for people ages 18-65 (full criteria)
study started
estimated completion



This is a pilot study in 24 subjects where half will be randomized to 10 treatments with hyperbaric oxygen (HBO). It will primarily study pulmonary sequelae with imaging and physiological measurements (low dose chest computer tomography (CT), Ventilation/perfusion with magnetic resonance imaging (VA/Q MRI), cardiopulmonary exercise testing with pulse oximetry (SpO2) and spirometry including diffusion capacity for carbon monoxide (DLCO). The target patient group will be previously healthy whom have had covid-19 with lingering symptoms past 12 weeks of recovery from the acute phase.

Official Title

Hyperbaric Oxygen Therapy for Long COVID Patients With Pulmonary Sequela - Pilot Study


Long COVID or Post-Acute Sequelae of SARS-CoV-2 infection (PASC) is current terms for patients demonstrating fatigue, chest pain, exertion malaise, dyspnea, cognitive dysfunction, and headaches, just to name a few symptoms that can last more than 12-weeks after the initial infection of SARS-CoV-2. Pulmonary symptoms of dyspnea and exercise intolerance may be due to pulmonary gas exchange derangement, which could be from hypoxic pulmonary vasoconstriction (HPV) inhibition due to lingering inflammatory processes. Hyperbaric oxygen (HBO) has known anti-inflammatory effects, shown in multiple organ systems, and recently reported in case studies to improve outcomes of acute COVID-19 pneumonitis. If there is pulmonary inflammation it is possible that HBO can improve pulmonary gas exchange by restoring HPV. To test this hypothesis, we plan to perform a mechanistic study on V̇A/Q̇ matching in Long COVID patients with lingering pulmonary symptoms. The etiology of symptoms is unknown, but it is probable that the inflammatory processes associated with COVID-19 may inhibit HPV.

This is an open, randomized, controlled clinical trial with hyperbaric oxygen therapy delivered by a hyperbaric chamber as the intervention. Twelve patients will receive ten HBO therapy (HBOT) over a 2-3-week period, and twelve patients will serve as controls and receive no HBOT. Each HBOT session will administer oxygen (O2) at 2.4 atmospheres absolute pressure (ATA) (100% O2) for 90 minutes in a hyperbaric chamber.


Covid19, hyperbaric oxygen, hyperbaric oxygen therapy, long covid, COVID-19, Post-Acute COVID-19 Syndrome


You can join if…

Open to people ages 18-65

  • 18 - 65 years old
  • COVID-19 at least 12 weeks prior, +PCR test and/or documented clinical symptoms
  • Desaturate to <94% during the 6-MWT and/or have abnormal spirometry or DLCO values below the lower limit of normal (LLN)
  • Active life-style before contracting COVID-19

You CAN'T join if...

  • Pregnant or lactating women
  • Individuals that are unable walk or get in and out of bed by themselves
  • Weighing over 300 lbs. or Body mass index (BMI) >30
  • Inability to provide written informed consent
  • Inability or unwillingness to adhere to 10 HBOT treatment sessions over a 2 to 3 week- time period or to complete follow up questionnaires/telephone contacts.
  • Claustrophobia and inability to enter the hyperbaric chamber for session.
  • Inability to effectively equalize the middle ear during ambient pressure changes. History of tympanic membrane perforation, head and neck surgery with compromised Eustachian tube function, including tracheostomy, mastoidectomy, middle ear surgical procedures and cochlear implants.
  • History of pulmonary disease prior to COVID-19 including asthma, chronic obstructive pulmonary disease (COPD), bullous lung disease, previous thoracotomy, pneumothorax or history of pneumothorax prior to having COVID-19.
  • History of cardiovascular disease prior to having COVID-19.
  • History of type 1 or 2 diabetes prior to having COVID-19
  • History of neurovascular diseases (e.g. recent stroke) prior to having COVID-19
  • History of uncontrolled hypertension prior to having COVID-19
  • History of retinitis pigmentosa prior to having COVID-19
  • History of renal disease prior to having COVID-19
  • History of seizure disorder prior to having COVID-19
  • Active or uncontrolled cancer diagnosis.
  • Active or uncontrolled psychiatric disease.
  • Acute upper respiratory tract infection
  • History of exposure to bleomycin
  • Taking the following concomitant medications: PDE5 inhibitors, carbonic anhydrase inhibitors, beta blockers, alpha blockers, nitrates.
  • MRI incompatibilities- a cardiac pacemaker, metal fragments in the eyes, skin, body; heart valve replacement, brain clips, venous umbrella, intercranial bypass, renal, aortic clips, prosthetic devices for middle ear, eye, joint or penile implants, joint replacements; hearing aid, neurostimulator, insulin pump, I.U.D, pregnant or trying to become pregnant, shunts/stents, metal mesh/coil implants; metal plate/pin/screws/wires, any other implants; permanent eyeliner/eyebrows with metal containing dyes, dental work within 6 weeks, claustrophobia.
  • Involved in another clinical trial that does not allow enrollment in other clinical trials.


  • Univeristy of California San Diego
    La Jolla California 92093 United States


currently not accepting new patients, but might later
Start Date
Completion Date
Peter Lindholm
Phase 2 COVID-19 Research Study
Study Type
Expecting 24 study participants
Last Updated