The influence of head and neck position on the oropharyngeal leak pressure of LMA Unique ? and I-GEL?

Objecitve: The primary aim was to compare the oropharyngeal leak pressure of LMA Unique and I-gel in different positions of the head and neck. As a secondary aim, insertion time, ease of insertion, hemodynamic effects and postoperative airway morbidity were compared.Material and Methods: A total of 103 patients of ASA group I-II, aged 18-65 years, were included in this prospective, randomized, double-blind study. Patients were randomly assigned into two groups: Group U (LMA Unique) and Group I (I-gel). After insertion of the supraglottic airway device; time to insertion, success rate at the first attempt and ease of insertion were recorded. Following insertion, the oropharyneal leak pressure was measured with the head of the patients in neutral, extension and right rotation position.Results: The success of the first placement, insertion time, ease of insertion, hemodynamic data, and postoperative sore throat were not significantly different between the groups (p>0.05). Oropharyngeal leak pressures (OLP) for the Group U in different head and neck positions were 25,06 / 22,28 / 27,30 cmH20 in neutral, extension and, right rotation positions, respectively. The same measurements for Group I in the neutral, extension and right rotation position were 28,24 / 26,62 / 26,04 cmH20, respectively. The difference between the two groups was significant in neutral (p=0.04) and extension (p=0.02) positions. In the I-gel group, higher oropharyngeal leak pressures were reached in these positions.Conclusion: In conclusion, both supraglottic airway devices were found similar in terms of airway safety during surgical procedures when given various head and neck positions. However, I-gel was superior in terms of OLP in neutral and extension positions (p <0.05).Key Words: I-gel, oropharyngeal leak pressure, head position