Lowering PEEP: Weaning From High PEEP Setting

Effects of Positive End Expiratory Pressure (PEEP) Decrease in Patient With Acute Respiratory Distress Syndrome (ARDS) Ventilated According to High PEEP Strategy (ExPress Trial).

The perfusion of the deeply different areas coexisting in ARDS lung generates two type of venus-admixure : true shunt and shunt effect. Briefly, true shunt and shunt effect are related to non-aerated and poorly-ventilated lung areas perfusion respectively. Practically, it is not possible to quantify the true shunt and the shunt-effect directly, but we can measure the "total-shunt", i.e. the sum of two kind of venus-admixured. As it is known from classical physiology, the effects of FiO2 variations on PaO2 are deeply different depending on the type of venous admixures. In the case of a patient with virtually only true shunt, any FiO2 variation will not modify the PaO2. On the other hand, in a patient with virtually only a shunt effect, increasing the FiO2 the PaO2 will progressively increase. Indeed, ventilating a patient presenting only a shunt effect (without true shunt) with pure oxygen will generate a "normal" P/F ratio. In patients ventilated with high PEEP levels it is difficult to predict based on the P/F ratio the relative amount of true shunt and shunt effect. However, patients presenting a significant shunt effect when ventilated with higher PEEP level would likely have "unstable" poorly aerated lung areas that need PEEP to remain opened. In those patients, a PEEP-weaning protocol based on the P/F ratio could induce significant alveolar de-recruitment and clinical deterioration. On the contrary, patients with less shunt effect would be likely less prone to alveolar de-recruitment and would benefice from PEEP decrease.

Study Overview

• Status: Completed
• Conditions: Mechanical Ventilation Complication
• Intervention / Treatment: Other: decrease the positive end expiratory pressure (PEEP); Other: mechanical features assessment; Other: shunt assessment

Detailed Description

the investigators set up a study to test the hypothesis that patients presenting a significant shunt effect when ventilated with higher PEEP levels could be prone to significant alveolar de-recruitment at the PEEP weaning attempt. To do so, the investigator has to measure the total shunt at higher PEEP level in patients ready to be weaned from the PEEP (according to the Mercat protocol), at three FiO2 levels (i.e. 0,3, 0,6 and 1). The shunt effect is quantified as the difference in total shunt between FiO2 0,3 and .The hypothesis of this study is that the shunt effect could predict alveolar de-recruitment when weaning PEEP.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Italy
  • Bari, Italy, 70124
    • Azienda Ospedaliero Universitaria Policlinico

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age major than 18
• 1-2 days since the beginning of mechanical ventilation
• Moderate or severe ARDS

Exclusion Criteria:

• Patients with a story of chronic obstructive pulmonary disease (COPD)
• Patients with asthma
• Patients with neurological disease
• Patients with heart disease
• Patients with cardiopulmonary.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: NON_RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: SINGLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
OTHER: High positive end-expiratory pressure Ventilation; patient ventilated fixing high level of positive end expiratory pressure	Other: decrease the positive end expiratory pressure (PEEP); decrease the PEEP going from high (according to ExPress Trial) to low level; Other: mechanical features assessment; evaluation of the mechanical features of respiratory system; Other: shunt assessment; evaluation of the pulmonary shunt during two different ventilation setting
OTHER: Low positive end-expiratory pressure Ventilation; patient ventilated fixing low level of positive end expiratory pressure	Other: mechanical features assessment; evaluation of the mechanical features of respiratory system; Other: shunt assessment; evaluation of the pulmonary shunt during two different ventilation setting

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
de-recruitment	the shunt effect cold predict the lung de-recruitment volume	decreasing PEEP from high to low levelthrough study completion, an average of 2 years

Collaborators and Investigators

• Sponsor: University of Bari

Study record dates

Study Major Dates

• Study Start (ACTUAL): September 21, 2019
• Primary Completion (ACTUAL): June 21, 2021
• Study Completion (ACTUAL): January 1, 2022

Study Registration Dates

• First Submitted: June 4, 2020
• First Submitted That Met QC Criteria: June 10, 2020
• First Posted (ACTUAL): June 12, 2020

Study Record Updates

• Last Update Posted (ACTUAL): January 21, 2022
• Last Update Submitted That Met QC Criteria: January 20, 2022
• Last Verified: January 1, 2022

More Information

Terms related to this study

• Other Study ID Numbers: 6011

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No