The Effects of Nitrous Oxide-Oxygen Anaesthesia on Laryngeal Mask Airway Cuff Pressure, Positioning and Pharyngeal Morbidity: A Comparison of the LMA Classic~(TM) with the Ambu~R AuraOnce~(TM) Laryngeal

摘要

The aim of this study was to compare the effects of nitrous oxide-oxygen (N_2O/O_2) anaesthesia on the cuff pressure, LMA positioning and pharyngeal morbidity between LMA-Classic~(TM) and the disposable Ambu~R AuraOnce~(TM) Laryngeal Mask 60 patients underwent spontaneous breathing anaesthesia were randomized to receive either size 4 LMA-Classic~(TM) or size 4 Ambu~RLMA. The cuff was inflated to a pressure of 60 cmH_2O after insertion. Intracuff pressure measurements were measured every 10 min for 30 min. Fibreoptic position was determined using a scoring system. 24 hours after surgery, patients were questioned for sore throat, hoarseness of voice, and dysphagia.The demographic data were comparable in both groups. Over a 30min period, the intracuff pressure increased significantly in LMA-Classic~(TM) (p<0.001) and Ambu~RLMA (p,0.001), and there was a significant difference between the groups over time (p<0.001 by ANOVA). The fibreoptic view and post-op pharyngeal morbidity were similar in both groups.