Annals of Intensive Care (Dec 2018)

Effect on comfort of administering bubble-humidified or dry oxygen: the Oxyrea non-inferiority randomized study

  • Laurent Poiroux,
  • Lise Piquilloud,
  • Valérie Seegers,
  • Cyril Le Roy,
  • Karine Colonval,
  • Carole Agasse,
  • Vanessa Zinzoni,
  • Vanessa Hodebert,
  • Alexandre Cambonie,
  • Josselin Saletes,
  • Irma Bourgeon,
  • François Beloncle,
  • Alain Mercat,
  • for the REVA Network

DOI
https://doi.org/10.1186/s13613-018-0472-9
Journal volume & issue
Vol. 8, no. 1
pp. 1 – 9

Abstract

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Abstract Background The clinical interest of using bubble humidification of oxygen remains controversial. This study was designed to further explore whether delivering dry oxygen instead of bubble-moistened oxygen had an impact on discomfort of ICU patients. Methods This randomized multicenter non-inferiority open trial included patients admitted in intensive care unit and receiving oxygen. Any patient receiving non-humidified oxygen (between 0 and 15 L/min) for less than 2 h could participate in the study. Randomization was stratified based on the flow rate at inclusion (less or more than 4 L/min). Discomfort was assessed 6–8 and 24 h after inclusion using a dedicated 15-item scale (quoted from 0 to 150). Results Three hundred and fifty-four ICU patients receiving non-humidified oxygen were randomized either in the humidified (HO) (n = 172), using bubble humidifiers, or in the non-humidified (NHO) (n = 182) arms. In modified intention-to-treat analysis at H6–H8, the 15-item score was 26.6 ± 19.4 and 29.8 ± 23.4 in the HO and NHO groups, respectively. The absolute difference between scores in both groups was 3.2 [90% CI 0.0; + 6.5] for a non-inferiority margin of 5.3, meaning that the non-inferiority analysis was not conclusive. This was also true for the subgroups of patients receiving either less or more than 4 L/min of oxygen. At H24, using NHO was not inferior compared to HO in the general population and in the subgroup of patients receiving 4 L/min or less of oxygen. However, for patients receiving more than 4 L/min, a post hoc superiority analysis suggested that patients receiving dry oxygen were less comfortable. Conclusions Oxygen therapy-related discomfort was low. Dry oxygen could not be demonstrated as non-inferior compared to bubble-moistened oxygen after 6–8 h of oxygen administration. At 24 h, dry oxygen was non-inferior compared to bubble-humidified oxygen for flows below 4 L/min.

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