Electrical Impedance Tomography Guided Assessment of Optimum PEEP Levels During Mechanical Ventilation in Lateral Decubitus Position

Study Overview
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Brief Summary
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Goal of this study is to determine optimal PEEP levels for patients undergoing surgery in lateral decubitus position. Patients will be randomized into 3 groups - PEEP 0, 5 and 10 mbar. Endotracheal anesthesia will be conducted with propofol, fentanyl, rocuronium and sevoflurane/O2/air gas mixture. Patients with preexisting lung disease, organ transplants and disseminated malignant disease will be excluded. Demographic data - age, weight, height, ASA status, smoking history will be recorded. EIT measured parameters - tidal variation ratio of nondependent and dependent lung, regional end-tidal and end-expiratory lung impedances as well as horizontal and vertical centers of ventilation will be recorded and calculated at 3 time points - before anesthesia induction, 5 minutes after lateral positioning of the patient and 90 minutes after lateral positioning. ABGs will be sampled to calculate aA gradient and Horovitz quotient at those time points as well as measured hemodynamic parameters (HR, BP, CI, SVI). Primary endpoints for the study are nondependent/dependent tidal variation ratios measured at predefined time points and changes in ABGs. Secondary endpoints are number of postoperative pulmonary complications (defined as new onset of pneumonia during 28 days of followup), length of hospital stay and changes in hemodynamic parameters.

Official Title
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Electrical Impedance Tomography Guided Assessment of Optimum PEEP Levels During Mechanical Ventilation in Lateral Decubitus Position

Conditions
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Mechanical Ventilation, Bioelectrical Impedance

Intervention / Treatment
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* Procedure: PEEP level


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients scheduled for nephrectomy, adrenalectomy or urterotomy surgery which will be performed in lateral decubitus position signed informed consent form Exclusion Criteria: preexisting moderate to severe obstructive (GOLD score > 1) or restrictive lung disease (FVC < 85%) history of organ transplant disseminated malignant disease pregnancy

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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Accepts Healthy Volunteers

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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: PEEP 5<br> | Procedure: PEEP level<br>* Patients will have variable PEEP levels and will be monitored<br>|
| Active Comparator: PEEP 0<br> | Procedure: PEEP level<br>* Patients will have variable PEEP levels and will be monitored<br>|
| Experimental: PEEP 10<br> | Procedure: PEEP level<br>* Patients will have variable PEEP levels and will be monitored<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of nondependent / dependent tidal variation | Measured by EIT | Baseline, 10 and 90 minutes post lateral positioning | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of a-A gradient | Measured by ABG analysis | Baseline, 10 and 90 minutes post lateral positioning | 
| Duration of hospital stay | Between groups | Up to 28 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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PEEP, Electrical impedance tomography, Mechanical ventialtion