Randomized Comparative Study Between Classic Laryngeal Mask Airway and I Gel Airway in Obese Patients Having BMI 35-40 During Elective Non Abdominal Surgery.

Because of the advantages of supraglottic devices over the conventional endotracheal intubation, they are now widely used in ventilation. The classic LMA is a first generation simple airway tube consists of two parts, the tube and the cuffed peri-laryngeal sealer mask which is designed to provide an oval seal around the laryngeal inlet. It is made of medical grade silicone; it can be autoclaved and reused many times. I gel is a new type of laryngeal mask and doesn't have an inflatable cuff. Because of its thermoplastic elastomer structure, it exactly adapts to the supraglottic tissue by binding with body temperature, thus minimising air leakage. The aim of this study is to compare between cLMA and I gel regarding insertion success rate, the time of insertion, leaking pressure, assessment of position by fiber optic, hemodynamic, Spo2 for each device during insertion and maintenance of general anaesthesia and postoperative complications in obese patients. This study was conducted in Kasr Al-Ainy Teaching Hospital, after obtaining approval from Kasr Al-Ainy hospital research ethical committee, written informed consents were taken from 50 patients, all of whom completed this study. Patients were randomly allocated into 2 equal groups, 25 each, according to the inclusion and exclusion criteria.

• GA (n=25) in which classic laryngeal mask was used for ventilation.
• GB (n=25) in which I gel was used for ventilation. In our study the median insertion time was in I gel lesser than cLMA (9 s vs 10 s) respectively that was statistically significant but clinically insignificance. Higher leaking pressure was in I gel group (25cmh2o vs 18cmh2o) than cLMA group that was statistically significant. Our main finding in the study was that both supraglottic airway devices; the classic LMA and the I GEL mask are satisfactory devices providing high airway leaking pressures. Although both devices provide high airway leaking pressures, our study revealed that the I gel mask provides a better seal with the glottic aperture and shorter time of insertion than cLMA. Both devices showed also effective ventilation, more hemodynamic stability and no episode of hypoxia with minimal postoperative complications.

Inclusion criteria

• Adult healthy ASA II patients
• both genders
• BMI 35-40
• aged 18 - 60 years
• Mallampati grade I, II with airway score < 4 according to El Ganzouri score during elective non abdominal surgery ≤ 2hour e.g diagnostic arthroscopy, hysteroscopy and cataract

Exclusion criteria

• ASA class III or IV
• Age >60 years or <18 years,
• people with hypertension, diabetes, pregnancy, gastro oesophageal reflux disease, cardiovascular ,renal disease4. difficult mask ventilation , obstructive sleep apnea ,any position rather than supine , airway score ≥ 4 according to El Ganzouri score

• any form of sore throat ,patients allergic to any drugs used in the study 6. PCV mode if measured tidal volume was lesser than 6 ml/kg it will be excluded.