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Not yet recruiting NCT07188038

The Impact of Low Versus High Positive End-expiratory Pressure on Diaphragm Function, Ventilation Efficiency, and Lung Mechanics

No phase Interventional Respiratory Failure ARDS (Acute Respiratory Distress Syndrome) Pneumonia Respiratory Insufficiency

For patients and families

In plain language

An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.

What is being studied
The protocol lists: Low positive end-expiratory pressure, Medium positive end-expiratory pressure, High positive end-expiratory pressure.
Who it may be relevant to
Registry conditions: Respiratory Failure, ARDS (Acute Respiratory Distress Syndrome), Pneumonia, Respiratory Insufficiency. Basic parameters: from 18 years · All.
What needs checking
Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
Where it takes place
Sweden
Next step
Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →

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Official title

The Impact of Low Versus High Positive End-Expiratory Pressure on Diaphragm Function, Ventilation Efficiency, and Lung Mechanics During Pressure Support Ventilation: A Randomized Interventional Crossover Study

Overview

The goal of this interventional study is to evaluate the effect of different positive end-expiratory pressures (PEEP) on lung and diaphragm function in patients mechanically ventilated with pressure support ventilation in the intensive care unit. The main questions aim to answer: Does higher PEEP level affect diaphragm contractions and ventilatory efficiency? Does higher PEEP level limit inspiratory efforts? Does higher PEEP level affect lung compliance? The participants will be subjected to three different PEEP levels during pressure support ventilation: Low PEEP (4 cmH2O), Medium PEEP (10 cmH2O), High PEEP (16 cmH2O). The lung and diaphragm function will be evaluated using high-resolution esophageal manometry, electrical activity of the diaphragm, external diaphragm ultrasound and spirometric ventilator data.

Interventions

  • Procedure Low positive end-expiratory pressure
    Low (4 cmH2O) positive end-expiratory pressure (PEEP) will be applied during pressure support ventilation. The PEEP level will be kept for 10 minutes prior to data acquisition.
  • Procedure Medium positive end-expiratory pressure
    Medium (10 cmH2O) positive end-expiratory pressure (PEEP) will be applied during pressure support ventilation. The PEEP level will be kept for 10 minutes prior to data acquisition.
  • Procedure High positive end-expiratory pressure
    High(16 cmH2O) positive end-expiratory pressure (PEEP) will be applied during pressure support ventilation. The PEEP level will be kept for 10 minutes prior to data acquisition.

Primary outcome measures

  • Inspiratory effort [Time frame: Measured during 5 uninterrupted breaths 10 minutes after application of interventional PEEP level]
  • Inspiratory drive [Time frame: Measured during 5 uninterrupted breaths 10 minutes after application of interventional PEEP level]
  • Effort-to-drive ratio [Time frame: Calculated from the measures collected 10 minutes after application of interventional PEEP level]
  • Neuromechanical efficiency [Time frame: Calculated from the measures collected during the occlusion manoeuvre performed 10-15 minutes after application of interventional PEEP level]
  • Thickening fraction of the diaphragm (TFdi) [Time frame: Measured 10 minutes after application of interventional PEEP level]
  • Transpulmonary driving pressure [Time frame: Measured during 5 breaths 10 minutes after application of interventional PEEP level]
  • Occlusion pressure [Time frame: The occlusion pressure will be measured during an occlusion manoeuvre performed 10-15 minutes after application of interventional PEEP level.]
Secondary outcome measures (5)
  • Airway driving pressure [Time frame: Measured during an inspiratory hold performed 10-15 minutes after application of interventional PEEP level]
  • Lung compliance [Time frame: Measured during an inspiratory hold performed 10 - 15 minutes after application of interventional PEEP level]
  • Thickening fraction of the expiratory abdominal muscles (TFabd) [Time frame: Measured 10 minutes after application of interventional PEEP level]
  • Oxygenation [Time frame: The blood gas will be collected 10 minutes after application of interventional PEEP level]
  • Respiratory system compliance [Time frame: Measured during an inspiratory hold manoeuvre performed 10-15 minutes after the application of interventional PEEP level.]

Eligibility criteria

Inclusion criteria

  • Mechanical ventilation with pressure support or mechanical ventilation with possibility to transition to pressure support
  • Oxygen requirement ≤ 50%
  • Pressure support ≤ 12 cmH2O
  • PEEP ≤ 12 cmH2O
  • Age ≥ 18 years
  • Adequate intravascular volume status

Exclusion criteria

  • Circulatory instability
  • Brain death diagnosis/brain death evaluation
  • Norepinephrine dose > 0.4 µg/kg/min
  • Muscle relaxation administered within 2 hours
  • Pregnancy
  • Contraindication to esophageal catheterization (e.g., esophageal varices)
  • Conditions with increased risk of pneumothorax (such as severe COPD (Chronic Obstructive Pulmonary Disease) or extensive emphysema)
  • Untreated pneumothorax
  • Symptomatic airway obstruction

Discontinuation criteria during ongoing study intervention:

  • Heart rate > 120 beats/min
  • Systolic blood pressure > 180 mmHg
  • Inspired oxygen fraction > 70%
  • Respiratory rate > 35/min
  • RASS (Richmond Agitation Sedation Scale) ≥ 2
  • Doubling of norepinephrine dose or increase of norepinephrine dose to > 0.5 µg/kg/min to maintain mean arterial pressure
  • Bradycardia < 45 beats/min

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation
Randomized
Model
Crossover
Masking
Single blind
Primary purpose
Supportive care

Study locations

Sweden · 2 centers
  • Central intensivvårdsavdelning, Sahlgrenska University Hospital — Gothenburg
  • Thorax intensivvårdsavdelning, Område 6, Sahlgrenska University Hospital, Västra Götalands — Gothenburg

Identifiers

NCT: NCT07188038 · 2025-01286-01

Primary sources (government registries)

View this study on ClinicalTrials.gov ↗