Delta Pocc During Spontaneous Breathing Trial to Predict Extubation Failure in Mechanically Ventilated Adults (DELTA-EXT)

This prospective observational single-center study will evaluate whether dynamic respiratory stress estimated by delta airway occlusion pressure deflection (Delta Pocc) during a standardized spontaneous breathing trial can predict extubation failure in mechanically ventilated adult intensive care unit patients. Liberation from invasive mechanical ventilation is a critical step in ICU care. Although spontaneous breathing trials are routinely used to assess readiness for extubation, some patients may successfully complete the trial despite experiencing excessive respiratory effort and physiological stress, which may increase the risk of extubation failure. This study will include adult ICU patients who have received invasive mechanical ventilation for at least 24 hours and are considered ready for a spontaneous breathing trial according to the treating clinical team. During the trial, respiratory, ventilatory, and hemodynamic variables will be recorded at predefined time points, including measurements of Delta Pocc as a non-invasive estimate of inspiratory effort and dynamic stress. The primary outcome is extubation failure within 48 hours after extubation, defined as reintubation and/or the need for rescue non-invasive respiratory support due to post-extubation respiratory deterioration. The study aims to determine whether this physiological measurement may improve risk stratification during weaning and complement conventional clinical decision-making.

Inclusion Criteria: * Age 18 years or older * Invasive mechanical ventilation for at least 24 hours * Clinical indication for spontaneous breathing trial according to the treating clinical team * Hemodynamic and clinical stability * Technical feasibility for respiratory physiological measurements, including expiratory occlusion maneuver Exclusion Criteria: * Significant hemodynamic instability * Severe uncontrolled hypoxemia * Major cardiac arrhythmias * Agitation or patient-ventilator asynchrony preventing reliable measurements * Significant air leak interfering with respiratory measurements * Technical inability to perform expiratory occlusion maneuver * Limitation of life-sustaining treatment * Incomplete primary outcome follow-up