mouth opening, upper lip bite test, Wilson risk sum score), mask ventilation, laryngoscopic characteristics (Cormack-Lehane, percentage of glottic opening), intubation time, number of attempts, external pressure application, use of stylet and predictors of difficult intubation (modified Mallampati grade 3-4, thyromental distance < 6 cm, upper lip bite test class 3, Wilson risk sum score ≥ 2, Cormack-Lehane grade 3-4) were recorded. Hemodynamic parameters were similar between the groups at all time points of measurement. Airway characteristics and mask ventilation were no significant between the groups. The C-MAC video laryngoscope group had better laryngoscopic view as assessed by Cormack-Lehane and percentage of glottic view, and a longer intubation time. Number of attempts, external pressure, use of stylet, and difficult intubation parameters were similar. Endotracheal intubation performed with direct Macintosh laryngoscope or indirect Macintosh C-MAC video laryngoscope causes similar and stable hemodynamic responses.

Keywords: Macintosh C-MAC video laryngoscope; cardiac surgery; endotracheal intubation; hemodynamic response.