Ultra Protective Ventilation During Venoarterial Extracorporeal Membrane Oxygenation (UPV-ECMO)

Study Overview
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Brief Summary
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Mechanical ventilation, in spite of being a life-saving technique, can also induce lung injury (VILI) mediated by an inflammatory response, thus having a profound impact in the course of critically ill patients. Ventilatory strategies aimed to minimize this VILI have reduced mortality rates. Patients suffering cardiogenic pulmonary edema may need venoarterial extracorporeal oxygenation, at the same time they are being mechanically ventilated. The objective of this study is to analyze changes induced by the use of utraprotective ventilatory strategies in the inflammatory lung response of these patients and their impact on outcomes.

Detailed Description
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Mechanical ventilation is the cornerstone of the critically-ill patients support, providing better gas exchange conditions while respiratory muscles rest. Providing this life-support technique may be harmful on the lung tissue, last decades research efforts were focused on minimizing the ventilator-induced lung injury (VILI). Knowledge regarding the mechanisms of this injury has led to changes in the clinical practice, consisting on the application of positive end-expiratory pressure (PEEP) and the use of low tidal volumes, giving rise to the strategy known as protective ventilation. Moreover, the use of extracorporeal membrane oxygenation (ECMO) techniques contributes to maintaining an adequate gas exchange until lung damage resolution. A tidal volume in the range of 6 ml/Kg of ideal body weight, with a reasonable level of PEEP is the standard of care for patients with the ARDS. However, optimal levels of tidal volume and PEEP have not been completely established. On the other side, decreasing tidal volume below 6 ml/Kg faces its own problems. The role of the so-called ultraprotective approaches, in which extracorporeal support is required to reduce tidal volumes up to 3 ml/kg or less, although feasible, is currently under research. During venoarterial ECMO, blood is removed from the vessels and pumped through a circuit where is oxygenated and CO2 is removed; finally, the blood is returned to the arterial circulation. The development of new circuits and devices made this therapy become safer and more useful, improving outcomes so that its application has been widespread to many centers all over the world. One of the ECMO advantages is carbon dioxide removal, which allows reducing tidal volume below 6 ml/kg. Ultraprotective strategies with 3 ml/kg have demonstrated to be feasible, but the additional benefit of this strategy is to be demonstrated. Therefore, in this study, patients suffering cardiogenic pulmonary edema requiring ECMO and mechanical ventilation are submitted to an ultraprotective ventilator strategy. Lung inflammatory response is measured before and after the intervention, in order to evaluate its impact in this subset of patients.

Official Title
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Effect of Ultraprotective Ventilation on the Lung Inflammatory Response in Patients With Acute Pulmonary Edema Treated With Venoarterial Extracorporeal Oxygenation

Conditions
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Cardiogenic Pulmonary Edema, Ventilator-Induced Lung Injury, Extracorporeal Circulation; Complications

Intervention / Treatment
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* Device: Ultraprotective ventilation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Cardiogenic pulmonary edema supported by venoarterial extracorporeal membrane oxygenation. Invasive mechanical ventilatory support under sedation. Exclusion Criteria: Immunosupresion. Hemodynamic instability refractory to mechanical support, conditioning an end-of-life approach and terminal situation.

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: Supportive Care
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Recruited patients<br>Ultraprotective ventilation | Device: Ultraprotective ventilation<br>* Adjusting ventilator parameters for 3 ml/kg of tidal volume in order to achieve the ultra protective strategy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in lung inflammatory mediators levels | Bronchoalveolar lavage cytokines levels, measured in ng/ml | Baseline and 18 hours after the intervention |