Author contributions

Pierre-Henri Moury, Flora Greco, and Pierre Albaladejo designed the study; Pierre-Henri Moury, Valentin Pasquier, Flora Greco, Jean-Lionel Arvieux, Silvia Alves-Macedo, Marion Richard, and Myriam Casez-Brasseur enrolled the patients; Pierre-Henri Moury, Jean-Lionel Arvieux, Silvia Alves-Macedo, Damien Bedague, Michel Durand, and Marion Richard conducted the study; Kristina Skaare and Jean-Luc Bosson analyzed the data; Pierre-Henri Moury, Valentin Pasquier, Jean-Luc Bosson, and Pierre Albaladejo analyzed all the data; Pierre-Henri Moury and Valentin Pasquier interpreted the results; Pierre-Henri Moury and Valentin Pasquier drafted the manuscript; all authors had full access to all of the study data, contributed to drafting of the manuscript or critically revised it for important intellectual content, and took responsibility for the integrity of the data and the accuracy of the data analysis.

Acknowledgements

The authors would like to thank l’école d’infirmier anesthésiste of the CHU Grenoble Alpes, the nurse anesthetists, the anesthetists, and the intensivists of the cardiovascular and thoracic unit. The authors would like to thank the neurosurgery anesthesia and intensive care unit teams for their involvement and independent assessment in the blinded analysis: Drs Perrine Boucheix, Lara Puthon, Marie-Cécile Fèvre, and Clotilde Schilte.

Disclosures

There are no conflicts of interest to disclose related to the subject of the article.

Funding statement

This study was supported by an institutional grant from CHU Grenoble Alpes. The foundation Agiradom provided masks and the respirator. Alpha2® (Lyon, France) provided the CO2 analysis.

Prior conference presentations

The abstract of the article was accepted for presentation at the 2020 congress of the Société Française d'Anesthésie-Réanimation (24–26 Spetember 2020, Paris, France).

Editorial responsibility

This submission was handled by Dr. Philip M. Jones, Deputy Editor-in-Chief, Canadian Journal of Anesthesia/Journal canadien d’anesthésie.