a Bayesian Analysis of Three Randomised Clinical Trials of Intraoperative Ventilation

Study Overview
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Brief Summary
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The investigators designed a protocol for a Bayesian unplanned posthoc analysis using the pooled dataset from three large randomized clinical trials. The primary endpoint will be a composite of postoperative pulmonary complications (PPC) within the first seven postoperative days, which reflects the primary endpoint of the original studies. The investigators will carry out a reanalysis of the harmonised database using Bayesian statistics.

Detailed Description
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Background: Using the frequentist approach, a recent meta-analysis of three randomized clinical trials in patients undergoing intraoperative ventilation during general anesthesia for major surgery. failed to show the benefit of ventilation that uses high positive end expiratory pressure with recruitment maneuvers when compared to ventilation that uses low positive end-expiratory pressure without recruitment maneuvers. Methods: The investigators designed a protocol for a Bayesian analysis using the pooled dataset. The multilevel Bayesian logistic model will use the individual patient data. Prior distributions will be prespecified to represent a varying level of skepticism for the effect estimate. The primary endpoint will be a composite of postoperative pulmonary complications (PPC) within the first seven postoperative days, which reflects the primary endpoint of the original studies. The investigators preset a range of practical equivalence to assess the futility of the intervention with an interval of odds ratio (OR) between 0.9 and 1.1 and assess how much of the 95% of highest density interval (HDI) falls between the region of practical equivalence.

Official Title
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Effect of Intraoperative PEEP With Recruitment Manoeuvres on the Occurrence of Postoperative Pulmonary Complications During General Anaesthesia--a Bayesian Analysis of Three Randomised Clinical Trials of Intraoperative Ventilation

Conditions
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Mechanical Ventilation Complication, Surgery, Pulmonary Complication, Postoperative Complications

Intervention / Treatment
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* Other: High PEEP + Recruitment maneuvers


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Planned for major surgery At risk for pulmonary complications Exclusion Criteria: Planned thoracic surgery . Unscheduled surgery (i.e., urgent, or emergent surgeries)

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 + Recruitment Maneuvers<br>Patients who received intraoperatively high PEEP (10-12 cmH2O) after a recruitment maneuvers as per the original study protocol | Other: High PEEP + Recruitment maneuvers<br>* The use of a High PEEP (positive end-expiratory pressure) level after recruiting collapsed alveoli can protect from mechanical ventilation associated lung injury<br>|
| Standard PEEP<br>Patients who received intraoperatively standard PEEP (0-5 cmH2O) without recruitment maneuvers | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of postoperative pulmonary complications |  | 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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Mechanical ventilation,, Bayesian analysis, PEEP, Recruitment Maneuvers, Intraoperative Mechanical Ventilation, Postoperative complications, Perioperative medicine