A CLUE for Better Assessment of Donor Lungs: Novel Technique in Clinical Ex-vivo Lung Perfusion.
Background Direct lung ultrasound evaluation (CLUE) technique was proven to be an accurate method for monitoring extravascular lung water in donor lungs during ex-vivo lung perfusion (EVLP) in an experimental model. The aim of this study was to examine the application of CLUE in clinical setting. Methods Lungs were evaluated using acellular EVLP protocol. Ultrasound images were obtained directly from the lung surface. Images were graded according to the percentage of B-lines seen on ultrasound. CLUE scores were calculated at the beginning and end of EVLP for the whole lung, each side, and lobe based on the number of images in each grade and the total number of images taken. Results Out of the 45 lungs, 22 were deemed suitable resulting in 13 lung transplants (LTx) with no hospital mortality. Primary graft dysfunction occurred in only one recipient (PGD3 no PGD2). Significant differences were found between suitable and non-suitable lungs in CLUE scores (1.03 vs 1.85, p<0.001) unlike PaO2/FiO2 ratio. CLUE had the highest area under the receiver-operating characteristic curve (0.98) when compared to other evaluation parameters. The initial CLUE score of standard donor lungs was significantly better than marginal lungs. Final CLUE score in proned lungs showed improvement when compared to initial CLUE score, especially in the upper lobes. Conclusion CLUE technique shows the highest accuracy in evaluating donor lungs for LTx suitability compared to other parameters used in EVLP. CLUE can optimize the outcomes of LTx by guiding the decision making through the whole process of clinical EVLP.