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

Study Status: Recruiting
Recruit Status: Recruiting
Study Type: Interventional

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

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 Summary:

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.


Sponsor: University Hospital, Brest

Current Primary Outcome: Venous bubbles will be detected by precordial Doppler [ Time Frame: 30 minutes after the dive ]

Venous bubbles will be detected by precordial Doppler


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Vascular abnormality [ Time Frame: 60 minutes after the dive ]
    Assessement of microvascular reactivity by brachial artery flow mediated dilation
  • Coagulation activation [ Time Frame: 60 minutes after the dive ]
    Assessment of blood coagulation factor after the dive
  • Inflammatory activation [ Time Frame: 60 minutes after the dive ]
    Assessment of inflammatory factor after the dive


Original Secondary Outcome: Same as current

Information By: University Hospital, Brest

Dates:
Date Received: March 16, 2016
Date Started: March 2016
Date Completion: April 2018
Last Updated: January 13, 2017
Last Verified: January 2017