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

Centre Hospitalier Metropole Savoie

Status: Enrolling

Conditions: Lung Diseases, Interstitial; Healthy; Hyperventilation Syndrome; Chronic Heart Failure; Pulmonary Disease, Chronic Obstructive; Pulmonary Arterial Hypertension

Treatments: Other: simultaneous determination of PaCO2 and PtCO2; Other: Hyperventilation test; Other: Exercise test

Study type: Interventional

Funder types: Other

Identifiers

NCT03718780

CHMS18004

Details and patient eligibility

About

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)

Enrollment: 105 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

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)

Trial design

Primary purpose: Other

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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105 participants in 8 patient groups

A1: Patient in intensive care

Experimental group

Description:

Patient in intensive care (n=10): in patients in the intensive care unit of the Centre Hospitalier Metropole Savoie (Chambéry, France), where repeated arterial blood gas analysis is routinely performed (Patients equipped for their usual care with an arterial catheter, enabling repeated arterial blood gas determination ). PaCO2 and Pt CO2 will be measured simultaneously at rest, and during conditions inducing PaCO2 modifications (ventilator settings modifications, or exercise as per routine rehabilitation) Comparison will be done between arterial PaCO2 and PtCO2

Treatment:

Other: simultaneous determination of PaCO2 and PtCO2

A2: Healthy subjects

Experimental group

Description:

Healthy subjects performing a voluntary hyperventilation, in the laboratory room where routine exercise testing is usually done. Comparison will be done between arterialized PaCO2 and PtCO2, at rest, and during an induced voluntary hyperventilation.

Treatment:

Other: Exercise test

Other: Hyperventilation test

B1: Healthy subject

Experimental group

Description:

Subjects, referred for exercise diagnostic testing, and whose results indicate normal cardiac and pulmonary exercise physiology. Measurement, throughout these exercise tests, of the alveolar dead space, and its kinetics, up to peak VO2, then during recovery, in the different conditions listed above. Alveolar dead space will be calculated using the continuous Pt CO2 values observed, and also with some intermittent PaCO2 measurement, done as per routine modus operandi (arterialized earlobe capillary drawn at rest, at ventilatory threshold, and at peak exercise). The values measured through PtCO2 and PaCO2 will be compared at these 3 time points.

Treatment:

Other: Exercise test

B2: Chronic Obstructive Pulmonary Disease

Experimental group

Description:

Measurement, throughout these exercise tests, of the alveolar dead space, and its kinetics, up to peak VO2, then during recovery, in the different conditions listed above. Alveolar dead space will be calculated using the continuous Pt CO2 values observed, and also with some intermittent PaCO2 measurement, done as per routine modus operandi (arterialized earlobe capillary drawn at rest, at ventilatory threshold, and at peak exercise). The values measured through PtCO2 and PaCO2 will be compared at these 3 time points.

Treatment:

Other: Exercise test

B3: Interstitial Lung Disease (ILD)

Experimental group

Description:

Measurement, throughout these exercise tests, of the alveolar dead space, and its kinetics, up to peak VO2, then during recovery, in the different conditions listed above. Alveolar dead space will be calculated using the continuous Pt CO2 values observed, and also with some intermittent PaCO2 measurement, done as per routine modus operandi (arterialized earlobe capillary drawn at rest, at ventilatory threshold, and at peak exercise). The values measured through PtCO2 and PaCO2 will be compared at these 3 time points.

Treatment:

Other: Exercise test

B4: Chronic heart failure (CHF)

Experimental group

Description:

Measurement, throughout these exercise tests, of the alveolar dead space, and its kinetics, up to peak VO2, then during recovery, in the different conditions listed above. Alveolar dead space will be calculated using the continuous Pt CO2 values observed, and also with some intermittent PaCO2 measurement, done as per routine modus operandi (arterialized earlobe capillary drawn at rest, at ventilatory threshold, and at peak exercise). The values measured through PtCO2 and PaCO2 will be compared at these 3 time points.

Treatment:

Other: Exercise test

B5: Pulmonary Arterial Hypertension (PAH)

Experimental group

Description:

Measurement, throughout these exercise tests, of the alveolar dead space, and its kinetics, up to peak VO2, then during recovery, in the different conditions listed above. Alveolar dead space will be calculated using the continuous Pt CO2 values observed, and also with some intermittent PaCO2 measurement, done as per routine modus operandi (arterialized earlobe capillary drawn at rest, at ventilatory threshold, and at peak exercise). The values measured through PtCO2 and PaCO2 will be compared at these 3 time points.

Treatment:

Other: Exercise test

B6: inappropriate hyperventilation syndrome

Experimental group

Description:

Measurement, throughout these exercise tests, of the alveolar dead space, and its kinetics, up to peak VO2, then during recovery, in the different conditions listed above. Alveolar dead space will be calculated using the continuous Pt CO2 values observed, and also with some intermittent PaCO2 measurement, done as per routine modus operandi (arterialized earlobe capillary drawn at rest, at ventilatory threshold, and at peak exercise). The values measured through PtCO2 and PaCO2 will be compared at these 3 time points.

Treatment:

Other: Exercise test