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Study of Hyperbaric Oxygen Therapy Administered Once or Twice Daily for Patients with Acute Acoustic Trauma

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial focuses on treating Acute Acoustic Trauma, a condition where hearing is damaged due to exposure to loud noise. The study investigates the effectiveness of Hyperbaric Oxygen Therapy (HBOT), a treatment where patients breathe pure oxygen in a special pressurized chamber, to help improve hearing after noise-related injury.

The purpose of the study is to compare two different treatment schedules of hyperbaric oxygen therapy. The study will evaluate whether receiving oxygen therapy twice per day for five days works better than having it once daily for ten days in improving hearing levels. The treatment involves breathing oxygen through inhalation in either compressed or cryogenic (extremely cold) form.

Participants will receive treatment for up to 12 months and will have their hearing tested one month after completing the therapy to measure how much their hearing has improved. The oxygen used in the treatment will be administered at concentrations of up to 100% by volume.

The research process

The trial runs in 4 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    Your hearing will be evaluated through audiometry to confirm acute acoustic trauma (sudden hearing loss caused by exposure to loud noise)

    The assessment must take place between 24 and 72 hours after exposure to the loud noise

    To qualify, you need to have hearing loss of at least: 30 dB at one frequency, or 25 dB at two frequencies, or 20 dB at three frequencies

  2. Step 2

    Treatment assignment

    You will be assigned to one of two treatment schedules:

    Schedule A: Hyperbaric Oxygen Therapy (breathing pure oxygen in a pressurized chamber) twice daily for 5 days

    Schedule B: Hyperbaric Oxygen Therapy once daily for 10 days

  3. Step 3

    Treatment period

    You will receive oxygen therapy according to your assigned schedule

    The treatment involves breathing pure oxygen through inhalation in a specialized chamber

    The total treatment duration will be either 5 or 10 days, depending on your assigned group

  4. Step 4

    Follow-up evaluation

    One month after completing treatment, your hearing will be tested again

    The test will measure the improvement in hearing across all affected frequencies

    This evaluation will determine how effective the treatment has been in improving your hearing

Who can join the trial?

8 criteria

  • Patient must be diagnosed with acute acoustic trauma (sudden hearing damage caused by exposure to very loud noise) confirmed by hearing test
  • Patient must visit the ear specialist (otorhinolaryngologist) between 24 and 72 hours (1-3 days) after experiencing the acoustic trauma
  • Patient must be 18 years or older
  • Patient must have hearing loss meeting at least one of these conditions:
    • Loss of 30 decibels (dB) or more at one tested frequency, or
    • Loss of 25 decibels or more at two tested frequencies, or
    • Loss of 20 decibels or more at three tested frequencies
    • Both men and women can participate
    • If previous hearing test results exist, the new hearing loss must meet the minimum levels listed above

Who cannot join the trial?

11 criteria

  • People under 18 years old cannot participate in this study
  • Patients who have any condition that would prevent them from safely undergoing hyperbaric oxygen therapy (treatment in a pressurized chamber with pure oxygen)
  • Those who have experienced hearing loss more than 14 days before seeking treatment
  • Patients with permanent hearing damage from previous conditions
  • People who cannot commit to either once-daily treatment for 10 days or twice-daily treatment for 5 days
  • Those with untreated ear infections or active ear diseases
  • Patients who are claustrophobic (fear of enclosed spaces) as the treatment requires staying in an enclosed chamber
  • People with certain lung conditions that could be affected by pressurized oxygen
  • Those who have recently had ear or head surgery
  • Patients currently participating in other clinical trials
  • People unable to provide informed consent for the treatment
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Verified sites

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  • Verified

    Amsterdam UMC

    The NetherlandsAmsterdam, The Netherlands

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Investigated drugs

Hyperbaric Oxygen Therapy (HBOT) is a medical treatment where a person breathes pure oxygen while inside a pressurized chamber. During this therapy, the patient's body receives much more oxygen than it would by breathing regular air at normal pressure. This treatment is being studied to help patients who have experienced sudden hearing loss due to acoustic trauma. The oxygen-rich environment helps repair damaged tissues and promotes healing in the inner ear. The trial compares two different treatment schedules of the same therapy: - Treatment given twice per day for five days - Treatment given once per day for ten days

What is already known about the treatment

Hyperbaric Oxygen Therapy (HBOT) - A medical treatment that involves breathing pure oxygen in a pressurized chamber, where the air pressure is increased to three times higher than normal atmospheric pressure. This therapy is used in treating acute acoustic trauma by enhancing oxygen delivery to damaged inner ear tissues, potentially reducing inflammation and promoting healing of damaged cells. HBOT works by increasing the amount of oxygen dissolved in the blood plasma, which can penetrate areas with reduced blood flow and help restore normal tissue function. This non-invasive treatment belongs to the class of pressure-based therapies and is administered in specialized chambers under medical supervision, typically in sessions lasting between 60 to 90 minutes.

Investigated diseases

Acute acoustic trauma – A sudden injury to the inner ear caused by exposure to very loud noise or sound blast. The condition occurs when intense sound waves damage the delicate structures in the cochlea, particularly affecting the hair cells responsible for hearing. Acoustic trauma typically results in immediate hearing problems, often accompanied by ringing in the ears (tinnitus). The damage can affect different frequencies of hearing, with some people experiencing partial hearing loss in specific frequency ranges. The condition can develop after exposure to a single extremely loud noise or after brief exposure to intense sounds like explosions or gunfire.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2024-517739-35-00Estimated enrolment84 patientsSponsorAmsterdam UMC

sourced from the EU Clinical Trials Register and site verification

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