Assessment of the most effective method of teaching cricoid pressure force

Cricoid pressure is used to reduce the risk of aspiration during rapid sequence induction. The recommended force applied to the cricoid is 10-20 newtons (N; 1.020-1.040 kg) on awake patients and 30-40N (3.060-4.080 kg) on anaesthetised patients. However clinically, it is difficult to estimate the required force. We assessed the effectiveness of 3 recommended teaching methods on the ability to apply the correct force using an airway model that simulated “awake” and “anaesthetised” patients. Thirty nurses and doctors from two hospitals and with clinical experience applying cricoid pressure were included. Measurements of baseline force for “awake” and “anaesthetised” patients were obtained from all participants using measuring scales. Participants were blinded to the force applied. Participants were taught one of three different techniques: biofeedback, nose and syringe. Post-teaching, blinded force measurements were repeated. Data analysis was performed using a linear mixed model and marginal prediction models of applied force reported. For “awake” patients, nose method forces were within the recommended range (mean 14.6N, 95%CI 9.7-19.4). The biofeedback method led to predicted forces at the upper limit of recommended (21.6N, 95%CI 16.7-26.4) and the syringe method forces were greater than recommended (29.0N, 95%CI 23.9-34.0). For “anaesthetised” patients, nose method forces were less than recommended (26.3N, 95%CI 21.6-31.1), the biofeedback method led to predicted forces within range (33.4N, 28.4-38.3) and syringe method forces were above those recommended (40.8N, 95%CI 35.8-45.8). The biofeedback technique is the most effective method for teaching the application of recommended cricoid pressure force for both awake and anaesthetised patients.