High Lung Allocation Scores and Lung Transplantation: Is There a Ceiling?

Spirometry testing for extracorporeal membrane oxygenation (ECMO) bridge to transplant patients

PURPOSE

ECMO can provide a bridge to transplantation and improve survival for patients with advanced lung disease. Although pulmonary function testing (PFT) is an important component of the lung allocation score (LAS), it is not always feasible on patients requiring ECMO. While generally safe, PFT testing has contraindications and is not recommended in unstable patients. Currently there are no recommendations regarding the performance of spirometry in ECMO patients.

STUDY DESIGN

and Methods: We reviewed data on five patients with advanced lung disease requiring ECMO-bridge to transplant. After careful consideration of the theoretical physiologic risks associated with forced expiratory maneuvers, bedside spirometry was performed in order to update the patients' LAS.

RESULTS

All patients successfully completed three forced expiratory maneuvers in the seated position with a bedside spirometer. Vital signs and ECMO flow were stable during testing and without complication. In 2 patients who had both a LAS pre and post spirometry, the LAS increased by 3-5 points.

CONCLUSION

Spirometry results are pivotal to organ allocation under current organ sharing protocols. This case series demonstrates that bedside spirometry testing may be performed safely in patients on ECMO awaiting lung transplantation without appreciable side effects, leading to a more accurate LAS score.

Evolution of Recipient Characteristics Over 3 Decades and Impact on Survival After Lung Transplantation

BACKGROUND

Lung transplantation (LTx) is a definitive treatment for end-stage lung disease. Herein, we reviewed our center experience over three decades to examine the evolution of recipient characteristics and contemporary predictors of survival for LTx.

METHODS

We retrospectively reviewed the data of LTx procedures performed at our institution from 1/1990 to 1/2019 (n=1819). The cohort is divided into three eras; I: 1990-1998 (n=152), II: 1999-2008 (n=521), III: 2009-2018 (n=1146). Uni- and multivariate analyses of survival in era III were performed.

RESULTS

Pulmonary fibrosis has become the leading indication for LTx (13% in Era I, 57% in Era III). Median recipient age increased (Era I: 46 years - Era III: 61 years) as well as intraoperative mechanical circulatory support (Era I: 0% - Era III: 6%). Higher lung allocation score (LAS) was associated with primary graft dysfunction (PGD) (p<0.0001), postoperative ECMO (p<0.0001), and in-hospital mortality (p=0.002). In Era III, hypoalbuminemia, thrombocytopenia, and high PGD grade were multivariate predictors of early mortality. The 5-year survival in Era II (55%) and III (55%) were superior to Era I (40%, p<0.001). Risk factors for late mortality in era III included recipient age, chronic allograft dysfunction, renal dysfunction, high MELD score, and single LTx.

CONCLUSIONS

In this longitudinal single-center study, recipient characteristics have evolved to include sicker patients with greater complexity of procedures and risk for postoperative complications but without significant impact on hospital mortality or long-term survival. With advancing surgical techniques and perioperative management, there is room for further progress in the field.Supplemental Visual Abstract; http://links.lww.com/TP/C191.