Comparison of standard versus 90\xb0 rotation technique for LMA Flexible\u2122 insertion: a randomized controlled trial

Bon-Wook Koo,Ah-Young Oh,Jung-Won Hwang,Seong-Won Min,Hyo-Seok Na

doi:10.1186/s12871-019-0773-z

Abstract

BackgroundInsertion of a flexible laryngeal mask airway (LMA Flexible) is known to be more difficult than that of a conventional laryngeal mask airway. The 90° rotation technique can improve the success rate with a conventional laryngeal mask airway but its effect with the LMA Flexible remains unknown. We assessed whether the 90° rotation technique increased the first-attempt success rate of LMA Flexible insertion versus the standard technique.MethodsIn total, 129 female patients undergoing breast surgery were analyzed. The primary endpoint was success at the first attempt. The insertion time, number of trials, number of manipulations required, and oropharyngeal leak pressure were also evaluated. Heart rate and mean blood pressure were recorded 1 min before and 1 min after insertion. Blood staining on the LMA Flexible after removal and postoperative sore throat were checked.ResultsThe first-attempt success rates were comparable between the groups (93% vs. 98.3%, P = .20). The insertion time, number of trials and manipulations, hemodynamic variables, and complications, such as blood staining and sore throat, did not differ between the groups.ConclusionsThe 90° rotation technique is a good alternative to the standard technique for insertion of the LMA Flexible.Trial registrationClinicalTrials.gov (NCT03028896). It was registered retrospectively at Jan 19th, 2017.

Highlights

Insertion of a flexible laryngeal mask airway (LMA Flexible) is known to be more difficult than that of a conventional laryngeal mask airway
It is known that perioperative respiratory adverse events, such as laryngospasm, bronchospasm, sore throat, postoperative hoarse voice, and coughing, are decreased with the use of supraglottic airway compared to endotracheal tube [1,2,3]
mean arterial pressure (MAP) and heart rate 1 min before and after the insertion of the Laryngeal mask airway (LMA) did not differ between the groups

Summary

Introduction

Insertion of a flexible laryngeal mask airway (LMA Flexible) is known to be more difficult than that of a conventional laryngeal mask airway. The flexible laryngeal mask airway, LMA Flexible (Teleflex Co., Westmeath, Ireland), has a unique design, allowing the tube to be moved out of the surgical field without displacement of the cuff or loss of a seal. It allows the tube complete flexibility and resistance to compression, such that the head and neck can be turned without dislodging the mask. Some authors stated that it is more difficult to insert because the elasticity of its shaft makes it difficult to insert They proposed tools to improve insertion of the LMA Flexible, such as a modified Magill forcep, a stylet, the Bosworth introducer, and the spatula introducer [5,6,7,8].

Methods

Results

Discussion

Conclusion