Hyperbaric Versus Normobaric Oxygen Therapy for COVID-19 Patients
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ClinicalTrials.gov Identifier: NCT04500626 |
Recruitment Status :
Recruiting
First Posted : August 5, 2020
Last Update Posted : November 1, 2021
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At least 1 in 6 COVID-19 patients admitted to hospital to receive extra oxygen will die of complications. In patients with COVID-19, invasive treatment such as mechanical ventilation (e.g. breathing with a machine) is associated with a 50% increased risk of death. Invasive treatments use a lot of healthcare resources in intensive care units and may lead to further deaths if patients do not have access to care.
The investigators aim to improve outcomes for COVID-19 patients by implementing hyperbaric oxygen therapy (HBOT). HBOT allows patients to breathe 100% oxygen in a special chamber at a pressure higher than sea level. It is approved by Health Canada for 14 conditions. HBOT is safe when administered by experienced teams.
There are two main causes of death in severe COVID-19 respiratory infections: (i) a decreased diffusion of oxygen from the lungs to the blood and (ii) an increased inflammatory response (also called a "cytokine storm"). HBOT leads to increased oxygen level in blood, has strong anti-inflammatory effects, and may destroy the virus responsible for COVID-19 disease. The initial experience with HBOT and COVID-19 from China, France and the United States is promising in that it prevents further worsening of the condition and need for intensive care.
The investigators propose to test the effectiveness of HBOT for COVID-19 patients who are admitted to hospital to receive extra oxygen. Using the most rigorous and innovative research methods, this Canadian-led international study will operate at 5 centers across 3 countries (Canada: Ottawa, Toronto, Edmonton; Switzerland: Geneva; UK: Rugby/London). The investigators anticipate that when treated by HBOT, COVID-19 patients needing extra oxygen to breathe will see significant health improvements as well as a decrease in complications, inflammation in the blood, need for invasive care, death, and cost of care.
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Covid19 | Drug: Oxygen | Phase 2 Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 234 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Single (Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | Multicentre Randomized Controlled Trial of Hyperbaric Versus Normobaric Oxygen Therapy for COVID-19 Patients |
Actual Study Start Date : | April 15, 2021 |
Estimated Primary Completion Date : | August 2022 |
Estimated Study Completion Date : | August 2022 |

Arm | Intervention/treatment |
---|---|
Experimental: HBOT
These patients will receive hyperbaric oxygen therapy (HBOT) in addition to usual treatment for COVID-19. HBOT sessions will be 75 minutes in length at a pressure of 2.0 ATA.
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Drug: Oxygen
Hyperbaric oxygen therapy delivered in a monoplace or multi-place chamber. Supervised by a hyperbaric oxygen therapy physician and a chamber operator. |
No Intervention: Control
These patients will receive usual treatment for COVID-19, including oxygenation at normal atmospheric pressure (normobaric oxygenation).
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- 7-level COVID Ordinal Outcome Scale [ Time Frame: Measured on Day 7 ]7-level scale based on patient's current status and need for oxygenation, also ability to resume normal activities (at higher levels). Range is 1-7. Higher number indicates better clinical outcome.
- Length of hospital stay [ Time Frame: Duration of study (to Day 28) ]Measured in days
- Days with oxygen supplementation [ Time Frame: Duration of study (to Day 28) ]Number of days with oxygen supplementation
- Daily oxygen flow values required to obtain saturation values ≥90%, [ Time Frame: Duration of study (to Day 28) ]Measured in L/min
- ICU admission [ Time Frame: Duration of study (to Day 28) ]Yes/No
- ICU length of stay [ Time Frame: Duration of study (to Day 28) ]Measured in days, if applicable
- Days on invasive mechanical ventilation or high flow oxygenation [ Time Frame: Duration of study (to Day 28) ]Number of days on ventilator
- Major arterial and venous thrombotic events [ Time Frame: Duration of study (to Day 28) ]e.g. stroke, pulmonary embolism, deep vein thrombosis
- Sleep quality [ Time Frame: Duration of study (to Day 28) ]Sleep Quality Scale, measured from 0 to 10. Higher number indicates worse sleep quality: 0 = "best possible sleep", 10 = "worst possible sleep". Capelleri et. al; Health and Quality of Life Outcomes 2009: 7:54
- Fatigue [ Time Frame: Duration of study (to Day 28) ]Single-Item Fatigue Report Mark, measured from 1 to 10. Higher number indicates worse fatigue: 1 = "not at all", 10 = "extremely". van Hooff et al; J Occup Health 2007; 49:224-234.
- 7-level COVID Ordinal Outcome Scale [ Time Frame: Measured on Day 28 ]Same scale as the primary outcome; different timing as a secondary outcome. Range is 1-7. Higher number indicates better clinical outcome.
- Mortality [ Time Frame: Duration of study (to Day 28) ]Number of deaths
- Incidence of any adverse events related to HBOT [ Time Frame: Duration of study (to Day 28) ]Number of adverse events

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Male or non-pregnant female patients
- Age ≥18 years
- Confirmed COVID-19 positive by RT-PCR or another validated method
- Diagnosed with pneumonia requiring 21%<FIO2≤100% to maintain saturation by pulse oximetry (SpO2) ≥90%
- Able and willing to comply with study procedures and follow-up examinations contained within the written consent form
Exclusion Criteria:
- Patient clinical status felt to be incompatible with HBOT, e.g. respiratory failure requiring mechanical ventilation
- Pregnancy, determined by a serum or urine test
- Hemodynamic instability requiring vasopressors
- Inability to maintain a sitting position during treatment
- Inability to effectively understand and communicate with the hyperbaric operator, or to give consent
- Inability to spontaneously equalize ears and refusal of myringotomies
- Contraindications to HBOT (e.g. pneumothorax)

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04500626
Contact: Sylvain Boet, MD, PhD | 613-737-8899 ext 78187 | sboet@toh.ca | |
Contact: Joseph Burns, MSc | 613-798-5555 ext 14775 | josburns@ohri.ca |
Canada, Ontario | |
The Ottawa Hospital | Not yet recruiting |
Ottawa, Ontario, Canada, K1Y4E9 | |
Contact: Sylvain Boet, MD, PhD 6137985555 ext 78187 sboet@toh.on.ca | |
Contact: Joseph Burns, MSc 613-798-5555 ext 14775 josburns@ohri.ca | |
Rouge Valley Hyperbaric Medical Centre | Recruiting |
Scarborough, Ontario, Canada, M1E 5E9 | |
Contact: Rita Katznelson, MD rita.katznelson@uhn.ca | |
Contact: Research Coordinator research@centenarypainclinic.ca | |
Principal Investigator: Rita Katznelson, MD |
Principal Investigator: | Sylvain Boet, MD, PhD | The Ottawa Hospital |
Responsible Party: | Ottawa Hospital Research Institute |
ClinicalTrials.gov Identifier: | NCT04500626 |
Other Study ID Numbers: |
OHRI-HBOT-001 |
First Posted: | August 5, 2020 Key Record Dates |
Last Update Posted: | November 1, 2021 |
Last Verified: | October 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
Hyperbaric oxygen therapy |
COVID-19 Respiratory Tract Infections Infections Pneumonia, Viral Pneumonia Virus Diseases |
Coronavirus Infections Coronaviridae Infections Nidovirales Infections RNA Virus Infections Lung Diseases Respiratory Tract Diseases |