McGrath® versus Macintosh laryngoscopes on hemodynamic response to intubation in elderly patients: a randomized clinical trial.

Introduction: laryngoscopy and tracheal intubation induce catecholaminergic release. Our study aimed to evaluate the hemodynamic impact of orotracheal intubation by McGrath® compared to the Macintosh laryngoscope in the elderly.

Methods: we conducted a prospective randomized clinical trial that included elderly patients proposed for a scheduled surgery under general anesthesia with orotracheal intubation and divided into 2 groups: patients who were intubated using the McGrath® (group V) and patients who were intubated using the Macintosh direct laryngoscope (group M). Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial blood pressure (MAP), were recorded before induction of anesthesia (baseline), and at 1 min, 3 min, and 5 min after intubation. Our outcomes were the increase of SBP (∆ SBP), MAP (∆ MAP), and HR (∆ HR) between the two groups, during the 5 minutes following the start of the orotracheal intubation, intubation time and the incidence of its related complications.

Results: sixty patients were included and randomized into 2 groups of 30. The average age of our sample was 70±6 years with a sex ratio of 1.22. Most of the patients were operated on for orthopedic, urologic, or abdominal surgery. There were no statistically significant differences between the two groups in terms of demographic characteristics and the duration of anesthesia (p> 0.05). The intubation time was significantly increased in group M (p≤0.001). There was a significant difference in SBP, MAP, and HR values at 1 min after orotracheal intubation compared with the baseline values in Group V(P<0,05) and Group M (p < 0.05). There was a significant increase in the first minute after tracheal intubation in terms of SBP (151±42 vs 134.5±26 mmHg, p=0.012), MAP (114±4 vs 102±17 mmHg, p=0.015), DBP (89±32 vs 84±16 mmHg, p=0.01), and HR (99.5±10 vs 94.5±2 b/min, p=0.008) when group M was compared to group V. The ∆SBP was significantly different between group M (∆SBP = 36.2±23.5mmHg) and group V (∆SBP= 30.77±21.6mmHg) (p = 0.005). There were 4 ventricular arrhythmias in group M versus zero in group V (p <0.0001). The postoperative sore throat was significantly decreased in group M vs V (p=0.036).

Conclusion: the McGrath® videolaryngoscope decreased the hemodynamic fluctuations due to endotracheal intubation in elderly patients.