Difference in PaO2/FiO2 between high-flow nasal cannula and Venturi mask in hypoxemic COVID-19 patients

Ilenia Gatto; Emanuela Biagioni; Irene Coloretti; Serena Viappiani; Stefano Busani; Massimo Girardis

doi:10.1186/s44158-022-00051-w

Difference in PaO₂/FiO₂ between high-flow nasal cannula and Venturi mask in hypoxemic COVID-19 patients

J Anesth Analg Crit Care. 2022 May 24;2(1):23. doi: 10.1186/s44158-022-00051-w.

Authors

Ilenia Gatto¹, Emanuela Biagioni², Irene Coloretti², Serena Viappiani², Stefano Busani², Massimo Girardis²

Affiliations

¹ Anaesthesiology and Intensive Care Department, University Hospital of Modena, University of Modena and Reggio Emilia, 41125, Modena, Italy. ilenia.gatto@gmail.com.
² Anaesthesiology and Intensive Care Department, University Hospital of Modena, University of Modena and Reggio Emilia, 41125, Modena, Italy.

Abstract

The ratio between arterial blood partial pressure of oxygen and fraction of inspired oxygen (PaO₂/FiO₂) was largely used for grading and managing the respiratory failure in non-mechanically ventilated COVID-19. In these patients, the assessment of the true FiO₂ in the inspired mixture may be difficult with consequent inaccuracies in PaO₂/FiO₂ assessment. In 30 severe COVID-19 patients, we observed that PaO₂/FiO₂ values measured immediately before and after the transition from high-flow nasal cannula (HFNC) to one commercially available Venturi mask O₂ therapy were similar (bias mean value 0, standard deviation 23 mmHg). In COVID-19 patients recovering from respiratory failure, PaO₂/FiO₂ is not different whether measured with a commercially available Venturi mask or HFNC.

Keywords: COVID-19; HFNC; ICU; PaO2/FiO2.