Haemodynamic Response to Four Different Laryngoscopes

In this prospective randomized study, we aimed to evaluate the effect of tracheal intubation with four different laryngoscopes [Macintosh direct laryngoscope-classic laryngoscope (CL), McCoy (MC), C-Mac video-laryngoscope (CM) and McGrath video-laryngoscope (MG)] on haemodynamic responses in patients with a normal airway.

One hundred and sixty patients were included. Succeeding haemodynamic measurements were performed immediately after intubation (T2) and for 5 min with 1-min intervals (T3-T4-T5-T6-T7). The primary outcome was the heart rate (HR) and systolic blood pressure (SBP) change triggered by the four different laryngoscopes. The intubation time, the number of intubation attempts, need for stylet or additional manipulation, glottic view and traumatic complications caused by intubation procedure were recorded as secondary outcomes.

HR values significantly increased with the completion of laryngoscopy and intubation at T2 for the CL, MC and CM groups. Lesser fluctuation in HR and SBP was observed in the MG group. Intubation time was significantly shorter in the MG group (p<0.001). There was no statistically significant difference between the groups regarding the number of intubation attempts, need for stylette and glottic view. Fewer patients in the MG and CM groups experienced a moderate and severe sore throat than in the other two groups. Shorter intubation time and lesser sore throat incidence were observed in the MG group.

MG offers less haemodynamic stimulation than CL, MC, and CM. Our findings showed that tracheal intubation with MG is advantageous in preventing cardiovascular stress responses with short intubation time and less sore throat incidence.