Evaluable
Conditions
Keywords
ARDS : Acute Respiratory Distress Syndrome, CACC : Continuous Anterior Chest Compression, VILI : Ventilator-Induced Lung Injury, ARDS,Human: Adult Respiratory Distress Syndrome
Brief summary
The aim is to test the physiological effects of continuous anterior chest compression in patients with severe to moderate ARDS.
Detailed description
Acute respiratory distress syndrome (ARDS) is usually characterized by inhomogeneous lesions, leading to an inhomogeneous distribution of the mechanical ventilation with the following several deleterious effects: atelectrauma of dependent posterior areas and overdistension in the anterior ones. Therefore, the gold standard treatment is to prevent VILI with lung protective ventilation : low tidal volume, high positive end expiratory pressure and prone positioning which is a technique that reduces mortality. Prone positioning has several beneficial effects : it relieves cardiac compression of the supporting lung, it stiffens the anterior chest wall thus limiting the risk of overdistension of anterior areas and promotes recruitment of non-dependent posterior pulmonary units. The overall effect is a more uniform distribution of transpulmonary pressures and improved ventilation to perfusion ratios. Similar to prone positioning, continuous anterior chest wall compression stiffens the anterior chest wall. The investigators hypothesize that such reduction in anterior chest wall compliance may protect against overdistension and promote the redistribution of the ventilation in posterior areas.
Interventions
Patients with severe to moderate ARDS who were placed in prone position by the attending physician : * First CACC : the applied pressure is equal to the one observed in the prone position * Second CACC : The applied pressure is set at 60 - 80 cmH20
Sponsors
Assistance Publique - Hôpitaux de Paris
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
Clinical trials with a single arm
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age ≥ 18 ans * Intubated moderate and severe ARDS according to the Berlin definition (PaO2/FiO2 ratio \<= 200 mmHg) * The patent must be sedated and paralyzed * Informed consent from patient or family members
Exclusion criteria
* Extracorporeal membrane oxygenation (ECMO) * Pneumothorax * Thoracic trauma during the last 3 months * Refractory shock * Contraindication to EIT monitoring (e.g. burns, pacemaker, thoracic wounds limiting electrode belt placement) * Pregnancy * Any contra-indication to esophageal manometry (less than one month esophagus surgery, bronchopleural or esotracheal fistula, latex allergy) * No social care * Adults under Guardianship, curatorship or protection of the court
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The end inspiratory transpulmonary pressure (PL-insp) in centimetre of water | Through study completion (up to 6 hours) | The transpulmonary pressure will be measured by using an esophageal catheter connected to a differential pressure transducer. The PL-insp will be calculated using the ratio between the elastance of the lung (El) and of the respiratory system (Ers) expressed in centimetre of water thanks to this formula PL-insp = Plateau pressure x (El/Ers). The PL-insp between the different protocol conditions will be compared (After 16 hours of prone position, in supine position, 15mn after CACC with a pressure equal to the one observed in the prone position, 15mn after CACC with a pressure set at 60 - 80 cmH20, 15mn after taking off the CACC in supine position ). CACC will be considered protective if there is a decrease in Pl-insp. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Regional pulmonary compliances in centimetre of water | Through study completion (up to 6 hours) | Evaluation and comparison of pulmonary compliances in the different regions of interest (ROI) measured by Electrical Impedance Tomography (EIT) in the different protocol conditions. |
| Lung mechanics : Airways pressure, Flow curves and Esophageal pressure | Through study completion (up to 6 hours) | Airways pressure (Paw) will be measured in cmH2O and recorded by the mean of a differential pressure transducer. Flow curves will be measured in L/mn and recorded by the mean of a pneumotachograph connected to the ventilator circuit. Esophageal pressure (Pes) will be measured in cmH2O and recorded thanks to an esophageal balloon catheter introduced in the mid-esophagus of the patient and connected to differential pressure transducer. Evaluation and comparison of respiratory mechanics in the different protocol conditions. |
| Pulmonary ventilation distribution in percentage | Through study completion (up to 6 hours) | Evaluation and comparison of the distribution of ventilation in the different regions of interest (ROI) measured by Electrical Impedance Tomography (EIT) in the different protocol conditions |
| Recruitment-to-inflation (R/I) ratio | Through study completion (up to 6 hours) | Evaluation and comparaison of R/I in the different protocol conditions |
| Hemodynamics | Through study completion (up to 6 hours) | Heart rate will be expressed in beats per minute, arterial blood pressure will be expressed in millimetre of mercury and norepinephrine perfusion will be expressed in milligrams per hour. |
| Incidence of CACC adverse events | Through study completion (up to 6 hours) | CACC will be interrupted if : * Reduction in oxygen saturation (SpO2) beneath 88% despite FiO2 optimisation. * Reduction in mean arterial pressure beneath 60 mmHg * Increase in norepinephrine perfusion beyond 0.5 mg/h |
| Arterial blood gazes (ABG | Through study completion (up to 6 hours) | pH, PaCO2 and PaO2 will be measured by standard clinical technique using the ICU blood gaz analyzer. PaCO2 and PaO2 will be expressed in millimetre of mercury. |
| End expiratory lung impedance (EELZ) expressed in arbitrary units | Through study completion (up to 6 hours) ] | Evaluation and comparison of EELZ using EIT in the different protocol conditions. |
Countries
France
Contacts
PRINCIPAL_INVESTIGATORGuillaume CARTEAUX, MD, PhD
APHP
Outcome results
None listed