Enhancing emergency front-of-neck airway training: a mixed methods study on the impact of external noise and startle stressors: Stress and Startle

Introduction: Our aim was to investigate whether emergency front-of-neck airway training utilising low-fidelity manikins in a ‘tea-trolley’ format could be improved by the incorporation of stress inoculation training. This would be an important advance as clinicians report that cognitive overload impairs performance during real emergencies. We hypothesised that environmental noise and simulated blood splatter would result in a heightened stress experience. Methods: Thirteen anaesthetic residents completed the study, performing emergency front-of-neck access first under non-stressed conditions and later with the addition of noise and startle stressors. The primary outcome was a change in salivary cortisol, measured before and after each training session. Secondary outcomes included participant proficiency; time to perform the procedure; and perceived stress and utility of the training. Semi-structured interviews explored participant perceptions of the training. Results: Environmental noise and simulated blood splatter resulted in a quantitatively and qualitatively heightened stressful experience for the participants in paired comparisons. There was no significant change in median (IQR [range]) salivary cortisol levels after participants completed the non-stressed training: 6.4 (4.3–8.1 [3.3–16.2]) nmol.l ^-1 vs. 9.2 (5.8–11.3 [3.8–14.1]) nmol.l ^-1, respectively (p = 0.133). There were, however, significant changes following stressed training: 4.9 (4.3–11.6 [1.1–11.6]) mol.l ^-1 vs. 9.2 (8.0–12.1 [4.4–20.1]) nmol.l ^-1, respectively (p = 0.005). Participants' semi-structured interviews and questionnaire results evidenced that the adaptations created a more stressful yet valuable training experience. Discussion: Environmental noise and simulated blood splatter increased participant stress. Participants performed emergency front-of-neck access equally well in both sessions, suggesting this technical skill is stored in their stress-resistant long-term memory. These relatively low-cost adaptations could enhance emergency front-of-neck airway tea-trolley training by facilitating stress inoculation training and so better prepare clinicians for real-world emergencies.