Impact of Hyperoxia and Involvement of the Immune System in Diving Accident (OXYDIVE)

The impact of oxygen therapy in many pathologies has been subject of recent work, arguing both favourable and harmful effects. Consequently, one can wonder about the influence of hyperoxic gas mixture during diving on the genesis of decompression sickness, but also about the systematic application of normobaric and hyperbaric oxygen in case of proven decompression sickness.

In mammals, normoxic concentrations have been redefined at 20-100 mbars at the extracellular level and below 10 mbars in the mitochondria.

Under hyperbaric conditions, most of the oxygen being dissolved in blood plasma, a state of hyperoxia is established which escapes the usual delivery and regulation system represented by red blood cells.

The results of our team's previous work suggest a specific effect of diving on the levels of circulating mitochondrial DNA (mtDNA), suggesting cellular destruction linked to hyperoxia/hyperbaria. In fact, our studies, carried out on both animals and human divers, have shown that diving accident leads to an increase in mtDNA levels and an immune reaction through the mobilisation of leukocytes.

The main objective of this study is to compare the influence of oxygen partial pressure levels on the evolution of clinical and biological variables during hyperbaric oxygen therapy sessions in healthy versus injured divers.

Study Overview

• Status: Recruiting
• Conditions: Decompression Sickness
• Intervention / Treatment: Procedure: Hyperbaric oxygen therapy; Procedure: Diving simulation

• Study Type: Interventional
• Enrollment (Anticipated): 265
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Nicolas VALLEE, PhD; Phone Number: +33 483162849; Email: nicolas.vallee@intradef.gouv.fr
• Study Contact Backup: Name: Céline RAMDANI, MD, PhD; Phone Number: +33 483162844; Email: celine.ramdani@intradef.gouv.fr

Study Locations

• France
  • Toulon, France, 83800
    • Recruiting
    • Hôpital d'Instruction des Armées Sainte-Anne
    • Contact: Nicolas VALLEE, PhD; Phone Number: +33 483162849; Email: nicolas.vallee@intradef.gouv.fr
    • Contact: Céline RAMDANI, MD, PhD; Phone Number: +33 483162844; Email: celine.ramdani@intradef.gouv.fr
    • Principal Investigator: Céline RAMDANI, MD, PhD
    • Principal Investigator: Sarah RIVES, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Healthy subject with no contraindications to diving OR patient admitted to the hospital for suspicion of a diving accident OR patient admitted to the hospital for hyperbaric oxygen therapy

Exclusion Criteria:

• Contraindication to diving or contraindication to hyperbaric oxygen therapy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Healthy individuals	Procedure: Hyperbaric oxygen therapy; Hyperbaric oxygen therapy protocol; Procedure: Diving simulation; Hyperbaric chamber diving simulation protocol
Experimental: Decompression sickness patients	Procedure: Hyperbaric oxygen therapy; Hyperbaric oxygen therapy protocol

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evolution of decompression sickness clinical symptoms	Decompression sickness clinical symptoms will be assessed through a medical examination after each hyperbaric session. Decompression sickness clinical symptoms include: paresthesia, sensory deficit, motor deficit, spinal pain, sphincter disorder and brain injury. The evolution of symptoms will be rated as following: total regression, improvement, stabilization, fluctuation or worsening	Until the end of the oxygen therapy treatment (up to 1 year)

Collaborators and Investigators

• Sponsor: Direction Centrale du Service de Santé des Armées

Study record dates

Study Major Dates

• Study Start (Actual): March 30, 2022
• Primary Completion (Anticipated): March 30, 2028
• Study Completion (Anticipated): March 30, 2028

Study Registration Dates

• First Submitted: December 13, 2020
• First Submitted That Met QC Criteria: March 8, 2021
• First Posted (Actual): March 10, 2021

Study Record Updates

• Last Update Posted (Actual): April 28, 2023
• Last Update Submitted That Met QC Criteria: April 27, 2023
• Last Verified: April 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Wounds and Injuries; Signs and Symptoms, Respiratory; Barotrauma; Hyperoxia; Decompression Sickness
• Other Study ID Numbers: 2019PBMD05

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No