Variable Pressure Support Trial

Study Overview
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Brief Summary
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In 2008 a new ventilation strategy termed variable Pressure Support ventilation (PSV) was introduced, which is able to increase the variability of the respiratory pattern independent from the inspiratory effort. In experimental lung injury, variable PSV was found to improve gas exchange and decrease the inspiratory effort, while reducing alveolar edema and inflammatory infiltration compared to conventional(non-variable) PSV. Importantly, variable PSV reduced peak airway pressure and respiratory system elastance in a variability dependent manner.In addition, preliminary observations suggest that variable PSV can reduce the work of breathing and improve patient comfort, but it is not known whether this new ventilatory strategy is able to speed the weaning from mechanical ventilation. Since variable PSV can reduce the mean pressure support, it may lead to a faster reduction of pressure support and, therefore, a shorter weaning period than conventional PSV. The hypothesis of this study is that variable pressure support ventilation reduces the duration of mechanical ventilation to non-variable (conventional) pressure support ventilation.

Official Title
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International Multicenter Randomized Controlled Open Trial on Variable vs. Non-Variable Pressure Support for Weaning From Mechanical Ventilation

Conditions
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Acute Lung Injury, Adult Respiratory Distress Syndrome, at Least 24 h of Controlled Mechanical Ventilation

Intervention / Treatment
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* Other: Variable Ventilation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years Duration of controlled mechanical ventilation ≥ 24h Availability of a Infinity V500 ventilator (ready to use) Informed consent according to local regulations Temperature ≤ 39 °C Hemoglobin ≥ 6 g/dl PaO2/FIO2 ≥ 150 mmHg with positive end-expiratory pressure (PEEP) ≤16 cmH2O Ability to breath spontaneously Exclusion Criteria: Participation in another interventional trial within the last four weeks before enrollment in this trial Peripheral neurological disease associated with impairment of the respiratory pump Muscular disease associated with impairment of the respiratory pump Instable thorax with paradoxical chest wall movement Planned surgery under general anesthesia within 72 hours Difficult airway/intubation Existing tracheotomy at ICU admission Expected survival < 72 hours Home mechanical ventilation or on chronic oxygen therapy Suspected 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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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: Variable Ventilation<br>Patients are ventilated with variable pressure support mode. | Other: Variable Ventilation<br> <br> |
| No Intervention: Conventional (non-variable) Ventilation<br>Patients are ventilated with non-variable(conventional) pressure support ventilation mode. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weaning time | Weaning time defined as time from randomization to successful extubation. | From time of randomization until the time of successful extubation, estimated to be up to 30 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Acute Lung Injury, Adult Respiratory Distress Syndrome, Interactive Ventilatory Support, Positive-Pressure Respiration, Ventilator-Induced Lung Injury