Airway Pressure Release Ventilation (APRV) Protocol Early Used in Acute Respiratory Distress Syndrome

Study Overview
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Brief Summary
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The aim of this study is to assess the effects and safety of the early application of BILEVEL-APRV protocol and conventional ventilation strategy that used low tidal volume and adequate PEEP level in ARDS patients .

Detailed Description
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Although mechanical ventilation is life-sustaining for patients with ARDS, it can perpetuate lung injury. A number of recent advances have greatly improved in the mechanical ventilation strategies and treatment for acute respiratory distress syndrome (ARDS), however, Mortality remains high, even with the use of low tidal volume and adequate positive end expiratory pressure(PEEP). Numerous experimental showed that the BILEVEL-APRV mode used in animal ARDS model can improve gas exchanges and hemodynamic tolerance of the ventilation while reducing the dosage for sedative drugs. The aim of this single-center, prospective, randomized, controlled, open study is to compare the effects and safety of the early application of BILEVEL-APRV protocol and conventional ventilation strategy that used low tidal volume and adequate PEEP level in ARDS patients .

Official Title
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the Effects and Safety of the Early Application of Bi-level Airway Pressure Ventilation-airway Pressure Release Ventilation(BILEVEL-APRV) Protocol and Conventional Ventilation Strategy Were Compared in ARDS Patients

Conditions
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Acute Respiratory Distress Syndrome

Intervention / Treatment
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* Device: Nellcor Puritan Bennett 840 ventilator system


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Acute respiratory distress syndrome,according to the Berlin definition of ARDS, - The receipt of endotracheal mechanical ventilation for a period was no longer than 48 hours A ratio of the partial pressure of arterial oxygen (PaO2) to the fraction of inspired oxygen(FiO2) was less than 250. Exclusion Criteria: Pregnancy The expected duration of mechanical ventilation was less than 48 hours Intracranial hypertension (suspected or confirmed) Neuromuscular disorders that are known to prolong the need for mechanical ventilation Known or suspected chronic obstructive pulmonary disease(COPD) Preexisting conditions with an expected 6-month mortality exceeding 50% Pneumothorax (drained or not)at enrollment Treatment with extracorporeal support (ECMO) at enrollment There was a lack of commitment to life support.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: conventional ventilation strategy<br>The conventional ventilation strategy use volume-controlled ventilation (VCV) or pressure-controlled ventilation (PCV) mode, combination with low tidal volume and adequate PEEP level. | Device: Nellcor Puritan Bennett 840 ventilator system<br>* Puritan Bennett 840 ventilator can provide the VCV,PCV,Bi-level Airway Pressure Ventilation-airway Pressure Release Ventilation(BILEVER-APRV) mode.<br>|
| Experimental: BILEVEL-APRV protocol<br>According to our BILEVEL-APRV protocol, BILEVEL-APRV APRV mode with specific settings,combination with spontaneous breathing. | Device: Nellcor Puritan Bennett 840 ventilator system<br>* Puritan Bennett 840 ventilator can provide the VCV,PCV,Bi-level Airway Pressure Ventilation-airway Pressure Release Ventilation(BILEVER-APRV) mode.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mechanical ventilation free days |  | day 28 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| all causes mortality | Participants will be followed for the duration of ICU stay | day 60 | 
| all cause hospital mortality | Participants will be followed for the duration of hospital stay, until day 60 maximum. | day 60 | 
| Duration of stay in ICU |  | day 60 | 
| Duration of hospital stay |  | day 60 | 
| peak airway pressure,mean airway pressure,positive end expiratory pressure(cmH2O) |  | day 7 | 
| Average dosage of sedative infusion |  | day 7 | 
| Richmond Sedation-Agitation Scale |  | day 7 | 
| Average dosage of vasoactive drugs each day in use |  | day 7 | 
| number of patients requiring cointerventions and Adjunctive Therapies |  | Day 28 | 
| number of patients requiring the use of noninvasive ventilation |  | Day 28 | 
| the tracheotomy rate |  | Day 28 | 
| Number of patients with a pneumothorax |  | Day 28 | 
| the number of days free from organ dysfunction |  | Day 28 | 
| tidal volume(ml) |  | Day 7 | 
| static lung compliance（ml/cmH2O） |  | Day 7 | 
| PaO2,PaCO2(mmHg) |  | Day 7 | 
| Blood pressure(mmHg) |  | Day 7 | 
| blood lactic acid（mmol/l） |  | Day 7 | 
| minute ventilation (L) |  | Day 7 |