Comparison of 2 Different Techniques of LMA Insertion Namely Traditional Standard Technique of Blind Insertion and Use of Laryngoscope for Guided Insertion of LMA for Successful Placement in an Anatomical Position

Author(s): Naveen Gowda R.S.1 , Suresh C.2 , Chandrashekar E.3

BACKGROUND Determining the optimum insertion technique is very critical because unsuccessful prolonged insertion time and multiple attempts are associated with adverse respiratory and traumatic injuries. The present study was undertaken to compare two different LMA insertion techniques, namely conventional ‘Standard’ technique and the use of laryngoscope for guided insertion in terms of ease of insertion for successful placement in an ideal anatomical position. We also studied the complications such as pharyngeal trauma, sore throat, and any haemodynamic alterations. METHODS Fifty patients were selected from either sex form 15 - 50 years age group, ASA I and II and posted for elective surgery for which general anaesthesia was provided. They were divided into two groups, randomly (n = 25 each). For group A, the airway was secured with Classic LMA of appropriate size with the blind standard technique and for group B, laryngoscopy was used for guided under vision insertion. These two groups were compared in terms of a primary end point i) ease of insertion for successful placement in an ideal anatomical position, based on number of attempts, time required, change of technique, and volume of air required for tight seal, secondary end points ii) pharyngeal trauma, sore throat after its removal and any changes in hemodynamic parameters at 0, 5, 10, 15 minutes of LMA insertion. For statistical significance the differences are compared among the groups. RESULTS Both groups were comparable in terms of demographic profile (age and sex) and the ease of insertion was substantially improved without any difficulty in successful insertion in Group B patients (0 % vs. 16 %) and 20 % of Group A patients wanted more than one effective insertion attempt and 3 patients needed laryngoscopy for effective insertion after the insertion. Statistically lesser time was required for successful LMA insertion in Group B patients with use of laryngoscope and also required lesser volume of air to inflate the LMA cuff for a tight seal in an ideal position. CONCLUSIONS Laryngoscopic guided LMA insertion technique offers better final positioning of the classic LMA with a high first attempt success rate, which is highly desired by anaesthesiologists.