Comparison of McGRATH MAC and Macintosh laryngoscopes for double-lumen endotracheal tube intubation by anesthesia residents: a prospective randomized clinical trial

STUDY OBJECTIVE

This study aimed to compare the utility of McGRATH MAC (McG) and Macintosh (McL) laryngoscopes for double-lumen endotracheal tube intubation in patients undergoing elective surgery.

DESIGN

Randomized clinical trial.

SETTING

Operating room.

PATIENTS

Fifty adult patients scheduled for elective surgery under 1-lung ventilation with American Society of Anesthesiologists physical status 1 to 3.

INTERVENTIONS

Double-lumen endotracheal tube intubation was performed with the McG (McG group; 25 patients) or conventional McL (McL group; 25 patients) laryngoscope by anesthesia residents.

MEASUREMENTS

The number of attempts to successful intubation, intubation time, percentage of glottis opening score, and subjective difficulty of laryngoscopy and tube passage through the glottis were assessed.

MAIN RESULTS

The total numbers of intubation attempts were 1 (McG group, 24 patients; McL group, 16 patients), 2 (McG group, 1 patient; McL group, 8 patients), and 3 (McG group, 0 patient; McL group, 1 patient), with significant differences between the two groups (P = .018). Intubation time was significantly shorter in the McG group compared with the McL group (McG: 17.1 ± 4.6 seconds vs McL: 20.8 ± 5.9 seconds, P = .026). The percentage of glottis opening score was significantly higher in the McG group compared with the McL group (McG: 88.4% ± 13.7% vs McL: 71.4% ± 20.4%, P = .004).

CONCLUSIONS

The McG demonstrated a better intubation profile compared with the McL, possibly due to its ease of use for double-lumen endotracheal tube intubation. Clinical Trial registry number: UMIN000014636.