VARIABLE-PSV Study

Study Overview
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Brief Summary
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Variable PSV is a new ventilatory mode which delivered a pressure support variable from 0 to 100% variation of the set PSV level.This study aimed to compare the ventilatory behavior, sleep quality and gas exchange between VARIABLE (or Noisy)-PSV and standard (or fixed)-PSV during the weaning phase of critically ill patients who required mechanical ventilation.

Detailed Description
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Twenty patients will be enrolled. They will be ventilated withVARIABLE-PSV and STANDARD-PSV: for 24 h each in a randomized crossover order. The ventilatory parameters, ventilator/patient asynchrony, gas exchange effects, sleep quality and ventilatory comfort produced by the two ventilation modes will be compared. Before randomisation, a sequence of VARIABLE-PSV will be performed with different level of variation setting to better define the future behavior of the patient under this mode during the 24 h of Variable-PSV.

Official Title
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Evaluation a New Ventilatory Modes: VARIABLE-PSV: a Randomized Controlled Cross-over Study: the  VARIABLE-PSV Study

Conditions
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Acute Respiratory Failure, Critical Illness, Ventilation Weaning

Intervention / Treatment
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* Other: VARIABLE-PSV ventilatory mode
* Other: STANDARD-PSV ventilatory mode


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ventilation planned for more than 48 h patient alert and calm corresponding to a Richmond Agitation-Sedation Scale (RASS) between -2 and 0 Age > or equal 18 Surrogate decision maker's consent Exclusion Criteria: Clinical instability for any reason. Life support withdrawal code Patient under tutelage Pregnancy No French health insurance

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: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: VARIABLE-PSV ventilatory mode<br> | Other: VARIABLE-PSV ventilatory mode<br>* The two ventilatory modes will be studied during 24h in intubated patients in random order.<br>|
| Other: STANDARD-PSV ventilatory mode<br> | Other: STANDARD-PSV ventilatory mode<br>* The two ventilatory modes will be studied during 24h in intubated patients in random order.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Oxygenation in each ventilatory mode | We will performed arterial blood gases and oxygenation wil be evaluated by the PaO2/FiO2 ration. | after 24h of mechanical ventilation in each mode | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ventilatory comfort | Comfort zone is defined as previously reported in some papers as considered adequate ventilation : 6 < tidal volume < 10 ml/kg, ETCO2 < 55 mmHg and < 65 mmHg for COPD patients and 12 < Respiratory rate < 35 cycles/min. | during 24h in each mode | 
| Feasibility | Evaluation of time spent in each mode during the 24 hours of ventilation without any side effects and switch for another ventilatory mode. | during the 24 hours | 
| Patient/ventilator asynchronism | Evaluation of number of asynchrony evaluated by an Asynchrony Index (AI) in each mode during the 24 hours of mechanical ventilation | during the 24 hours | 
| Ventilatory effects | Evaluation of machine ventilatory behaviors in each mode during the 24 hours of mechanical ventilation. | during the 24 hours | 
| Sleep quality | Evaluation of quality of sleep in each mode after the 24h of mechanical ventilation | after the 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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PSV, Acute respiratory failure, Critical illness, Mechanical ventilation, Ventilation weaning, Intensive Care Unit, Variable (NOISY) PSV