Safety of healthcare professionals working in high-risk environments is of upmost importance. Personal protective equipment (PPE) may affect the performance of individuals and teams by altering their senses, manual skills and ability to communicate. Current guidelines offer flexibility in terms of which specific PPE components can safely be used. Yet, in some organisations, healthcare workers become used to using PPE well above the recommended standards (termed further in text as super-safe setup, SSS). Impact of this PPE policy on team performance and in turn to patient safety is unknown. The investigators hypothesise that SSS, as compared to WHO PPE standard, would negatively impact team performance and patient outcomes in a simulated crisis scenario.

Safety of healthcare professionals working in high-risk environments is of upmost importance. Personal protective equipment (PPE) may affect the performance of individuals and teams by altering their senses, manual skills and ability to communicate. Current guidelines (WHO, UK, ECDC) offer flexibility in terms of which specific PPE components can safely be used. Yet, in some organisations, healthcare workers become used to using PPE well above the recommended standards (termed further in text as super-safe setup, SSS). Impact of this PPE policy on team performance and in turn to patient safety is unknown. The investigators hypothesise that SSS, as compared to WHO PPE standard, would negatively impact team performance and patient outcomes in a simulated crisis scenario.

Methods Design: prospective, open, randomised, controlled, parallel group trial, fully compliant with CONSORT guidelines with extension for simulation studies.

Study subjects: doctors and nurses routinely working in intensive care, written prospective informed consent Setting: High-fidelity simulation centre, Third Faculty of Medicine, Charles University in Prague

PPE tested

• WHO group (CONTROL): uses polycarbonate safety spectacles, fluid-resistant (Type IIR) surgical mask and disposable surgical gown. One pair of gloves. No head or foot cover.
• SSS group: Uses surgical cap, FFP3 respirator covered by surgical mask, face shield, whole-body suit (Tyvec), 3 pairs of gloves typed to suit sleeves and disposable foot cover

Study procedures: Teams consisting of one doctor and two nurses will be recruited. The purpose of the study will be explained to them as a part of consent procedure, but details of evaluation and scenarios will remain undisclosed. All team members will obtain standardized educational materials focused on the solution of airway management and non-shockable rhythm of sudden circulatory arrest in a critically ill patient.

• Introduction to simulation centre and baseline team performance measurement: On the study day the teams will undergo a standardised introduction to simulation centre and perform a mock scenario without PPE apart from gloves and simple surgical masks. The same parameters will be measured for mock scenario as for the test scenario.
• Test scenario: This will be a COVID-19 patient on mechanical ventilator who suddenly loses airways and develops profound hypoxia progressing to cardiac arrest. Team will be wearing PPE according to their study group allocation at the beginning of the scenario.

Outcomes:

• Primary outcome: Non-technical team performance measured as TEAM score and adjusted to baseline team performance

• Secondary outcomes: Quality of CPR and work according to guidelines

• Exploratory qualitative objective: physiological functions of team members and self-reported confidence defined on visual analogue scale

Outcome assessment methods: Performance indices will be observed by two independent, trained assessors. Both assessors will have access to video recordings of scenarios and software recordings. The final score will be an arithmetic mean of the scores of two observers. Inter-rater variability will be calculated and reported.

Sample size calculation and statistics: According to [ref] the TEAM performance score was 3.3±0.7 (mean±standard deviation). Therefore, n=22 (i.e. 11 teams per group) gives 80% probability of detecting at p<0.05 (two sided) 25% difference of TEAM scores between groups. Primary outcome will be calculated by two sided Student t-test. Time-to-event outcomes will be compared using Kaplan-Meier curves and Wilcoxon test.

Dissemination plan and implementation: Data will be published in a peer-reviewed journal. The results have the potential to influence hospital hygiene policies as well as choices made by individual healthcare professionals.

Inclusion Criteria:

• Emergency Medicine (EM) and Anesthesiology and Critical Care (ACC) physicians
• Emergency Medicine (EM) and Anesthesiology and Critical Care (ACC) nurses
• Preparation and study of sent educational materials
• Fulfillment of the whole complete simulation

Exclusion Criteria:

• Not giving or withdrawal of the informed consent
• Not willing to participate
• Incomplete data acqusition

All data, forms, consents and protocols will be provided on reasonable request by investigators.

Blinding of participants and researchers involved in the experiment is not possible. Only the outcome assessor and data analyst is kept blinded to the allocation of subjects.