Comparison of Laryngoscopic Glottic Views Obtained via Macintosh vs Miller Blade in Adults Undergoing General Anesthesia with Endotracheal Intubation

Abstract

Objective: To compare the glottic views obtained through Miller and Macintosh blade laryngoscopy in adults undergoing general anesthesia with endotracheal intubation. Methodology: This quasi-experimental study was conducted at Holy Family Hospital, Rawalpindi, from June 2022 to September 2022. Sixty patients scheduled for elective surgery under general anesthesia with endotracheal intubation were enrolled. Patients were randomly assigned to two groups: Miller blade group (n=30) and Macintosh blade group (n=30). The anesthesiologist conducting the intubation recorded the Cormack Lehane grade obtained. Data analysis utilized SPSS version 27.0, employing independent-sample t-tests, Mann-Whitney U tests, chi-square, or Fisher's exact tests as appropriate. A p-value <0.05 was considered statistically significant. Results: In the Miller blade group, comprising 30 patients, the mean age was 44.60+13.310 years, and 53.3% were male. Cormack-Lehane grades were distributed as follows: 76.7% grade I, 20.0% grade II, and 3.3% grade III. In the Macintosh blade group, with 30 patients, the mean age was 40.93+12.798 years, and 46.7% were male. Cormack-Lehane grades were distributed as follows: 30.0% grade I, 50.0% grade II, 13.3% grade III, and 6.7% grade IV. Conclusion: The study concluded that Miller blade laryngoscopy provides superior glottic views compared to Macintosh blade laryngoscopy. However, the ease of intubation and the time taken for intubation were not investigated, suggesting areas for exploration in future studies.