Diffuse Acute Respiratory Distress Syndrome (ARDS), Recruitment Maneuver, and sRAGE (DAMAGE Study)

Study Overview
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Brief Summary
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RAGE, the receptor for advanced glycation end products, is a novel marker of alveolar epithelial type I cell injury, and soluble RAGE (sRAGE) is elevated in the plasma and in the pulmonary edema fluid from patients with ALI/ARDS. Few data are available about the influence of ventilatory interventions on levels of sRAGE in the setting of ALI/ARDS. The purpose of this prospective monocentric randomized controlled cross-over study is to describe the effects of a recruitment maneuver (RM) on plasma sRAGE levels during diffuse ARDS.

Detailed Description
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BACKGROUND: The receptor for advanced glycation end products (RAGE) is now identified as a marker of alveolar type I cell injury. RAGE is a member of the immunoglobulin superfamily that acts as a multiligand receptor and is involved in propagating inflammatory responses. While the precise function of RAGE remains unclear, the elevated levels of RAGE, and its soluble isoform sRAGE, correlate with severity of ALI/ARDS in human and animal studies, and higher sRAGE levels could reflect impaired alveolar fluid clearance. Lung morphology, as assessed by loss of aeration distribution patterns on computed tomography (CT) scan, predicts the response to recruitment maneuvers in patients with ARDS: patients presenting with nonfocal (diffuse) lung morphology are more likely to respond to a RM, resulting in an increase in arterial oxygenation, net alveolar fluid clearance, and significant alveolar recruitment as revealed by pressure-volume curve analysis. DESIGN NARRATIVE: The purpose of this prospective, randomized and controlled, cross-over study is to compare the effects of a RM on plasma sRAGE levels (measured 5 minutes before, 5 minutes, 30 minutes, 1 hour, 4 hours and 6 hours after the RM) and plasma sRAGE levels measured during a sham or control sequence, in patients with diffuse ARDS. Mechanically ventilated ICU patients with ARDS criteria (based on the 1994 American-European Consensus Conference definition for ARDS) and nonfocal CT scan lung morphology will be included within 24 hours of disease onset. Then, patients will be randomized into 2 groups: a RM-SHAM group when RM sequence precedes a sham evaluation period, and a SHAM-RM group, in which patients receive a sham sequence before the RM sequence. Patients will receive protective ventilation, as recommended, before, during and after evaluation periods. RM consists of the application of 40 cmH20 airway pressure for 40 seconds. Blood will be sampled from an indwelling arterial catheter, in order to analyze arterial blood gases and sRAGE levels, 5 minutes before the RM (or a 40 second-long sham period), 5 minutes, 30 minutes, 1 hour, 4 hours and 6 hours after the RM (or a 40 second-long sham period). Electric impedance tomography will be evaluated 5 minutes before and 1 hour after the RM.

Official Title
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Effects Of A Recruitment Maneuver On Plasma Levels of sRAGE, The Soluble Form of The Receptor For Advanced Glycation End Products, In Patients With Diffuse Acute Respiratory Distress Syndrome (ARDS)

Conditions
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Acute Respiratory Distress Syndrome

Intervention / Treatment
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* Other: Recruitment Maneuver (RM) sham group
* Other: Sham recruitment maneuver (RM) group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ICU patients under mechanical ventilation Patients within the first 24 hours after onset of ARDS according to the 1994 American-European Consensus Conference (AECC) PaO2/FiO2 ratio < 200 with external PEEP >5 cmH2O Nonfocal loss of aeration based on CT scan lung morphology analysis, as defined by the CT scan ARDS study group criteria Exclusion Criteria: Pregnancy Acute exacerbation of diabetes Dialysis for end-stage kidney disease Alzheimer's disease Amyloidosis Evolutive neoplastic lesion Known or suspected history of allergy to cisatracurium Chronic respiratory disease requiring long term oxygen therapy or long term ventilation Confirmed or suspected elevated intracranial pressure Confirmed or suspected bronchopleural fistula, pneumothorax Persistent hemodynamic instability despite appropriate resuscitation

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Recruitment maneuver (RM) sham group<br>when recruitment maneuver sequence precedes a sham evaluation period | Other: Recruitment Maneuver (RM) sham group<br>* It 's when RM sequence precedes a shame evaluation period<br>|
| Sham Comparator: Sham Recruitment (RM) maneuver group<br>a group in which patients receive a sham sequence before the RM sequence | Other: Sham recruitment maneuver (RM) group<br>* Group in which patients receive a sham sequence before the RM sequence<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma sRAGE |  | 1 hour after the RM | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plasma sRAGE in responders and non-responders to RM |  | 5 minutes before, then 5 minutes, 30 minutes, 4 hours and 6 hours after RM | 
| Kinetics of sRAGE after RM |  | 5 minutes before, and 5 minutes, 30 minutes, 1 hour, 4 hours and 6 hours after RM and after a sham period | 
| Predictive value of baseline sRAGE on the response to RM |  | 5 minutes before, and 5 minutes, 30 minutes, 1 hour, 4 hours and 6 hours after RM | 
| Correlation of plasma sRAGE and response to RM with lung aeration |  | 5 minutes before, and 5 minutes, 30 minutes, 1 hour, 4 hours and 6 hours after RM or sham period | 
| Risk of RM-related pulmonary bacterial translocation |  | 5 minutes before and 30 minutes after RM | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Receptor for advanced glycation end products (RAGE), Soluble RAGE (sRAGE), Recruitment Maneuver, Acute respiratory distress syndrome (ARDS), Alveolar epithelium, Electrical Impedance Tomography, Mechanical ventilation, Intensive Care Unit (ICU)