Effect of EIT-guided PEEP Titration on the Prognosis of Patients With Moderate to Severe ARDS

Study Overview
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Brief Summary
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Acute respiratory syndrome distress (ARDS) is a clinical common syndrome with high mortality. Mechanical ventilation (MV) is the cornerstone of management of ARDS but can lead to ventilator-induced lung injury. Positive end-expiratory pressure (PEEP), as one of main component of MV, has been widely used in the clinical practice. However, the PEEP selection is still a difficult problem for moderate to severe ARDS patients. EIT, an imaging tool evaluating the regional ventilation distribution at the bedside, can achieve the individual PEEP selection for all mechanically ventilated patients. This article compared the effect of PEEP titrated guided by EIT with fraction of inspired oxygen (FiO2)-PEEP table on the clinical outcomes.

Detailed Description
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This is a prospective, multicenter, single-blind, parallel-group, adaptive randomized controlled trial (RCT) with intention-to-treat analysis which aims to determine the effects of PEEP setting guided by EIT on the clinical outcomes for moderate or severe ARDS patients ventilated with lung protective ventilation strategy. Adult patients with moderate to severe ARDS less than 72 hours after diagnosis will be included in this study. Patients in the intervention group will receive PEEP titrated by EIT with a stepwise decrease PEEP trial, whereas patients in the control group will select PEEP based on the FiO2-PEEP table. Other ventilator parameters will be set according to the ARDSnet strategy. The primary outcome is 28-day mortality. The secondary outcomes include ventilator-free days and shock-free days at day 28, length of ICU and hospital stay, the rate of successful weaning, proportion requiring rescue therapies, compilations, respiratory variables, and Sequential Organ Failure Assessment (SOFA). This study will also perform the interim analysis and subgroup analysis.

Official Title
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Effect of EIT-guided PEEP Titration on the Prognosis of Patients With Moderate to Severe ARDS

Conditions
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Clinical Outcomes

Intervention / Treatment
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* Device: electrical impedance tomography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age≥18 years Moderate-to-severe ARDS, defined by the ARDS Definition Task Force in the Berlin definition (partial pressure of arterial oxygen [PaO2]:FiO2 ratio ≤200 mmHg with a PEEP ≥5 cmH2O) Diagnosis of ARDS less than 72 hours Exclusion Criteria: Expected to be mechanically ventilated for less than 48 hours Severe chronic respiratory diseases requiring long-term home oxygen therapy or noninvasive MV Undrained pneumothorax or subcutaneous emphysema Undergoing extracorporeal membrane oxygenation (ECMO) before enrollment Contraindication to the use of EIT (pacemaker, automatic implantable cardioverter defibrillator, and implantable pumps) Severe neuromuscular disease Hemodynamic instability Contraindications to hypercapnia, such as intracranial hypertension or acute coronary syndrome Severe other organs dysfunction with a low expected survival (7 days) or palliative care Solid organ or hematologic tumors with the expected survival time less than 30 days Participating in other clinical trials within 30 days Pregnancy Refusal to sign the informed consent

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Diagnostic
Allocation: Randomized
Intervention Model: Sequential Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: EIT-PEEP strategy<br>Patients will receive PEEP titrated by EIT with a stepwise decrease PEEP trial | Device: electrical impedance tomography<br>* PEEP titrated by EIT will be performed with a decremental trial at the enrollment. Right after completing RM, PEEP will be set to 20cmH2O and then reduced in steps of 2cmH2O from 20 to zero every 2min.<br>|
| Active Comparator: ARDSNet-PEEP strategy<br>PEEP will be set according to the low FiO2-PEEP table to keep the oxygenation goals: SpO2 between 88% and 95%, and PaO2 between 55mmHg and 80mmHg. | Device: electrical impedance tomography<br>* PEEP titrated by EIT will be performed with a decremental trial at the enrollment. Right after completing RM, PEEP will be set to 20cmH2O and then reduced in steps of 2cmH2O from 20 to zero every 2min.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 28-day mortality | mortality in Day 28 | at day 28 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| VFDs at day 28 | defined as the number of days between successful weaning from MV and day 28 after study enrollment | at day 28 | 
| Shock-free days at day 28 | Shock-free days at day 28 | at day 28 | 
| Length of ICU stay | the survival rate(survival/total) during ICU stay | up to 24 months | 
| Length of hospital stay | the survival rate(survival/total) during hospital stay | up to 24 months | 
| The rate of successful weaning | Proportion of people who are not dependent on ventilator ventilation | at day 28 | 
| Proportion requiring rescue therapies | Proportion of people who require rescue therapies | day 28 | 
| Rate of pneumothorax | Rate of pneumothorax | day 28 | 
| driving pressure | measurement as one index of respiratory compliance at day 0, 1, 2, 3, and 7 from enrollment | day 0, day 1, day 2, day 3, day 7 | 
| Sequential Organ Failure Assessment (SOFA) score at the time of enrollment | SOFA range from three to eight. The higher the score, the worse the prognosis | at the time of enrollment | 
| Blood pressure at day D1, 2, 3, and 7 from enrollment | Both systolic and diastolic pressure at day D1, 2, 3, and 7 from enrollment | up to 24 months | 
| respiratory rate | respiratory rate | up to 7 days | 
| number of shock and gastrointestinal hemorrhage | shock, and gastrointestinal hemorrhage | day 28 |