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Status unknownNCT04691440ENDOHOTUpdated Dec 31, 2020

Hyperbaric Oxygen Treatment in Humans With Gram Positive Cocci Endocarditis

A Phase 2 interventional study of Hyperbaric oxygen in Infectious Endocarditis, sponsored by Ole Hyldegaard. Status unknown at 1 site in Denmark. Open to participants aged 18 Years to 95 Years. Per ClinicalTrials.gov, last updated 2020-12-31.

Sponsored by Ole Hyldegaard · Phase 2, Interventional, and Treatment

The sponsor has not verified this record recently (last verified Dec 2020), so the status shown — last known as Recruiting — may be out of date.

From the registry’s dates

  • Registered 1 year after the study started (first participant enrolled Dec 2019, registered Dec 2020).
Phase
Phase 2
Study type
Interventional
Enrollment
10
Allocation
Not applicable
Ages
18 Years to 95 Years
Sex
All
01

Study summary

Infectious endocarditis (IE) is defined as an infection anywhere on the endocardium, most often localised to the cardiac valves. It is an infection with an increasing incidence and in Denmark with 6-700 new cases annually. Approximately 45% of the patients must undergo cardiac surgery with replacement of infected cardiac valves by prosthetic valves.

Recently, the formation of biofilms infections has drawn attention with respect to the effects of hyperbaric re-oxygenation of stricken tissues as anaerobic bacterial metabolism with low levels of activity within the biofilm environment, may be responsible for the development of antimicrobial resistance. Polymorphonuclear leukocytes (PMNs) consume available oxygen in the conversion of oxygen to ROS and in the formation of reactive nitrogen species (RNS) by inducible nitric oxide (iNOS) as PMN's are activated by bacteria.

In pre-clinical context the effect of hyperbaric oxygen treatment (HBOT) in re-oxygenating biofilm related infections have been demonstrated in infected lungs with Pseudomonas aeruginosa and staphylococcus aureus endocarditis.

Adjunctive HBOT has never been offered to patients with IE. However, HBOT may be associated with reduced compliance and side effects, such as equalisation problems of ears and sinuses and confinement anxiety, and the treatment is organizational challenging. On this basis the investigators suggest an initial feasibility study as the basis for a later and larger scaled randomized controlled trial of HBOT in patients with IE.

Read the detailed description

During antibiotic treatments with the indicated antibiotics the susceptible bacteria are subjected to metabolic changes of the Krebs cycles leading to intrabacterial accumulation of toxic hydroxyl oxygen radicals. The intrabacterial toxic reactive oxygen species (ROS) can subsequently react with DNA, lipids or proteins resulting in damages of those bacterial components adding to the killing of the bacteria. A consequence is that bactericidal antibiotics have reduced activity in infectious foci with poor oxygen supply like in abscesses or in biofilm infections as in IE and/or rapid consumption of oxygen due to PMN influx. The bacterial damages may, if killing is not obtained, result in mutations and selection of antibiotic resistant mutants.

However, these discoveries also provide a possibility for improving the antibacterial effect by increasing the oxygen pressure in the infectious focus. This can be obtained by increasing oxygen tension in the tissues by treating the patients with HBOT - and have been shown in vitro and in vivo pre-clinical experiments. Exposing Pseudomonas aeruginosa biofilm models in vitro to HBOT has proved effective by significantly increasing the bactericidal effect of ciprofloxacin.

More important, in an animal (rats) model of left-sided S. aureus IE on the aortic valves, tobramycin killing effect was significantly improved by adding HBOT as adjunctive therapy. Moreover, the rats revealed a reduced inflammatory response and improved clinical scores. No side effects were recorded during that study.

In addition, the HBOT is also believed to improve the antibacterial effect of the PMNs, and thereby add to an enhanced elimination of infectious focus. This is being estimated by measurements of the respiratory burst of the PMNs, as well as their phagocytic capacity right before and right after the HBOT.

02

Conditions studied

  • Infectious Endocarditis
03

In context

Lead sponsor

Ole Hyldegaard is the lead sponsor of 6 studies on the registry; 1 is open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 95 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Left sided IE with gram positive cocci.
  2. IE has been diagnosed according to modified Duke Criteria.
  3. Patients must be stable, by means of no need for hemodynamic pressure support.
  4. The patient must be able to be seated for the 1.5 hour the HBOT at least two times a day for 3 days.
  5. The patient must be able to perform Valsalva's - or Frenzels manoeuvre - to equalize middle ear pressure. As prophylaxis, all patients will receive detumescent nose drops as Otrivin® to facilitate ear- and sinuses equilibration. In the rare event it is still not possible for the patient to equalize pressure, a paracentesis or drainage of the tympanic membrane must be performed by the ear-nose and throat (ENT) doctor. All according to daily practice.
  6. The upstart of HBOT must be within the first 2 weeks of relevant antibiotic IE therapy.
  7. If a central venous catheter has been inserted, a chest X-ray must confirm no suspicion of pneumothorax.
  8. Patients must be >18-years old.

Exclusion criteria

Exclusion Criteria:

  1. Claustrophobia that cannot be reversed by mild sedatives.
  2. Patients requiring mechanical ventilation.
  3. Undrained pneumothorax
  4. Pregnancy
  5. Unable to follow and understand simple commands
  6. Non-compliant
05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
10 participants (estimated)

Study arms

  • Experimental
    HBOT

    Hyperbaric oxygen breathing at 2.4 atm.abs for 90 minutes. The course of hyperbaric oxygen treatment comprises a total of 6 pressure exposures, distributed 2 times daily, for 3 days.

    Drug: Hyperbaric oxygen

Interventions

  • The course of hyperbaric oxygen treatment comprises a total of 6 pressure exposures, distributed 2 times daily, for 3 days.

06

What researchers measure

Primary outcomes

  1. Changes in baseline characteristics with definite IE.

    Standard clinical assesments of IE and paraclinical data

    Time frame: Up to 12 weeks

07

Study locations

1 of 1 sites recruiting
  • Rigshospitalet
    Copenhagen, 2100, Denmark
    Recruiting
    • Mia Pries-Heje, MD · Contact
08

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Started Dec 2019 (actual). Primary completion is estimated for Jul 2021, 19 months after the start.

How these figures are worked out, and which studies are left out of them.

Registered
Dec 18, 2020
First posted
Dec 31, 2020
StartActual
Dec 1, 2019
Primary completionEst.
Jul 1, 2021
CompletionEst.
Dec 31, 2021
Last update
Dec 31, 2020
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Dec 31, 2020, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT04691440
Lead sponsor
Ole Hyldegaard
Responsible party
Ole Hyldegaard (Chief Consultant, MD, Ph.D., Department of HBO, Rigshospitalet, Rigshospitalet, Denmark) — Sponsor-investigator
First posted
Dec 31, 2020
Start date
Dec 1, 2019
Primary completion
Jul 1, 2021 (estimated)
Completion
Dec 31, 2021 (estimated)
Last update
Dec 31, 2020

Study contacts

Ole Hyldegaard, MD, PHD
Contact
ole.hyldegaard@regionh.dk
+4535454092
Ole Hyldegaard, MD, PHD
principal investigator · Rigshospitalet, Denmark

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is status unknown, as verified in Dec 2020. You cannot join it, but the record below documents what was studied.

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Studies of the drug tested here: Hyperbaric Oxygen

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