Acute Respiratory Failure, Ventilator Weaning Assessment
Conditions
Keywords
acute respiratory failure, Respiratory drive, Electrical Impedance Tomography (EIT)
Brief summary
Accurate prediction of readiness to liberate patients from mechanical ventilation remains challenging. Conventional indices such as the rapid shallow breathing index (RSBI) and maximal inspiratory pressure (MIP) often miss early signs of injurious breathing patterns or regional ventilation asynchrony that can lead to extubation failure. Electrical impedance tomography (EIT) provides continuous, non-invasive imaging of regional lung ventilation. We developed a novel EIT-derived Flow Index (FI) which integrates the magnitude of inspiratory effort with the temporal synchrony of lung filling. This prospective, multicenter observational study aimed to (1) validate the predictive value of FI during spontaneous breathing trials (SBT) compared with conventional weaning indices, and (2) compare the predictive ability of EFI with traditional weaning indices(RSBI,MIP,P0.1).
Detailed description
This multicenter observational study was conducted in three tertiary ICUs in China. Adult patients (≥18 years) receiving invasive mechanical ventilation for ≥48 hours and meeting readiness criteria underwent a standardized 30-minute pressure support SBT (PS 8 cmH₂O, PEEP 5 cmH₂O, FiO₂ ≤0.5) with continuous EIT monitoring. EFI was calculated breath by breath from the global impedance-time signal. Conventional weaning indices (RSBI, MIP, P0.1) and physiological variables were recorded. Primary endpoint: SBT success (completion of 30-minute SBT without predefined failure criteria). Key secondary endpoint: reintubation within 48 hours after extubation. Other secondary endpoints: ventilator-free days at day 7 (VFD-7), ICU mortality. Predictive performance was assessed using ROC analysis. The EFI cutoff value was derived from the primary endpoint analysis and carried forward for post-extubation risk stratification.
Interventions
DEVICEelectrical impedance tomography
Respiratory drive assessed by flow index measured by electrical impedance tomography.
Sponsors
Ruijin Hospital
Fujian Provincial Hospital
Peking Union Medical College Hospital
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 90 Years
Healthy volunteers
No
Inclusion criteria
* Age ≥18 years * Acute respiratory failure requiring intubation and mechanical ventilation ≥48 hours * Hemodynamic stability (no escalation of vasoactive agents) * Oxygenation: FiO₂ ≤0.5, PEEP ≤8 cmH₂O * Meeting standard ICU criteria for SBT readiness
Exclusion criteria
* Neuromuscular diseases impairing spontaneous breathing * High cervical spinal cord injury * Deep sedation (RASS ≤-3) * Inadequate EIT signal quality * Contraindications to EIT * Pregnancy * Expected survival \<24 h
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Spontaneous Breathing Trial (SBT) Success Rate | Within 30 minutes of Spontaneous Breathing Trial (SBT) | Proportion of patients who complete the 30-minute Spontaneous Breathing Trial (SBT) without signs of respiratory distress, hypoxemia, or hemodynamic instability. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Reintubation Rate within 48 hours | Within 48 hours after extubation. | Proportion of patients requiring reintubation within 48 hours following successful extubation. |
| Ventilator-Free Days by Day 7 | Within 7 days after extubation. | Number of days free from mechanical ventilation within 7 days after extubation. |
| ICU Mortality | during the ICU stay or within 24 hours following transfer out of the ICU | Mortality rate of patients during their ICU stay in this study. |
| Reintubation rate within 48 hours after extubation | within the 48 hours after extubation | Proportion of patients who successfully completed the spontaneous breathing trial (SBT) and underwent planned extubation who required reintubation within 48 hours after extubation. |
| Ventilator-Free Days at Day 7 (VFD-7) | Within 7 days after extubation | Number of days alive and free from invasive mechanical ventilation within 7 days after extubation. Days after reintubation are not counted as ventilator-free days. |
Countries
China
Contacts
STUDY_CHAIRHongping Qu
Department of Critical Care Medicine，Ruijin Hospital，Shanghai Jiao Tong University School of Medicine
STUDY_DIRECTORJialin Liu
Department of Critical Care Medicine，Ruijin Hospital，Shanghai Jiao Tong University School of Medicine
PRINCIPAL_INVESTIGATORrui zhang
Department of Critical Care Medicine，Ruijin Hospital，Shanghai Jiao Tong University School of Medicine
Outcome results
None listed