Real-time lung weight measurement during clinical ex vivo lung perfusion.

ABSTRACT

BACKGROUND: Real-time lung weight (LW) measurement is a simple and non-invasive technique for detecting extravascular lung water during ex vivo lung perfusion (EVLP). We investigated the feasibility of real-time LW measurement in clinical EVLP as a predictor of transplant suitability and post-transplant outcomes. METHODS: In our clinical acellular EVLP protocol, real-time LW was measured in 117 EVLP cases from June 2019 to June 2022. The estimated LW gain at each timepoint was calculated using a scale placed under the organ chamber. The lungs were classified into four categories based on LW adjusted for height and compared between suitable and unsuitable cases. The relationship between estimated LW gain and primary graft dysfunction was also investigated. RESULTS: The estimated LW gain during the EVLP significantly correlated with the LW gain (post EVLP LW - pre EVLP LW) measured on the back table (R2=0.61, P<0.01). In the adjusted LW categories 2-4, the estimated LW gain at 0-1 h after EVLP was significantly higher in unsuitable cases than in suitable cases. The area under the curve for the estimated LW gain was ≥0.80. Primary graft dysfunction grade 0-1 had a significantly lower estimated LW gain at 60 min than grades 2-3 (-43 vs. 1 g, P<0.01). CONCLUSIONS: Real-time lung measurements can predict transplant suitability and post-transplant outcomes by the early detection of extravascular lung water during the initial 1 h of EVLP.