Comparison of 2 cuff inflation methods before insertion of laryngeal mask airway for safe use without cuff manometer in children

Purpose

This prospective, randomized trial was conducted to establish whether the pediatric laryngeal mask airway (LMA) could be used without any concerns for abnormally high intra-cuff pressure when a cuff of the LMA was inflated with half the maximum recommended inflation volume or the resting volume before insertion.

Basic procedures

Eighty children 0 to 9 years of age and weighing of 5 to 30 kg scheduled for general anesthesia were included. Before insertion, the cuff of the LMA was filled with half the maximum recommended inflation volume in the Half volume group, or the resting volume by opening the pilot balloon valve to atmospheric pressure in the Resting volume group. After insertion of the LMA, intra-cuff pressure, oropharyngeal leak pressure, and leakage volume were investigated.

Major findings

The Half volume group showed lower mean intra-cuff pressure than the Resting volume group (49.6 ± 12.1 cm H₂O vs 58.1 ± 13.8 cm H₂O, P = .005). There was no difference in oropharyngeal leak pressure (22.1 ± 5.8 vs 21.7 ± 5.1 cm H₂O, P = .757) or leakage volume between the Half volume group and the Resting volume group (0.13 ± 0.13 ml/kg vs 0.11 ± 0.12 ml/kg, P = .494) under spontaneous respiration.

Conclusions

Both methods of the LMA cuff inflation before insertion provided an acceptable range of intra-cuff pressure with adequate pharyngeal sealing without any intervention after insertion.