Impact of EIT-based regional ventilation distribution on outcomes in different types of critical illness: a...

Electrical impedance tomography (EIT) is a non-invasive bedside tool for real-time regional ventilation data, but its correlation with outcomes in different critical illnesses remains unclear.

This retrospective study included 108 ICU patients (liver disease, n = 48; respiratory failure, n = 36; gastrointestinal bleeding, n = 24) who underwent EIT monitoring between December 2023 and March 2025. EIT measured tidal volume percentage in four regions of interest (ROIs), with 28-day mortality as the primary outcome. Multivariate logistic regression adjusted for key confounders was used for analysis.

Ventilation distribution patterns differed significantly among the three disease groups. The liver disease group showed predominant ventilation in ROI 1-2 (anterior regions), with a mean dorsal-to-ventral ratio (DVR) of 0.41 ± 0.18. The respiratory failure group exhibited more homogeneous distribution with a DVR of 0.76 ± 0.34. Patients with higher ventilation heterogeneity (coefficient of variation > 40%) had significantly higher 28-day mortality (29.5% vs 16.7%, p = 0.022), longer duration of mechanical ventilation (8.7 vs 5.4 days, p = 0.012), and fewer ventilator-free days (14.3 vs 19.6 days, p = 0.009). Multivariate analysis identified DVR < 0.4 (OR 2.84, 95% CI 1.46-5.53, p = 0.002) and ventilation heterogeneity (OR 2.31, 95% CI 1.18-4.52, p = 0.014) as independent predictors of 28-day mortality after adjusting for disease severity, age, and mechanical ventilation parameters.

Regional ventilation patterns vary by underlying disease. Greater heterogeneity and lower DVR independently correlate with worse outcomes. EIT-derived parameters may be prognostic indicators and therapeutic targets for optimizing ventilation in critical illness.