Five sessions of Hyperbaric Oxygen for critically ill patients with COVID-19-induced ARDS: a randomised, open label, phase II trial.

BACKGROUND Few treatment options exist for patients with COVID-19-induced acute respiratory distress syndrome (ARDS). Data on the benefits and harms of hyperbaric oxygen treatment (HBOT) for this condition is limited. OBJECTIVE To evaluate benefits and harms of HBOT in patients with COVID-19 induced ARDS. METHODS In this open-label trial conducted at three hospitals in Sweden and Germany, patients with moderate to severe ARDS and at least two risk factors for unfavourable outcome, were randomly assigned (1:1) to medical oxygen 100%, 2·4 Atmospheres absolute (ATA), 80 minutes (HBOT) adjuvant to best practice or to best practice alone (Control). Randomisation was stratified by sex and site. The primary endpoint was ICU admission by Day 30. RESULTS Between June 4, 2020, and Dec 1, 2021, 34 subjects were randomised to HBOT (N=18) or Control (N=16). The trial was prematurely terminated for futility. There was no statistically significant difference in ICU admission, 5 (50%) in Control vs 13 (72%) in HBOT. OR 2·54 [95% CI 0·62-10·39], p=0·19. HARMS 102 adverse events (AEs) were recorded. 16 (94%) subjects in the HBOT group and 14 (93%) in the control group had at least one AE. Three serious adverse events (SAEs), were at least, possibly related to HBOT. All deaths were unlikely related to HBOT. CONCLUSIONS HBOT did not reduce ICU admission or mortality in patients with COVID-19-induced ARDS. The trial cannot conclude definitive benefits or harms. Treating COVID-19-induced ARDS with HBOT is feasible with a favourable harms profile. FUNDING Swedish Research Council, grant number KBF 2019-00446.