Effect of Intraoperative PEEP Individualization According to Driving Pressure in Major Abdominal Surgery

Study Overview
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Brief Summary
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In this prospective, randomized trial, including patients scheduled for a major open or laparoscopic abdominal surgery (duration >2 hours) under general anesthesia , the investigators will compare 2 strategies of protective mechanical ventilation: a fixed intraoperative PEEP of 6 cmH2O and an individualized intraoperative PEEP according to the driving pressure.

Detailed Description
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Patients will be randomized into 2 groups: Fixed PEEP group: will receive protective intraoperative mechanical ventilation: tidal volume: 6 ml/kg of PBW, recruitment maneuvers every immediately after tracheal intubation and every 2 hours and a fixed PEEP of 6 cmH2O Individualized PEEP: protective mechanical ventilation with the same modality with an individualization of PEEP levels hourly in order to achieve the lowest driving pressure. PEEP levels will be adjusted after intubation and hourly by increasing or decreasing PEEP levels every 10 respiratory cycles. The primary outcome: incidence of post operative pulmonary complications during the first post operative days.

Official Title
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Effect of Intraoperative PEEP Individualization According to Driving Pressure in Major Abdominal Surgery

Conditions
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Mechanical Ventilation Complication

Intervention / Treatment
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* Procedure: Peep individualization


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI<35, ARISCAT score > 26, patients scheduled for major abdominal surgery Exclusion Criteria: unplanned post operative ICU stay and mechanical ventilation

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Fixed PEEP group<br>Protective intraoperative ventilation with: 6 ml/kg IBW tidal volume recruitment maneuver and fixed PEEP¨level of 6 cmH2O | |
| Experimental: Individualized PEEP group<br>Protective intraoperative ventilation with: 6 ml/kg IBW tidal volume recruitment maneuver and individualized PEEP¨level in order to achieve the lowest driving pressure | Procedure: Peep individualization<br>* Intraoperative Peep individualization in order to achieve the lowest driving pressure<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| incidence of pulmonary post operative complications | SpO2< 92%, new chest Xray infiltrates, acute respiratory failure requiring intervention | first 7 post operative days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| lung aeration score (LAS) | assessment LAS with lung ultrasound minimum 0 maximum: 36 (worse outcome) | day 1, day 3 and day 7 after surgery |