MedPath

Ventilation Strategies During Spontaneous Breathing Trial

Not Applicable
Completed
Conditions
Acute Respiratory Insufficiency
Interventions
Procedure: ATC then pressure support 7 cm H2O PEP 4 cm H2O
Procedure: Pressure support 7 cm H2O PEP 4 cm H2O then ATC
Registration Number
NCT02939963
Lead Sponsor
Hospices Civils de Lyon
Brief Summary

Patients who are intubated and mechanically ventilated for acute respiratory failure in the Intensive Care Unit (ICU) are at some point eligible for weaning. The common way to wean them from mechanical ventilation is to screen criteria for feasibility and, if present, to test feasibility by performing spontaneous breathing trial. This latter can be done either by setting a low pressure support level (expected to compensate the airflow resistance due to endotracheal tube) or by allowing the patient to breathe spontaneously through the tube without any support from the ventilator. Combination of low pressure assistance strategy (7 cm H2O) and positive expiratory pressure (PEP) of 4 cm H2O is the strategy used in our unit. Such a low pressure support level should actually result in a real assistance and, hence this is not the real spontaneous breathing capacity that is tested. Some ICU ventilators offer the option of compensating for the airflow resistance due to endotracheal tube, automatic tube compensation (ATC). Therefore, investigators aimed at comparing in patients ready to wean the usual procedure in our ICU and the ATC mode. In the ATC arm, the patients are breathing spontaneously through the endotracheal tube and are connected to the ventilator set at inspiratory pressure support of 0 cm H2O, PEP 4 cm H2O and ATC on.

Two parallel arms depending on the order of allocation of each mode: pressure support 7 cm H2O + PEP 4 cm H2O then ATC or the opposite. The primary endpoint is the power of the work of breathing. The hypothesis is that the power of the work of breathing is greater in ATC than in the usual procedure, and hence this latter is a real ventilator support.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
20
Inclusion Criteria
  • age 18 years or more
  • intubated and mechanically ventilated for at least 24 consecutive hours
  • staying in the medical ICU at the Croix Rousse Hospital, Lyon, France
  • pressure support ventilation 10-15 cm H2O, total respiratory rate 25-35 breaths/min, expired tidal volume 6-8 ml/kg predicted body weight
  • meeting criteria for spontaneous breathing trial (able to answer simple questions, no ongoing intravenous sedation, norepinephrine ≤ 1 mg/H, dobutamine ≤ 20 mg/h, fraction of inspired oxygen (FIO2 ≤ 50%), PEP ≤ 5 cm H2O, respiratory rate ≤ 35 breaths/min, saturation in oxygen (SpO2) ≥88%)
  • under Dräger Evita XL ou V500 ICU ventilator
  • agreement to participate from the patient or next of kin
Read More
Exclusion Criteria
  • Chronic respiratory failure under long term home oxygen therapy and/or non invasive ventilation before ICU admission
  • Tracheotomy
  • nasogastric tube contra-indicated
  • thoracic tube in place
  • no agreement to participate
  • under justice protection
  • deprived of freedom
  • pregnant or breastfeeding
  • not affiliated to social insurance
  • involved into another study that may interfere with present study
Read More

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
ATC then pressure support 7 cm H2O PEP 4 cm H2OATC then pressure support 7 cm H2O PEP 4 cm H2Ospontaneous breathing through endotracheal tube with no ventilator support except for ATC
pressure support 7 cm H2O PEP 4 cm H2O then ATCPressure support 7 cm H2O PEP 4 cm H2O then ATCventilator is set to pressure support ventilation mode at set pressure 7 cm H2O above PEEP level of 4 cm H2O
Primary Outcome Measures
NameTimeMethod
the power of work of breathing30 minutes after onset the ventilator strategy

the work of breathing is measured from the area subtended by the esophageal pressure - lung volume relationship. The power of work of breathing is obtained by multiplying work of breathing by the respiratory frequency and expressed in Joules/min

Secondary Outcome Measures
NameTimeMethod
occlusion pressure at 100 ms30 minutes

measured from the airway pressure at the first 100 ms after airway occlusion

tidal volume30 minutes

integration of airflow over time during expiration

Respiratory rate30 minutes

the respiratory rate is measured from the airflow tracing

intrinsic PEP30 minutes

deflection in esophageal pressure up to the first zero flow

work of breathing per liter30 minutes

work of breathing normalized for 1 liter tidal volume

Distribution of pulmonary ventilation30 minutes

distribution of pulmonary ventilation will be measured by the Pulmovista system

Trial Locations

Locations (1)

Hôpital de la Croix Rousse

🇫🇷

Lyon, France

© Copyright 2025. All Rights Reserved by MedPath