Use of a novel donor lung scoring system as a tool for increasing lung recovery for transplantation

Abstract

There is a critical shortage of donor lungs for transplantation. We previously developed a parsimonious, highly discriminatory nine-variable Lung Donor (LUNDON) acceptability score. We assess the utility of this score as a tool to improve lung recovery rates for transplantation. We examined all brain-dead donors between 2014-2020 from three US organ procurement organizations and validated the score's predictive performance. We examined the trajectory of donors with low (<40) and high (>60) initial LUNDON scores, their corresponding lung recovery rates, factors contributing to score improvement using multivariable regression models, and one-year post-transplant recipient survival. Overall lung recovery was 32.4% (1410/4351). Validation of the LUNDON score in our cohort revealed a C statistic of 0.904 but required intercept calibration. Low initial LUNDON donors that improved to a high final score had an increase in lung recovery rate from 29.3% (1100/3765) to 86.8% (441/508), associated with lower BMI, management in specialized donor care facilities (SDCF), and more bronchoscopies. Donors with high initial and final LUNDON scores had lung recovery rate of 85.2% (98/115), associated with shorter lengths of stay. One-year survival was similar between recipients of low-to-high versus high-to-high LUNDON score donors (0.89 vs 0.84, p=0.2). The LUNDON score performs well as a predictor of lung recovery in a contemporary cohort but may require OPO-specific calibration. SDCF use, more bronchoscopies, and expediting time from brain death to organ procurement may improve lung utilization. The LUNDON score can be used to guide donor management to expand the donor pool.