Decreases in Diffusing Lung Capacity for Carbon Monoxide (DLCO) in Occupational Divers and Their Impact on Decompression Sickness Risks

Not Applicable

Completed

• Conditions: Decompression Sickness
• Interventions: Other: 20 meters air dive

• Registration Number: NCT02736006
• Lead Sponsor: University Hospital, Brest

Brief Summary

Diving disorders and particularly Decompression sickness (DCS) represent a major concern in recreational and occupational pressure-related activities. As a result of decompression from higher to lower ambient pressure bubbles which are formed in vascular flow and in tissues take part in embolism then resulting in DCS. Individual factors such as vascular or respiratory defects are now considered to increase the risk of this dysbarism disease.

Detailed Description

2 groups of occupational divers will be separated after a fitness medical examination by regarding DLCO decrease or not.

The divers will be evaluated before and 30, 60, 180 minutes after a 20 meters air dive. Venous bubbles will be detected by precordial Doppler 30 minutes after the dive.

In association with this Doppler, Flow Mediated Dilation, blood samples analysing inflammatory and thrombotic factors and other biomarkers will be explored before and after the dive in order to know how vascular and respiratory tracts in this environment react.

Study Timeline

• Study First Submitted: 2016-03-16
• Study Start: 2016-03-22
• Study First Submitted QC: 2016-04-12
• Study First Posted: 2016-04-13
• Primary Completion: 2017-05-30
• Study Completion: 2017-05-30
• Status Verified: 2017-06
• Last Update Submitted: 2017-06-12
• Last Update Posted: 2017-06-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 16

Inclusion Criteria

• Be professional and voluntary diver
• Man or woman aged 18 years or older
• Diffusing Lung Capacity for Carbon Monoxide measured beforehand in the study
• No medical contraindication for hyperbaric
• No hyperbaric constraint in 3 days before the dive
• No prior Decompression sickness
• Not to follow medicinal treatment modifying the vascular endothelial and/or the coagulation and/or the respiratory function
• Patient affiliated to social security
• Informed and signed

Exclusion Criteria

• Concomitant pathology identified by the Investigator, justifying a contraindication for hyperbaric
• Pregnant and nursing mothers
• Patient who refuse to sign consent form

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
20 meters air dive	20 meters air dive	-

Primary Outcome Measures

Name	Time	Method
Venous bubbles will be detected by precordial Doppler	30 minutes after the dive	Venous bubbles will be detected by precordial Doppler

Secondary Outcome Measures

Name	Time	Method
Coagulation activation	60 minutes after the dive	Assessment of blood coagulation factor after the dive
Inflammatory activation	60 minutes after the dive	Assessment of inflammatory factor after the dive
Vascular abnormality	60 minutes after the dive	Assessement of microvascular reactivity by brachial artery flow mediated dilation

Trial Locations

Locations (1)

Brest, University Hospital; 🇫🇷 Brest, France