Early Pulmonary Effects of Excursion Deep Diving With Closed-circuit Gas Recycling: SPIDD Study

Study Overview
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Brief Summary
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Scuba diving with closed circuit gas rebreathers is currently booming. Initially developed for professional and military diving, this type of diving has become very successful in recreational activities. The possibilities offered by this equipment are immense and reduce the constraints of exploration time and depth. More and more divers are seeking to reach depths previously considered unusual or inaccessible in recreational diving, beyond 100 meters. By pushing back these limits, the diver is exposed to new risks which should lead to a reflection on the means of prevention and treatment in case of incident. The physiological repercussions of these deep dives are not well known. During daily deep excursions in the 90-120 meter zone, there is a significant reduction in vital capacity on leaving the dive, which persists and worsens the following day. It seems necessary to confirm the importance of this impairment, never documented before, and to explore its mechanisms. A better knowledge of this respiratory impact could allow to improve the prevention and the preliminary evaluation of the medical aptitude of these divers.

Official Title
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Early Pulmonary Effects of Excursion Deep Diving With Closed-circuit Gas Recycling: SPIDD Study

Conditions
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Physiopathology

Intervention / Treatment
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* Diagnostic Test: Pre and post dive examinations


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diver ≥ 18 years old Recreational rebreather diver with a recognised qualification (Mixed Gas CCR training or equivalent) and the necessary experience for this type of diving who has scheduled a dive in the 60 metre depth zone Diver using his/her own equipment, i.e. a closed circuit rebreather with back lungs meeting CE standards. Having a medical certificate of no contraindication to the practice of underwater activities < 1 year issued by an authorised doctor Having taken out personal insurance covering this type of activity Voluntary and having given his/her express, free and informed consent Affiliated to the Social Security Exclusion Criteria: Diver refusal Known previous respiratory pathology Use of medication that may alter pulmonary and/or vascular function as well as inflammatory and haemostasis parameters Any temporary contraindication to the practice of scuba diving Patient under guardianship or trusteeship Immersion beyond 30 metres within 7 days or any scuba diving within the previous 48 hours.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Diving arm<br>The standard arm involves all participants in the study. Subjects will perform pre-dive and post-dive examinations to characterize the respiratory impact of deep water diving | Diagnostic Test: Pre and post dive examinations<br>* Performing pre-dive examinations: - EFR by plethysmography cabin Realization of the examinations the day of the dive: Portable Spirometry Pulmonary ultrasound Cardiac ultrasound Measurement of circulating bubbles ECG Venous blood sampling (biological collection) Water balance (Δweight/water intake) EFR by plethysmography cabin Weight measurement Realization of the examinations the day after the dive: Venous blood sample (biological collection) Portable Spirometry Pulmonary ultrasound Cardiac ultrasound Weight measurement<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Variation in Vital Capacity Measurement before and after diving | Vital capacity measurement will be performed by plethysmography and spirometry (Measurement of mobilizable and non-mobilizable lung volumes (mL)) | Day 0 (before diving) | 
| Variation in Vital Capacity Measurement before and after diving | Vital capacity measurement will be performed by plethysmography and spirometry (Measurement of mobilizable and non-mobilizable lung volumes (mL)) | Day 0 (after diving) | 
| Variation in Vital Capacity Measurement before and after diving | Vital capacity measurement will be performed by plethysmography and spirometry (Measurement of mobilizable and non-mobilizable lung volumes (mL)) | Day +1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Variations in Spirometry data before and after diving | Measurement of SPO2 (%), CVF (L), VEMS (L), VEMS/CVF (%), DEP (L/S) and DEMM (L/S) before and after diving by spirometry | Day -XX before diving | 
| Variations in Spirometry data before and after diving | Measurement of SPO2 (%), CVF (L), VEMS (L), VEMS/CVF (%), DEP (L/S) and DEMM (L/S) before and after diving by spirometry | Day 0 (before diving) | 
| Variations in Spirometry data before and after diving | Measurement of SPO2 (%), CVF (L), VEMS (L), VEMS/CVF (%), DEP (L/S) and DEMM (L/S) before and after diving by spirometry | Day 0 (after diving) | 
| Variations in Spirometry data before and after diving | Measurement of SPO2 (%), CVF (L), VEMS (L), VEMS/CVF (%), DEP (L/S) and DEMM (L/S) before and after diving by spirometry | Day +1 | 
| Variations in plethysmography data before and after diving | Measurement of CV max (L), CVF (L), VRE (L), VRI (L), VT (L), VEMS (L), VR (L) and CPT (L) before and after diving by plethysmography | Day -XX before Day 0 | 
| Variations in plethysmography data before and after diving | Measurement of DEP (L.S), DEM 75 (L/S), DEM 50 (L/s), DEM 25 (L/S) before and after diving by plethysmography | Day -XX before Day 0 | 
| Variations in plethysmography data before and after diving | Measurement of CV max (L), CVF (L), VRE (L), VRI (L), VT (L), VEMS (L), VR (L) and CPT (L) before and after diving by plethysmography | Day 0 (before diving) | 
| Variations in plethysmography data before and after diving | Measurement of DEP (L.S), DEM 75 (L/S), DEM 50 (L/s), DEM 25 (L/S) before and after diving by plethysmography | Day 0 (before diving) | 
| Variations in plethysmography data before and after diving | Measurement of CV max (L), CVF (L), VRE (L), VRI (L), VT (L), VEMS (L), VR (L) and CPT (L) before and after diving by plethysmography | Day 0 (after diving) | 
| Variations in plethysmography data before and after diving | Measurement of DEP (L.S), DEM 75 (L/S), DEM 50 (L/s), DEM 25 (L/S) before and after diving by plethysmography | Day 0 (after diving) | 
| Variations in plethysmography data before and after diving | Measurement of CV max (L), CVF (L), VRE (L), VRI (L), VT (L), VEMS (L), VR (L) and CPT (L) before and after diving by plethysmography | Day +1 | 
| Variations in plethysmography data before and after diving | Measurement of DEP (L.S), DEM 75 (L/S), DEM 50 (L/s), DEM 25 (L/S) before and after diving by plethysmography | Day +1 | 
| Variations in DLCO before and after diving | Measurement DLCO (mmol/(min*kPa) before and after diving | Day 0 (before diving) | 
| Variations in DLCO before and after diving | Measurement DLCO (mmol/(min*kPa) before and after diving | Day 0 (after diving) | 
| Variations in DLCO before and after diving | Measurement DLCO (mmol/(min*kPa) before and after diving | Day +1 | 
| Variations in lung ultrasound (B lines) before and after diving | A B-line count should be performed, which is defined as vertical artefacts, mobile with breathing, continuous, originating from the pleural line and erasing the other artefacts. These artefacts indicate interstitial damage, the importance of which correlates with their number and a very good correlation with the quantity of extrapulmonary water. | Day 0 (before diving) | 
| Variations in lung ultrasound (B lines) before and after diving | A B-line count should be performed, which is defined as vertical artefacts, mobile with breathing, continuous, originating from the pleural line and erasing the other artefacts. These artefacts indicate interstitial damage, the importance of which correlates with their number and a very good correlation with the quantity of extrapulmonary water. | Day 0 (after diving) | 
| Variations in lung ultrasound (B lines) before and after diving | A B-line count should be performed, which is defined as vertical artefacts, mobile with breathing, continuous, originating from the pleural line and erasing the other artefacts. These artefacts indicate interstitial damage, the importance of which correlates with their number and a very good correlation with the quantity of extrapulmonary water. | Day +1 | 
| Variations in lung ultrasound (condensations) before and after diving | Ultrasound signs of condensation or pleural effusions should be observed before and after diving. | Day 0 (before diving) | 
| Variations in lung ultrasound (condensations) before and after diving | Ultrasound signs of condensation or pleural effusions should be observed before and after diving. | Day 0 (after diving) | 
| Variations in lung ultrasound (condensations) data before and after diving | Ultrasound signs of condensation or pleural effusions should be observed before and after diving. | Day +1 | 
| Variations in cardiac ultrasound pulmonary pressure (PAPs) before and after diving | Pulmonary arterial pressures are assessed by studying pulmonary artery Doppler flow (Acceleration Time) and right ventricular ejection time (RVET) and calculating the Acceleration/RVET ratio. | Day 0 (before diving) | 
| Variations in cardiac ultrasound pulmonary pressure (PAPs) before and after diving | Pulmonary arterial pressures are assessed by studying pulmonary artery Doppler flow (Acceleration Time) and right ventricular ejection time (RVET) and calculating the Acceleration/RVET ratio. | Day 0 (after diving) | 
| Variations in cardiac ultrasound pulmonary pressure (PAPs) before and after diving | Pulmonary arterial pressures are assessed by studying pulmonary artery Doppler flow (Acceleration Time) and right ventricular ejection time (RVET) and calculating the Acceleration/RVET ratio. | Day +1 | 
| Variations in right ventricle function data before and after diving | Right ventricular systolic function is assessed by measuring the tricuspid annulus plane systolic excursion (TAPSE) in TM mode and calculating the LV shortening fraction. | Day 0 (before diving) | 
| Variations in right ventricle function data before and after diving | Right ventricular systolic function is assessed by measuring the tricuspid annulus plane systolic excursion (TAPSE) in TM mode and calculating the LV shortening fraction. | Day 0 (after diving) | 
| Variations in right ventricle function data before and after diving | Right ventricular systolic function is assessed by measuring the tricuspid annulus plane systolic excursion (TAPSE) in TM mode and calculating the LV shortening fraction. | Day +1 | 
| Variations in decompression (circulating bubbles) data before and after diving | Detection of circulating bubbles by trans-thoracic ultrasound | Day 0 (before diving) | 
| Variations in decompression (circulating bubbles) data before and after diving | Detection of circulating bubbles by trans-thoracic ultrasound | Day 0 (after diving) | 
| Variations in biological markers of coagulation activation before and after diving | Measurement from the serum library (venous blood samples) of coagulation factors (TFPI, procoagulant microparticles, Fibrin monomer, PF4, C3a, C5a and platelet count) before and after diving. The analyses remain to be specified according to the results of other ongoing investigations | Day 0 (before diving) | 
| Variations in biological markers of coagulation activation before and after diving | Measurement from the serum library (venous blood samples) of coagulation factors (TFPI, procoagulant microparticles, Fibrin monomer, PF4, C3a, C5a and platelet count) before and after diving. The analyses remain to be specified according to the results of other ongoing investigations | Day 0 (after diving) | 
| Variations in biological markers of coagulation activation before and after diving | Measurement from the serum library (venous blood samples) of coagulation factors (TFPI, procoagulant microparticles, Fibrin monomer, PF4, C3a, C5a and platelet count) before and after diving. The analyses remain to be specified according to the results of other ongoing investigations | Day +1 | 
| Variations in biomarkers of lipid peroxidation before and after diving | Measurement from the serum library (venous blood samples) of lipoperoxidation (F2-Isoprostane) before and after the dive. The analyses remain to be specified according to the results of other ongoing investigations. | Day 0 (before diving) | 
| Variations in biomarkers of lipid peroxidation before and after diving | Measurement from the serum library (venous blood samples) lipoperoxidation (F2-Isoprostane) before and after the dive. The analyses remain to be specified according to the results of other ongoing investigations. | Day 0 (after diving) | 
| Variations in biomarkers of lipid peroxidation before and after diving | Measurement from the serum library (venous blood samples) lipoperoxidation (F2-Isoprostane) before and after the dive. The analyses remain to be specified according to the results of other ongoing investigations. | Day +1 | 
| Variations in biomarkers of oxidative stress before and after diving | Measurement from the serum library (venous blood samples) of oxidative stress factors before and after the dive. The analyses remain to be specified according to the results of other ongoing investigations. | Day 0 (before diving) | 
| Variations in biomarkers of oxidative stress before and after diving | Measurement from the serum library (venous blood samples) of oxidative stress factors before and after the dive. The analyses remain to be specified according to the results of other ongoing investigations. | Day 0 (after diving) | 
| Variations in biomarkers of oxidative stress before and after diving | Measurement from the serum library (venous blood samples) of oxidative stress factors (as F2-Isoprostane, 8-isoprostane) before and after the dive. The analyses remain to be specified according to the results of other ongoing investigations. | Day +1 | 
| Variations in biological markers of inflammation before and after diving | Measurement of inflammation factors (CRP and IL1-β) from the serum library (venous blood samples) before and after the dive. The analyses remain to be specified according to the results of other ongoing investigations. | Day 0 (before diving) | 
| Variations in biological markers of inflammation before and after diving | Measurement of inflammation factors (CRP and IL1-β) from the serum library (venous blood samples) before and after the dive. The analyses remain to be specified according to the results of other ongoing investigations. | Day 0 (after diving) | 
| Variations in biological markers of inflammation before and after diving | Measurement of inflammation factors (CRP and IL1-β) from the serum library (venous blood samples) before and after the dive. The analyses remain to be specified according to the results of other ongoing investigations. | Day +1 | 
| Variations in water balance before and after diving | Pre- and post-dive water intakes are quantified but no intake restrictions are requested : Weight measured by electronic scale (in kg) | Day 0 (before diving) | 
| Variations in water balance before and after diving | Pre- and post-dive water intakes are quantified but no intake restrictions are requested : Weight measured by electronic scale (in kg) | Day 0 (after diving) | 
| Variations in water balance before and after diving | Pre- and post-dive water intakes are quantified but no intake restrictions are requested : Weight measured by electronic scale (in kg) | Day +1 |