A Comparison of Optimal PEEP Determination Guided by EIT and Conventional Protective Ventilation Tool in ARDS Patients

Study Overview
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Brief Summary
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The study of positive end-expiratory pressure(PEEP) in the setting mode has not yet been conclusive. there are several ways to choose the best positive end-expiratory pressure(PEEP) mode for ARDS patients. In this study ,the investigators selected two best positive end-expiratory pressure(PEEP) assessment methods to compare: First is using the conventional postive ventilator to choose positive end-expiratory pressure(PEEP) and the new non-invasive electrical impedance tomography(EIT) guided method and evaluation the treatment outcome in moderate and severe acute respiratory distress syndrome patients by using pressure-volume curve guided and electrical impedance tomography guided positive end-expiratory pressure setting. In this project, we utilize a newly available non-invasive method- electric impedance tomography (EIT) and Protective Ventilation to determine the optimal PEEP on ARDS patients required invasive mechanical ventilator support at a medical center medical ICU (MICU) and cardiovascular ICU (CVICU)- the Far Eastern memorial hospital, Taiwan.

Detailed Description
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Acute respiratory distress syndrome (ARDS)，over the years in the treatment policy has been confirmed that: with low tidal volume to achieve lung protection strategy and high positive end-expiratory pressure (PEEP), both can effectively reduce the mortality rate. And increase PEEP，the alveolar pressure is greater than the atmospheric pressure when exhaled，So that can be effective expansion of the lungs to avoid spitting at the end of the alveolar collapse. The study of PEEP in the setting mode has not yet been conclusive. Currently in the clinical situation，there are several ways to choose the best PEEP mode for ARDS patients. In this study the investigators selected two best PEEP assessment methods to compare: First is using the conventional postive ventilator to choose optimal and the new non-invasive electrical impedance tomography guided method and evaluation the treatment outcome in moderate and severe acute respiratory distress syndrome patients by using pressure-volume curve guided and electrical impedance tomography guided positive end-expiratory pressure setting. In this project, the investigators utilize a newly available non-invasive method- electric impedance tomography (EIT) and Protective Ventilation to determine the optimal PEEP on ARDS patients required invasive mechanical ventilator support in ICU at the Far Eastern memorial hospital, Taiwan.

Official Title
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A Comparison of Optimal Positive End Expiratory Pressure Determination Guided by Electrical Impedance Tomography and Conventional Protective Ventilation Tool in Acute Respiratory Distress Syndrome Patients

Conditions
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ARDS, Acute Respiratory Distress Syndrome

Intervention / Treatment
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* Device: Ventiltor P/V Loop
* Device: Electrical Impedance Tomography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Moderate to severe ARDS patient on mechanical ventilation from ER or word transfer ICU. (P/F≦ 200 with PEEP ≥ 5cmH20) (PEEP greater than or equal to 5 cm H2O and Berlin criteria for ARDS) Exclusion Criteria: On pacemaker Pregnant Thoracic or spinal cord trauma Pneumothorax Hemodynamic instability IICP

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 99 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
Interventional Model Description: Moderate to severe ARDS patient on mechanical ventilation from ER or word transfer ICU.(P/F≦200+PEEP≧ 5cmH20)
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Control group_Use Ventilator P/V tool<br>Use the Pressure/Volume Loop | Device: Ventiltor P/V Loop<br>* determine the Optimal PEEP and keep 48hr on ARDS patients<br>|
| Active Comparator: Study group_Use EIT<br>Use the Electrical Impedance Tomography | Device: Electrical Impedance Tomography<br>* determine Optimal PEEP and keep 48hr on ARDS patients<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Compare the survival rate between two groups | Calculate the survival rate | Compare the survival rate between two groups during 91 days in hospitalization | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Oxygention improve rate in the hospital | Calculate PaO2/FiO2 ratio improvement rate in the hospital | Compare the PaO2/FiO2 ratio after fixed Optimal PEEP 48hrs later | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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PEEP, ARDS, Acute Respiratory Distress Syndrome, pressure-volume loop, Positive End-Expiratory Pressure, hysteresis