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Published on: May 4, 2021
Hyperbaric oxygen as an adjuvant treatment for patients with COVID-19 severe hypoxaemia: a randomised controlled
Mariana Cannellotto1, Mariano Duarte2,3, Guillermo Keller4,5,6
1Research Department, Argentine Association of Hyperbaric Medicine and Research (AAMHEI), Buenos Aires, Argentina.
Background:
Hyperbaric oxygen (HBO2) therapy has been proposed to treat hypoxaemia and reduce inflammation in COVID-19. Our objective was to analyse safety and efficacy of HBO2 in treatment of hypoxaemia in patients with COVID-19 and evaluate time to hypoxaemia correction.
Methods:
This was a multicentre, open-label randomised controlled trial conducted in Buenos Aires, Argentina, between July and November 2020. Patients with COVID-19 and severe hypoxaemia (SpO2 ≤90% despite oxygen supplementation) were assigned to receive either HBO2 treatment or the standard treatment for respiratory symptoms for 7 days. HBO2 treatment was planned for ≥5 sessions (1 /day) for 90 min at 1.45 atmosphere absolute (ATA). Outcomes were time to normalise oxygen requirement to SpO2 ≥93%, need for mechanical respiratory assistance, development of acute respiratory distress syndrome and mortality within 30 days. A sample size of 80 patients was estimated, with a planned interim analysis after determining outcomes on 50% of patients.
Results:
The trial was stopped after the interim analysis. 40 patients were randomised, 20 in each group, age was 55.2±9.2 years. At admission, frequent symptoms were dyspnoea, fever and odynophagia; SpO2 was 85.1%±4.3% for the whole group. Patients in the treatment group received an average of 6.2±1.2 HBO2 sessions. Time to correct hypoxaemia was shorter in treatment group versus control group; median 3 days (IQR 1.0-4.5) versus median 9 days (IQR 5.5-12.5), respectively (p<0.010). OR for recovery from hypoxaemia in the HBO2 group at day 3 compared with the control group was 23.2 (95% CI 1.6 to 329.6; p=0.001) Treatment had no statistically significant effect on acute respiratory distress syndrome, mechanical ventilation or death within 30 days after admission.
Conclusion:
Our findings support the safety and efficacy of HBO2 in the treatment of COVID-19 and severe hypoxaemia.
Trial Registration Number:
NCT04477954.
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