Cricoid pressure: a simple, yet effective biofeedback trainer

Background and objective: Only regular training of anaesthetic personnel ensures safe and reliable application of cricoid pressure during rapid sequence induction of anaesthesia. Previously described training devices are either complicated, too expensive and usually unavailable, or they are very simple and do not correctly simulate the process of applying cricoid force. We designed and tested a cricoid pressure trainer with real-time display of applied force. The device is easy to assemble at relatively little cost with material widely available. It allows effective biofeedback training of the force required during the Sellick manoeuvre and can be used for routine staff assessment. Methods: Thirty-six anaesthesia assistants were assessed for their correct application of cricoid pressure. Previous training in, and knowledge of, applying cricoid pressure was first evaluated by a questionnaire. We designed a model for testing the application of cricoid force. Pre-training cricoid forces were obtained by asking the subjects to apply 'awake' (10 N = 1.020 kg) and 'asleep'(30 N = 3.060 kg) cricoid pressure on our model while blinded to the actual pressure produced. The volunteer was then trained to apply correct pressure employing real-time biofeedback. Post-training values were later determined with the subject again blinded to the actual applied pressure. Results: Post-training performance showed significant improvement in the application of the correct cricoid force (P < 0.0005). Only 8176 (3/36) of subjects applied incorrect 'awake' cricoid pressure after training vs. 5696, (20/36) before training. All participants applied correct 'asleep' cricoid pressure after training vs. 72,70 (26/36) failing before training. Conclusions: Our b1ofeedback cricold pressure trainer is effective in the assessment and training of correct cricoid pressure application by anaesthetic personnel.