Re-Evaluation of the Effects of High PEEP During General Anesthesia For Surgery (REPEAT)

Study Overview
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Brief Summary
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Aiming to understand the isolated impact of high PEEP in patients undergoing mechanical ventilation for general anesthesia for surgery, three appropriately sized international multicentre randomized controlled trials have been performed over recent years: the 'PROtective Ventilation using HIgh versus LOw PEEP trial (PROVHILO), the 'individualized PeRioperative Open-lung Ventilation trial' (iPROVE), and the 'Protective intraoperative ventilation with higher versus lower levels of positive end-expiratory pressure in obese patients trial' (PROBESE). These three trials had several similarities in key areas of their study protocols, inclusion and exclusion criteria, and collected data, and even the primary and secondary outcomes. Of note, the three trials combined high PEEP with recruitment manoeuvres. This allows an individual patient data meta-analysis.

Official Title
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Re-Evaluation of the Effects of High PEEP During General Anesthesia For Surgery - An Individual Patient Data Meta-Analysis of PROVHILO, iPROVE and PROBESE

Conditions
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Surgery, Mechanical Ventilation Complication, Pulmonary Complication

Intervention / Treatment
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* Behavioral: High PEEP
* Behavioral: Low PEEP


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Enrolled into one of the three studies (PROVHILO, iPROVE or PROBESE) to either high PEEP or low PEEP

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| High PEEP<br>Use of high levels of PEEP with recruitment maneuvers | Behavioral: High PEEP<br>* Use of high levels of PEEP combined with recruitment maneuvers and low tidal volume ventilation during general anesthesia<br>|
| Low PEEP<br>Use of low levels of PEEP without recruitment maneuvers | Behavioral: Low PEEP<br>* Use of low levels of PEEP without recruitment maneuvers and low tidal volume ventilation during general anesthesia<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of postoperative pulmonary complications | Collapsed composite of complications developing within the first seven postoperative days, including: Mild respiratory failure; or Severe respiratory failure; or Acute Respiratory Distress Syndrome (ARDS); or Pulmonary infection; or Pleural effusion; or Atelectasis; or Pneumothorax; or Bronchospasm. | Until day seven or hospital discharge, whichever comes first | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of severe postoperative pulmonary complications | Collapsed composite of complications developing within the first seven postoperative days, including: Severe respiratory failure; or Acute Respiratory Distress Syndrome (ARDS); or Pulmonary infection; or Pleural effusion; or Atelectasis; or Pneumothorax; or Bronchospasm | Until day seven or hospital discharge, whichever comes first | 
| Incidence of extrapulmonary pulmonary complications | Collapsed composite of complications developing within the first seven postoperative days, including: Systemic Response Inflammatory Syndrome; or Sepsis; or Septic Shock; or Acute Kidney Injury. | Until day seven or hospital discharge, whichever comes first | 
| Incidence of intraoperative complications | Defined as intraoperative hypotension; or need for rescue for desaturations; or need for vasoactive drugs. | Intraoperatively | 
| Incidence of intensive care unit admission | Incidence of intensive care unit admission during hospital stay | Until hospital discharge, death or 100 days, whichever comes first | 
| Hospital length of stay | Duration of hospital length of stay in days | Until hospital discharge, death or 100 days, whichever comes first | 
| Incidence of 7-day mortality | Mortality during the first seven days of hospitalization | Until day seven or hospital discharge, whichever comes first | 
| Incidence of in-hospital mortality | Mortality during hospitalization | Until hospital discharge, death or 100 days, whichever comes first | 
| Incidence of major postoperative complications | Collapsed composite of complications developing within the first seven postoperative combining severe postoperative pulmonary complications, sepsis, septic shock and/or acute kidney injury) | Until day seven or hospital discharge, whichever comes first | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Surgery, Mechanical ventilation, PEEP, Postoperative pulmonary complications, Individual patient data meta-analysis