[A Randomized Control Study Comparing the Effects of Tracheal Intubation Performed either via the McGRATH® MAC or the Macintosh Laryngoscope].

Abstract

Background: The McGRATH® MAC (McGRATH) laryngoscope is a newly developed video device, which enables us to perform tracheal intubation minimally invasive. The aim of this study is to evaluate and com- pare the hemodynamic changes triggered by intuba- tion using either the McGRATH or the Macintosh laryngoscope.

Methods: Thirty-seven patients, between 20 and 42 years of age with ASA status I or II, were randomly assigned to two groups : the McGRATH (n=19) or the Macintosh laryngoscope (n=18). Anesthesia was induced with fentanyl 2 μg · kg⁻¹, propofol 2 mg · kg⁻¹, sevoflurane 2%, and rocuronium 0.6 mg · kg⁻¹. We recoded the hemodynamic changes (blood pressure, heart rate) every minute up to 5 minute after intuba- tion. We also recoded the time needed to complete the tracheal intubation. In all cases, the same certified anesthesiologist performed tracheal intubation. Data were presented as mean ± SD. Statistical analyses were performed using the t-test for comparisons of the patients' demographic data, blood pressure, and heart rate between groups.

Results: There were no significant differences in two groups regarding age, weight, height, and sex. Comparing the average time needed to complete the tracheal intubation, the McGRATH group took longer than Macintosh group (40.5 ± 15.3 seconds vs. 29.4? 4.73 seconds, P=0.01). There was no significant differ- ence in blood pressure and heart rate just before tra- cheal intubation. The McGRATH laryngoscope had a significantly lower value than the Macintosh laryngo- scope in systolic pressure (101.2?7.9 vs. 111 ?16.8 mmHg, P=0.03) and heart rate (71.5?9.9 vs. 79.7? 12.3 mmHg, P=0.02) at one minute after tracheal intu- bation.

Conclusions: The McGRATH laryngoscope is less invasive for hemodynamic parameters than the Macin- tosh laryngoscope. These findings suggest that the McGRATH laryngoscope may enable us to perform tracheal intubation less invasively.