Open Lung Protective Ventilation in Cardiac Surgery

Study Overview
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Brief Summary
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Cardiac surgery with cardiopulmonary bypass (CPB) frequently induces post-operative respiratory dysfunction. The post-operative pulmonary complications (PPCs) significantly increase the peri-operative morbidity and require invasive treatments during longer and more expensive ICU stays. A specific pathophysiology involving general anesthesia and CPB-related factors (inflammation, pulmonary ischemia) has been clearly demonstrated and pulmonary atelectasis seems to play a central role in the occurence of these PPCs. The open lung approach is a ventilation strategy that aims to open the lung and keep it open using different ventilatory settings. The efficacy of that strategy is not demonstrated in the global surgical population. However, its application in the perioperative care of cardiac surgery patients could be of great interest by counteracting the development of atelectasis. The purpose of this multicentre, double blinded, randomized controlled study is to evaluate the influence of a perioperative multimodal protective ventilation strategy based on the open lung approach on postoperative outcomes during the first 7 days following cardiac surgery. Participating centres will include 500 adult patients undergoing scheduled on-pump cardiac surgery. The open lung approach will combine recruitment maneuvers (RM), positive end expiratory pressure (PEEP) at 8 cmH2O from intubation to detubation and continuation of ultraprotective ventilation during CPB. It will be compared to a conventional approach without RM, with PEEP at 2 cmH2O and discontinuation of ventilation during CPB. The primary endpoint is any post-operative pulmonary complication. The secondary endpoints are any post-operative extra-pulmonary complications and the number of ICU-free days to day 7.

Official Title
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Open Lung Protective Ventilation During Cardiac Surgery With Cardiopulmonary Bypass : a Randomized Controlled Trial

Conditions
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Hypoxemia

Intervention / Treatment
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* Procedure: Open lung protective ventilation strategy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Cardiac surgery planned with CPB and sternotomy. Age > 18 years old. Exclusion Criteria: Urgent surgery : cardiac transplantation, aortic dissection, active endocarditis. Aortic arch surgery with circulatory arrest. LVAD surgery. Acute or chronic preoperative hypoxemia (PaO2 < 65 mmHg in air). Preoperative shock state requiring catecholamines. LVEF < 40%. Pulmonary hypertension with systolic pulmonary artery pressure > 50 mmHg. Severe right ventricular dysfunction (TDI tricuspid annular systolic velocity < 10 cm.s-1). Chronic kidney disease (Glomerular filtration rate < 30 mL/min). Body Mass Index > 35kg/m2. Patient's refusal.

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: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Open lung protective ventilation<br>Recruitment maneuvers (30 cmH2O during 30 seconds) after intubation, after CPB initiation, before aortic declamping and at ICU arrival. PEEP at 8 cmH2O. Ultraprotective ventilation during CPB: PEEP 8 cmH2O, Tidal volume 3mL/kg, Respiratory rate 12 cycles per minute, FiO2 40%. Assigned intervention - Procedure: patients are randomized and ventilated with the open lung strategy from intubation to detubation. | Procedure: Open lung protective ventilation strategy<br> <br> |
| No Intervention: Conventional strategy<br>No recruitment maneuvers. PEEP at 2 cmH2O. During CPB: continuous positive pressure at 2 cmH2O. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Post-operative pulmonary complications defined as a composite endpoint | Mild hypoxemia Moderate hypoxemia Severe hypoxemia Severe bronchospam Radiological atelectasis Respiratory acidosis Pneumonia Pleural effusion Acute Respiratory Distress Syndrome Need for reintubation Need for reintubation | first 7 days post-operatively. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative extrapulmonary complication | Systemic inflammatory response syndrome Sepsis Septic chock Mediastinitis Pericardial tamponade Surgical bleeding Acute kidney failure (KDIGO stage 2 or 3) Postoperative atrial fibrillation Cardiogenic chock Delirium | First 7 days post operatively | 
| ICU free Days | Days alive and free from the need of intensive care | First 7 days post operatively |