Trainability of Cricoid Pressure Force Application: A Simulation-Based Study.

Background: Aspiration of gastric contents is a leading cause of airway management-related mortality during anesthesia practice. Cricoid pressure (CP) is widely used during rapid sequence induction to prevent aspiration. National guidelines for CP suggest a target force of 10 N before and 30 N after loss of consciousness. However, few studies have rigorously assessed whether clinicians can be trained to consistently achieve these levels of force. We hypothesized that clinicians can be trained effectively to deliver 10-30 N during application of CP.
Methods: Clinicians (attending anesthesiologist, anesthesiology residents, certified registered nurse anesthetists, or operating room nurses) applied CP on a Vernier force plate simulator with measurements taken at 4 time points over 60 seconds, 2 measurements before and 2 measurements after loss of consciousness. A successful cycle required all 4 time points to be within the target range (10 ± 5 and 30 ± 5 N, respectively). After baseline assessment (n = 100 clinicians), a subset of 40 participants volunteered for education on recommended force targets, underwent self-regulated practice, and then performed 30 1-minute cycles of high-frequency simulation analyzed by cumulative sum analysis to assess their change in performance.
Results: At baseline, 5 cycles (1.3% [confidence interval {CI}, 0.3%-2.50%]) out of 400 were successful. Performance improved after education and self-regulated practice (16% successful cycles [CI, 7.8%-25%]), and performance during the last 4 of 30 cycles was 45% (CI, 33%-58%). The odds of success increased over time (odds ratio, 1.1; P < .001). By cumulative sum analysis, however, no subject crossed the h0 line, indicating that no one achieved proficiency of the predefined target forces.
Conclusions: At baseline, performance was poor at achieving target forces specified by national guidelines. Simulation-based training improved the success rate, but no participant achieved the predefined threshold for proficiency.