Non-Invasive Respiratory Monitoring to Predict Successful Separation From Mechanical Ventilation Following Upper Abdominal Surgery

The VALUE Study is a two-phase, prospective clinical trial conducted at King Chulalongkorn Memorial Hospital (KCMH). The study evaluates the prevalence of mechanical ventilation (MV) separation failure in post-open upper abdominal surgery patients and investigates whether non-invasive bedside respiratory monitoring tools can rapidly predict extubation failure. The protocol focuses on Electrical Impedance Tomography (EIT) metrics-specifically regional ventilation distribution and the absolute ventral-to-dorsal difference-alongside ventilator-derived measures of respiratory drive. It also tracks physiological responses and clinical outcomes, including dyspnea using the Intensive Care Respiratory Distress Observation Scale (IC-RDOS) and the ROX index, across standard post-extubation oxygen delivery methods (nasal cannula vs. High-Flow Nasal Cannula \[HFNC\]).

Inclusion criteria * Age of ≥ 18 years * Post elective open upper abdominal surgery with mechanical ventilation * Get readiness for mechanical ventilation weaning with pressure support 5-8 cmH2O and PEEP 5-8 cmH2O set by clinical team and prompt extubation assessed by clinical team Exclusion criteria * Previous tracheostomy * Contraindication to EIT placement: pacemaker/defibrillator implantation, burns at the area of EIT placement * Patient with end-of-life plan * Emergency operation