Comparative evaluation of Intubating Laryngeal Mask Airway (ILMA), I-gel and Ambu AuraGain for blind tracheal intubation in adults

Background and Aims: The supraglottic airway devices (SADs) that allow direct (without an intermediary device like Aintree or airway exchange catheters) tracheal intubation can be invaluable for field use in conditions ideally managed by intubation. Whilst fiberscope-guided intubation is the method of choice, if these ‘direct-intubation’ SADs could provide high success rates for blind tracheal intubation, their scope of use can increase tremendously. Our study assesses intubating laryngeal mask airway (ILMA), i-gel and Ambu AuraGain for blind tracheal intubation in adults. Material and Methods: Ninety adults undergoing elective surgery were randomized into three equal groups. After induction of anesthesia, the group-specific SAD was inserted and on achieving adequate ventilation, blind tracheal intubation was attempted over two attempts. Success rates and time of achieving adequate device placement and tracheal intubation through these were evaluated. Data were analyzed using SPSS version 17.0 and P < 0.05 was considered statistically significant. Results: All three devices could achieve adequate ventilation within two allowed attempts. Successful tracheal intubation rates were significantly better with ILMA than i-gel on first attempt (87% vs. 27%, P < 0.001) and after second attempt that was supplemented with optimization maneuvers (100% vs. 40%, P < 0.001). No patient could be intubated through Ambu AuraGain within two attempts. Time taken for successful tracheal intubation did not differ significantly ( P = 0.205) with ILMA or i-gel. Conclusion: Out of ILMA, I-gel and Ambu AuraGain, ILMA is the best device for blind tracheal intubation in adults with normal airways.