This randomized controlled trial aims to determine if the stress response and performance of trainees who are observers in simulation training is similar to trainees who are actively participating in simulation training in the 'hotseat' during 3 consecutive simulation sessions.

We hypothesize that trainees experience less stress when they are observers in the first 2 simulation sessions. However, when they are placed in the 'hotseat' during the third session, their stress response, as well as their performance, will be similar to trainees who spend all 3 simulation sessions in the 'hotseat'.

Background: High fidelity simulation-based training (SBT) using sophisticated manikins instead of real patients for medical teaching is now commonly practiced worldwide. We previously showed that SBT causes significant stress in the trainees, as evidenced by a rise in their heart rate and salivary cortisol(; and that repeated exposure to SBT was associated with the same level of stress, despite performance improving. From our studies, participants in the 'hot-seat' actively managing the clinical crisis experience the highest levels of stress but benefit the most from the learning experience. However, the stress experienced by observers (who are in the same room but not actively managing the crisis) and their learning outcomes have not been studied.

Objectives: We aim to determine: 1) If observers of SBT experience less stress when compared to the trainees in the 'hot-seat' and; 2) if trainees who were observers in prior SBT sessions perform as well as trainees who were in the 'hot-seat' during subsequent SBT sessions.

Methodology: Thirty-six trainee anaesthetists are randomized into 2 groups to undergo three SBT scenarios. 18 Trainees randomized to the Observer group will first undergo two SBT scenarios as observers followed by a third session in the 'hot-seat'. 18 Trainees in the Control group will undergo all 3 sessions in the 'hot seat'. For each session, stress response is measured by salivary cortisol and amylase while performance is measured using the Anaesthetists Non Technical Skills (ANTS) score.

Clinical Significance: If we find that trainees who are observers of the first 2 SBT scenarios experience less stress than the 'hot-seat' trainees but yet achieve similar level of performance during the third SBT session, we can potentially make SBT less stressful and reduce the total number of simulation required, thus improving the efficiency of simulation training.

Inclusion Criteria:

• Anaesthesia residents in their 2nd or 3rd year of training

Exclusion Criteria:

• Hypertension
• Cardiac disease
• Endocrine disorder
• Use of beta-blockers
• Recent stressful or traumatic life events
• Pregnancy