A randomised trial comparing a 4-stage to 2-stage teaching technique for laryngeal mask insertion

Abstract 

Objective

To compare the ‘4-stage’ teaching technique (demonstration, deconstruction, formulation, performance) with the traditional ‘2-stage’ teaching technique (deconstruction, performance) in laryngeal mask airway (LMA) insertion.

Methods

Using a prospective randomised study design, participants were taught LMA insertion on a manikin by either the ‘2-stage’ or ‘4-stage’ teaching method. Subjects were eligible if they had never inserted a LMA. Skill acquisition was assessed immediately following training, and skill retention assessed a number of weeks later. The primary outcome was LMA insertion on a manikin, with successful ventilation within 30s. Other outcomes included overall time to LMA insertion, and number of errors. Assessors were blinded to the teaching method used for each subject.

Results

A total of 120 participants were randomised between the two teaching groups (60 subjects in each group). Mean time to LMA insertion at acquisition was 39.7s for 2-stage and 34.7s for 4-stage (p>0.05), and proportion completing within 30s was 41.67% for 2-stage and 48.33% for the 4-stage teaching group (p>0.05). With skill retention assessment, mean time to LMA insertion was 44.3s for 2-stage and 42.5s for the 4-stage teaching group (p>0.05). Proportion completing task within 30s was 34.0% for 2-stage and 41.67% for 4-stage group (p>0.05). Overall, there was no significant difference found in skill acquisition or in skill retention between the 2 or 4-stage teaching method.

Conclusion

The 2-stage teaching technique is not statistically different to the 4-stage teaching method in efficacy of LMA insertion skill acquisition or retention.

Keywords: 4-Stage, 2-Stage, Laryngeal mask airway, LMA, Teaching, Skill