Donor total lung capacity predicts recipient total lung capacity after size-reduced lung transplantation

Background: Size-reduced lung transplantation has only recently undergone widespread use, especially in highly urgent cases. However, it is still not considered standard procedure at most centers. It has the potential to alleviate the donor organ shortage by allowing the use of oversized grafts for small and pediatric recipients. Limited data exist on pre-operative parameters predicting functional outcome after lung transplantation in general, especially after size-reduced lung transplantation. Methods: All 98 patients undergoing primary lung transplantation during a 2-year period, including 27 size-reduced lung transplantations, were analyzed retrospectively. Pre-operative functional parameters were-after correction of estimated values according to the amount of size reduction-correlated with post-operative functional assessment. Actual and predicted total lung capacity (TLC) of transplant recipients and predicted TLC of donors was compared with the best post-operative TLC achieved within 12 months after transplantation. Results: Size-reduced lung transplantation was performed in 27 cases. Downsizing was achieved by lobar transplantation (n = 9), split-lung transplantation (n = 2) or peripheral segmental resection (n = 16). There was a statistically highly significant (p < 0.01) correlation between donor TLC and best recipient TLC achieved after transplantation (Pearson's correlation coefficient = 0.675). No statistically significant correlation was seen between pre-operative recipient actual TLC and best post-operative TLC (p = 0.87; Pearson's correlation coefficient = 0.415). In standard lung transplant recipients post-operative TLC was correlated with both donor predicted TLC (P < 0.01; Pearson's correlation coefficient 0.509) and actual pre-operative recipient TLC (P < 0.01; Pearson's correlation coefficient 0.667). Conclusions: Post-operative recipient TLC in size-reduced lung transplantation can be predicted by donor TLC rather than pre-operative recipient TLC.