Electrical Impedance Tomography Monitoring During Extubation in Critically Ill Children

Abstract

Highlights: What are the main findings? Significant changes observed in key EIT parameters, including ΔEELI, tidal impedance, and global inhomogeneity, were consistently observed across the pre- and post-extubation time points in critically ill children. No extubation failure occurred in this study. Most respiratory and EIT parameters were similar in patients with abnormal compared to normal chest X-ray findings, with differences observed in TID and ODCL immediately after extubation. What are the implications of the main findings? EIT can detect dynamic changes in lung volume and ventilation distribution around extubation in pediatric patients; however, its ability to identify extubation failure could not be evaluated in the absence of failed extubation events. The high rate of prophylactic HFNC/NIV use may influence extubation physiology and should be considered when interpreting EIT trends or designing future pediatric extubation studies. Background: Extubation failure increases morbidity and mortality. Non-invasive ventilation (NIV), including high-flow nasal cannula (HFNC), can reduce reintubation rates. Current practice often involves prophylactic use of NIV post-extubation. Electrical Impedance Tomography (EIT) provides real-time monitoring of pulmonary distribution and ventilation. Recent adult studies suggest that EIT has potential in extubation failure prediction, but evidence in children is limited. Our objectives were to evaluate peri-extubation regional lung volume/distribution and to explore EIT-derived physiological changes and on post-extubation respiratory support patterns in critically ill children. Methods: A prospective observational study included intubated patients aged 1 month to 18 years in the PICU who were intubated for over 24 h. Vital signs and chest EIT were recorded pre-extubation (H0), immediately post-extubation (H1), at 30 min (H2), and at 4 h (H3). Patients were categorized by chest X-ray findings into abnormal or normal groups. Results: Among 209 ventilated patients, 54 were included. End-expiratory lung impedance (∆EELI), tidal impedance (TID), and the global inhomogeneity index (GI) demonstrated significant changes across predefined peri-extubation time points. Thirty-eight (70.4%) patients received HFNC or NIV immediately after extubation. No extubation failures occurred, precluding evaluation of extubation failure predictors. In the subgroup analyzed based on chest X-ray findings, differences in TID and ODCL were observed between patients with normal and abnormal chest X-rays immediately after extubation. Conclusions: The ∆EELI, TID, and GI demonstrated significant changes across predefined peri-extubation time points. In the absence of extubation failure events, the ability of EIT monitoring to evaluate extubation failure could not be assessed. The frequent use of prophylactic NIV support after extubation may have influenced post-extubation physiology.