A randomised controlled trial comparing two insertion techniques for the Laryngeal Mask Airway Flexible™ in patients undergoing dental surgery.

The Laryngeal Mask Airway Flexible™ (LMA Flexible) has been widely utilised for dental, ophthalmology and otorhinolaryngology-related procedures. Our study evaluates two different techniques of inserting the LMA Flexible for patients undergoing day-case dental surgery. One hundred and eight patients were randomly assigned into two groups based on the LMA Flexible insertion technique--either laryngoscopy-guided (n=54) or digital manipulation (standard technique; n=54). Patient and airway characteristics were recorded before induction of anaesthesia. The primary outcome was success rate at first insertion. Other outcomes assessed included fibreoptic assessment of laryngeal mask airway placement, haemodynamic changes, need for airway adjustment during surgery and sore throat. The success rate of insertion on the first attempt was higher for the laryngoscopy-assisted technique compared with the standard technique (96.3% vs 81.5%, respectively, p<0.05). Fibreoptic assessment showed that the former group had better placement of the laryngeal mask airway than the latter (59.3% vs 37% p<0.05). There were no significant differences between the two groups for haemodynamic changes. Sore throat was more common in the group with the standard technique (35.2% vs 16.7%, p<0.05). Our study suggests the use of the laryngoscope to guide insertion of the LMA Flexible for dental surgery is a better option compared with the standard technique of digital manipulation.