The International Liaison Committee on Resuscitation regularly publishes a Consensus on Science with Treatment Recommendations but guidelines can nevertheless differ when knowledge gaps persist. In case of pediatric cardiac arrest, the American Heart Association recommends following the adult resuscitation sequence i.e., starting with chest compressions. Conversely, the European Resuscitation Council advocates the delivery of 5 initial rescue breaths before starting chest compressions. Carrying out a randomized trial in children in cardiac arrest to assess the impact of these strategies would prove particularly challenging and ethical concerns may prevent such a trial from being performed. This will be a superiority, cross-over randomized trial whose goal is to determine the impact of these 2 resuscitation sequences on alveolar ventilation in a pediatric model of cardiac arrest. While not definitive, its results could help fill part of the current knowledge gap.

This will be a randomized, cross-over, superiority trial. The intention is to carry it out on the first Prehospital Research Day which will be held on September 1st, 2022, i.e., on a single date. This event will take place at a single center in Neuchâtel, Switzerland. If the intended sample size cannot be reached on this day, or if technical issues prevent data from being collected or extracted, other study sites will be considered.

Participant recruitment will be conducted online. A web-based platform based on the Joomla 4 (Open Source Matters, New York, USA) content management system will be specifically created for the purpose of this study. The Event Booking 4 component (Joomdonation, Hanoi, Vietnam) will be used to create 20-minute time slots. Demographic data will be collected during the registration process. Consent will be gathered electronically.

Since the objective of this study is to assess the impact of basic airway management and ventilation maneuvers only, there will be no stratification since all the professionals eligible for inclusion should be equally proficient in basic airway management. Furthermore, all participants will be able to practice this skill on a manikin identical to the one used to perform the study. This training will not be time limited and will take place immediately before the sequence during which data will be collected.

An investigator who will not be present during the resuscitation sequences will create stacks of opaque, sealed envelopes. Each stack of 10 envelopes will contain an equal number of American Heart Association (AHA) and European Resuscitation Council (ERC) allocations. Randomization will take place after the training session. The first leader will choose and open one of the envelopes placed on a table in random order by one of the on-site investigators. This will determine the resuscitation sequence which will first be used by the team.

A SimBaby manikin (Laerdal SimBaby, Laerdal Medical, Stavanger, Norway) will be used in this study. The SimBaby is a realistic manikin representing a 9-month-old infant. The manikin weighs 4.9 kg and is 71 cm tall. It is accompanied with a dedicated multiparameter monitor/defibrillator. Back compensation, using a folded blanket, will be applied. An appropriately sized bag-valve-mask (BVM) device will be ready for use next to the manikin. The defibrillation pads will be already attached.

Participants will be told that they are facing a 9-month old infant who suddenly collapsed. They will be told that there is no foreign body airway obstruction and that the infant is in cardiac arrest.

Each team of two people will perform 4 resuscitation sequences of one minute each. Each participant will act as leader for two successive resuscitation sequences, the first of which will be carried out according to the random allocation described above. The scenario will be identical for all resuscitation sequences. After completing these two sequences, participants will exchange their roles, and the new leader will pick up another opaque, sealed envelope. The content of this envelope will determine the resuscitation sequence the newly appointed leader will have to use first.

The timer will start (T0) at the moment when the first action (chest compression or ventilation) will have been performed and will stop exactly after 60 seconds.

It will not be possible to blind the participants or the on-site investigators as to the design of the study or even to the allocation of the participants. Nevertheless, the outcomes will not be communicated to the participant. In addition, data extraction will be fully automated and the statistician will not know the identity of the participants or the sequence they were allocated to.

Inclusion Criteria:

• Being issued from one of the following profession: Emergency medical technicians (EMTs), paramedics, nurses and physicians

Exclusion Criteria:

• Being member of the study team

Anonymized data set will be made publicly available on the Digital Commons Data repository

Data will be available after publication of the results

Publicly available

From enrollment until end of study (up to 2 hours)

No adverse event could occurr because it was a simulation study.

Simulation study (no risk).

Data extraction will be fully automated and the statistician will not know the identity of the participants or the sequence they were allocated to.