CompletedNot Applicable

Assessment of Continuous Measurement of Transcutaneous CO2 for Evaluation of Alveolar Dead Space During Exercise

France140 participantsStarted 2019-02-22

Plain-language summary

The study aim is to monitor, during exercise tests carried out in various conditions, the alveolar dead space, by means of continuous transcutaneous measurement of Pt CO2, which would be used as a surrogate for arterial PaCO2. Validity of this measurement needs to be assessed against arterial sampling (either arterial, or arterialized capillary), especially with regards to the lag time required by the CO2 diffusion from the arterial compartment (PaCO2) to the cutaneous one (PtCO2), in particular when rapid changes of CO2 might be induced by exercise. The evaluation will be done in 2 different settings: * intensive care patients, equipped, for their routine clinical care, with an arterial line; this allows for a precise timed comparison between PaCO2 and PtCO2 readouts; * routine exercise test, where blood gas evaluation is done essentially by means of arterialized earlobe capillary sampling. Following assessment of validity of the measurement (and the lag time PaCO2-PtCO2 which might be necessary to introduce as a correction), evolution of dead space during excise test will be tested in different conditions: Healthy subjects, patients with Chronic Obstructive Pulmonary Disease (COPD), chronic heart failure (CHF), hyperventilation, Pulmonary artery hypertension (PAH), or interstitial lung disease (ILD)

Who can participate

Age range

18 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Written and informed consent, and assent where required. * Either: Patients in intensive care, conscious and in stable hemodynamic condition, who are already equipped with an arterial line for blood gas analysis (as required by the routine practice in intensive care; no arterial line shall be inserted for the purpose of this study) (Part A1) Or patients/subjects scheduled for routine cardio-pulmonary exercise testing. Among these, the following patients will be included: COPD, PAH, healthy subjects, hyperventilation, chronic cardiac failure, interstitial lung diseases (ILD) (Part A2 and Part B) Exclusion Criteria: * Non-French speaking patients/subjects * Unstable hemodynamics * Local cutaneous lesion or infection * Arterial disease such as fistula * Women with the following condition: pregnancy, breast feeding * Persons deprived of liberty (according to article L1121-5 to L1121-8 of the French Public Health Code)

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1This trial tracked CO2 levels through a skin sensor alongside an arterial blood draw during exercise — how invasive is the arterial sampling part, and would my current health allow me to safely do an exercise test like this?
2The study enrolled people with very different conditions, from COPD and pulmonary arterial hypertension to heart failure and even healthy volunteers — given my specific diagnosis, what would my results actually tell us about how well my lungs are exchanging air during exertion?
3Since this trial is already completed, would my doctor be able to share or access any of its findings to help interpret my own exercise test results, particularly around alveolar dead space measurements?
4The trial measured something called VD/VT, which reflects how much of each breath isn't doing useful gas exchange — is that measurement something my care team already tracks, and would knowing it change how my condition is managed?
5Because this is a completed observational-style measurement study rather than a treatment trial, does it offer any direct benefit to me, or is it more about contributing data that might help future patients like me?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Change from baseline of Pt CO2 (transcutaneous CO2 partial pressure) measurement together with PaCO2 (arterial partial CO2 pressure)

Timeframe: at rest and during exercise/hyperventilation: 30 secondes, 1 minute, 1 ½ minute 2, 2 ½ , 3 , 4, 5 and 10 minutes.

Change from baseline by means of continuous measurement of alveolar dead space (VD/VT=(PaCO2-PECO2) /PaCO2), expressed as a percentage from 0% to 100 %) , during exercise test, in different clinical settings

Timeframe: continuous measurement: from rest throughout exercise test ( beginning of test, to maximum load (5-10 minutes), then throughout 5 minutes recovery.

Trial details

NCT IDNCT03718780

SponsorCentre Hospitalier Metropole Savoie

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2023-12-31

View on ClinicalTrials.gov More Pulmonary Disease, Chronic Obstructive trials