Comparison of the Efficacy of Macintosh Laryngoscope-guided Insertion of I-gel™ with the Conventional Blind Insertion Technique - A Randomised Study

Background And Aims: This study was designed to compare the efficacy of Macintosh laryngoscope-guided insertion of I-gel™ with the conventional blind insertion technique.

Methods: A total of 156 adult patients scheduled to undergo elective surgery under general anaesthesia were included. All participants were randomly divided into two groups; I-gel™ was inserted with conventional blind and Macintosh laryngoscopic-guided technique in group A and B respectively. The primary objective of the study was to determine the incidence of optimal positioning in both the groups based on fibreoptic bronchoscope score of the glottic view. Oropharyngeal leak pressure, haemodynamic parameters and insertion characteristics were also compared. Categorical data were presented as ratio or percentage, continuous data were presented as mean ± standard deviation or median (95% confidence interval). The strength of association between insertion technique and the anatomical fit of the device was calculated by relative risk ratio.

Results: Fibreoptic scores were significantly better in laryngoscope-guided insertion group when compared to the blind insertion group ( < 0.0001). The incidence of malposition was 3.85% in the laryngoscopic insertion group and 39.4% in the blind insertion ( < 0.0001). Oropharyngeal leak pressure was higher in laryngoscope-guided insertion group than in blind insertion group (26.89 ± 3.37 cm HO versus 24.42 ± 3.00 cm HO; < 0.0001). Other insertion characteristics except time taken to insert the device were comparable in both groups.

Conclusion: When compared to the standard blind insertion technique, laryngoscope-guided insertion of I-gel™ results in better alignment with the laryngeal inlet providing a proper anatomical fit and better airway seal pressure.