EIT Outperforms Quantitative CT in Stratifying ARDS Severity After Lung Transplantation: A Retrospective Study.

Area of Science:

• Pulmonary Medicine
• Critical Care Medicine
• Radiology

Background:

• Acute Respiratory Distress Syndrome (ARDS) in lung transplant recipients presents complex pathophysiologic alterations.
• Respiratory mechanics, gas exchange, CT, and EIT are key for evaluating lung function.

Purpose of the Study:

• To explore multimodal assessment of ventilation/perfusion (V/Q) function in post-lung transplantation ARDS.
• To integrate dynamic imaging and regional lung analysis into a multimodal system.

Main Methods:

• Retrospective enrollment of lung transplant recipients meeting ARDS Berlin criteria and P/F ratio ≤ 300 mmHg.
• Collected respiratory mechanics, gas exchange, EIT, and CT data; stratified patients into low (P/F < 200) and high (200 ≤ P/F ≤ 300) P/F groups.
• Utilized EIT for V/Q parameters (e.g., EIT-Dead Space, EIT-Shunt) and CT for quantitative lung analysis.

Main Results:

• The low P/F group showed significantly higher ventilation ratio (VR), regional ventilation delay index (RVDI), and EIT-Dead Space, with lower EIT-V/Q matching compared to the high P/F group.
• EIT-Dead Space correlated positively with ventilator-measured dead space fraction.
• No significant differences in CT-derived lung volumes or lesion volumes were observed between the groups.

Conclusions:

• Lung transplant recipients with ARDS and lower P/F ratios exhibit increased ventilation delay and dead space, as indicated by EIT.
• Quantitative CT metrics for lung lesions did not differ significantly between low and high P/F groups.
• EIT combined with CT offers a multimodal approach for assessing V/Q function in this patient population.