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Published on: February 28, 2012
Effect of Different Insertion Methods on LMA Protector-Related Complications: A Prospective Randomized Double-Blind
Shu-Jie Liu1, Si-Yi Xiong1,2, Lu Yu1
1Department of Anesthesiology (Qunli Campus), The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province.
Objective:
The authors compared the effect of 2 insertion methods, namely the conventional laryngeal mask airway (LMA) insertion and the index finger-assisted LMA insertion, on the incidence of complications associated with LMA Protector insertion.
Methods:
The authors enrolled 300 patients, who underwent painless bronchoscopy. The patients ranged in age between 18 and 75 and were classified as American Society of Anesthesiologists grade I to III. They were randomly divided into 2 groups: a control group of 150 patients and an assisted group comprising 150 patients. LMA was inserted using the conventional and index finger-assisted insertion methods in both groups, respectively. The primary outcome was postoperative complications, such as oral mucosal injury and pharyngeal pain. Secondary outcomes included the success rate of first-time insertion, the incidence rate of inverse folding of LMA tips, oropharyngeal leak pressure (OLP), and other postoperative complications.
Results:
Compared with the conventional LMA insertion method, index finger-assisted LMA insertion can significantly reduce the incidence rate of oral mucosal injury and pharyngeal pain, with fewer insertion failures. There was a statistically significant difference between the 2 groups in the visual field grading before adjustment for LMA alignment (P<0.0001). The conventional insertion method increased the likelihood of inverse folding of LMA tips. When the conventional insertion method was utilized, there was a significant difference in airway pressure and tidal volume before and after alignment under a fiberoptic bronchoscope (P<0.0001), but no significant difference in visual field grading and respiratory mechanics-related indicators.
Conclusions:
Index finger-assisted insertion can significantly reduce the incidence rate of LMA Protector-related complications and inverse folding of LMA tips.

