Impact of Proportional Assisted Ventilation on Dyspnea and Asynchrony in Mechanically Ventilated Patients (DYS-PAV)
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|ClinicalTrials.gov Identifier: NCT02801994|
Recruitment Status : Recruiting
First Posted : June 16, 2016
Last Update Posted : April 26, 2019
Rational. The mismatch between the activity of the respiratory muscles and the assistance delivered by the ventilator results in patient-ventilator disharmony, which is commonly observed in ICU patients and is associated with dyspnea and patient-ventilator asynchrony. Both dyspnea and asynchrony are in turn associated with a worse prognosis. Unlike conventional modes of mechanical ventilation, such as pressure support ventilation (PSV) that deliver a constant level of assistance regardless of the patient effort, Proportional Assisted Ventilation (PAV) adjusts the level of ventilator assistance to the activity of respiratory muscles. To date, data on the impact of PAV on dyspnea and patient ventilator asynchrony are scarce and most studies have been conducted in healthy subjects or in ICU patients who had no severe dyspnea nor severe asynchrony. To our knowledge, there are no data in patients with severe patient-ventilator dysharmony.
Study Aim. To evaluate the impact of PAV on dyspnea and patient-ventilator asynchrony in ICU mechanically ventilated patients in intensive care with severe patient-ventilator disharmony defined as either severe dyspnea or severe patient-ventilator asynchrony.
Patients and Methods. Will be included 24 ICU mechanically ventilated patient exhibiting severe patient-ventilator dysharmony with PSV. The intensity of dyspnea will be assessed by the VAS, the ICRDOSS and by the electromyogram of extradiaphragmatic inspiratory muscles and pre inspiratory potential collected from the electroencephalogram. The prevalence of patient-ventilator asynchrony will be quantified.
Expected results. It is anticipated that the switch from PSV to PAV will decrease the prevalence and severity of dyspnea and the prevalence of patient-ventilator asynchrony.
|Condition or disease||Intervention/treatment||Phase|
|Dyspnea||Device: PAV, Puritan Bennett 980 ventilator||Not Applicable|
|Study Type :||Interventional (Clinical Trial)|
|Estimated Enrollment :||30 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Official Title:||Impact of Proportional Assisted Ventilation on Dyspnea and Asynchrony in Mechanically Ventilated Patients|
|Actual Study Start Date :||February 24, 2016|
|Estimated Primary Completion Date :||October 2019|
|Estimated Study Completion Date :||October 2019|
Experimental: Ventilator settings, PAV
A first 30-minutes recording in PSV will be performed. Dyspnea-VAS, IC-RDOS will be measured at the beginning and at the end of this period. EMG and EEG will be recorded continuously. Patients will be subsequently switched to PAV.
The PAV mode will be delivered by Puritan Bennett 980 ventilator (Covidien, Boulder, USA). Levels of PEEP and FiO2 will be kept constant. The level of assistance in PAV, named %-assistance will be set in order to keep the patient in a respiratory effort zone corresponding to a respiratory muscles pressure time product (PTPmus) between 50 and 150 cm H2O • s / min.
Device: PAV, Puritan Bennett 980 ventilator
The PAV mode will be delivered by Puritan Bennett 980 ventilator (Covidien, Boulder, USA). Levels of PEEP and FiO2 will be kept constant. The level of assistance in PAV, named %-assistance will be set in order to keep the patient in a respiratory effort zone corresponding to a respiratory muscles pressure time product (PTPmus) between 50 and 150 cm H2O • s / min. As it is not possible to calculate directly the PTPmus at bedside, the investigators will use as a substitute its main component, the pressure peak muscle of the airways according to the previous report from Carteaux et al. This setting has been described extensively and its use has been the subject of a feasibility study in 50 patients. After a 20-minutes stabilization period, a 30-minutes recording will be performed.
- Quantification of dyspnea [ Time Frame: in real time, during the procedure ]Dyspnea will be quantified with with the ICU Respiratory Distress Operating Scale (IC-RDOS)
- Airway pressure [ Time Frame: in real time, during the procedure ]The airway pressure will be also measured at the Y-piece by a differential pressure transducer (Validyne, Northridge, USA).
- Electromyography (EMG) of extra inspiratory diaphragmatic muscles [ Time Frame: in real time, during the procedure ]The amplitude of the EMG signal of extradiaphragmatics inspiratory muscles is proportional to the intensity of dyspnea. EMG will be collected by self-adhesive surface electrodes of the same type as those commonly used to collect the ECG signal in critically ill patients. A distance of 2 cm will separate the two electrodes. The position of the electrodes will depend on the recorded muscle.
- Electroencephalogram (EEG) in search of a pre-inspiratory potential [ Time Frame: in real time, during the procedure ]The application of an inspiratory resistive load to healthy subjects results in the activation of the pre-motor cortex detected by EEG recording. This EEG activity is named pre-inspiratory potential (PIP).
- Arterial blood gas [ Time Frame: in real time, during the procedure ]For patients with an arterial catheter, the measurement of blood gases using an arterial blood sample of a volume of less than 1ml be performed at the end of each condition.
- Patient-ventilator asynchrony [ Time Frame: in real time, during the procedure ]Asynchrony will be detected by visual inspection of the recordings. The investigators will investigate patterns of two major asynchronies that are easily detected on pressure and flow recordings: ineffective triggering and double triggering. Ineffective triggering will be defined as an abrupt airway pressure drop (≥ 0.5 cmH2O) simultaneous to a flow decrease (in absolute value) and not followed by an assisted cycle during the expiratory period. Double-triggering will be defined as two cycles separated by a very short expiratory time, defined as less than one-half of the mean inspiratory time, the first cycle being patient-triggered.
- Flow [ Time Frame: in real time, during the procedure ]Airway flow will be measured with a pneumotachograph (Hans Rudolph, Kansas City, USA) inserted between the Y-piece and the endotracheal tube and connected to a differential pressure sensor (Validyne, Northridge, USA).
- Quantification of dyspnea [ Time Frame: in real time, during the procedure ]Dyspnea will be quantified with a dyspnea-VAS from 0 (no discomfort) to 10 (maximum breathing)
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02801994
|Service de Pneumologie et Réanimation Médicale, Groupe Hospitalier Pitié Salpêtrière||Recruiting|
|Paris, France, 75013|
|Contact: Alexandre Demoule, MD, PhD +33142167761 firstname.lastname@example.org|
|Contact: Côme Bureau, Resident +33676037129 email@example.com|