K. Freischlag2, M. S. Mulvihill1, P. M. Schroder1, B. Ezekian1, S. Knechtle1 1Duke University Medical Center,Surgery,Durham, NC, USA 2Duke University Medical Center,School Of Medicine,Durham, NC, USA
Introduction:
The optimal management of patients with combined lung and liver failure is uncertain. Simultaneous lung and liver transplantation (LLT) confers survival benefit over remaining on the waitlist for transplantation. In 2005, the lung allocation score (LAS) was introduced and significantly reduced waitlist and overall mortality in single organ lung transplants. The current system for simultaneous LLT generally matches a recipient with a donor based on his or her LAS. Oftentimes this results in a relatively low MELD score at transplantation compared to liver alone. However, the current impact of LAS on LLT is unknown. To ascertain whether the current lung allocation system has improved survivability in this cohort, we studied LLT before and after the introduction of LAS.
Methods:
The OPTN/UNOS STAR file was queried for adult recipients of simultaneous LLT. Demographic characteristics were subsequently generated and examined. Kaplan-Meier analysis with the log-rank test compared survival between groups. A hazard ratio was generated based on the presence of LAS alone.
Results:
A total of 64 recipients of LAS were identified as suitable for analysis. Of those, 10 underwent transplant prior to the introduction of LAS. Comparatively, those without a LAS score had a higher mean FEV1 (48.22 vs 29.56, p=0.012), higher mean creatinine at transplant (1.22 vs 0.73, p=0.001), higher percentage diagnosed with primary pulmonary hypertension (40% vs 0%, p=0.004), and an earlier mean transplant year (1999.4 vs 2011.17, p<0.001). Survival was significantly lower in the LLT cohort before the introduction of LAS compared to the cohort after LAS (Figure 1- 1-year: 50.0% vs 83.3%, 5-year: 40.0% vs 67.5%, 10-year: 20.0% vs 55.6%, p=0.0073). Presence of LAS was a predictor of decreased mortality (OR 0.051, 95%CI 0.006-0.436, p=0.007).
Conclusion:
LLT is a rare procedure and most national analyses have included patients before and after the introduction of the LAS. Our study shows that survival in combined lung-liver transplantation after the introduction of the lung allocation score was significantly increased and presence of LAS was a predictor of decreased mortality. While many factors contributed to the changes in mortality, the cohorts before and after the introduction of LAS are significantly different and should be treated as such when conducting future studies in simultaneous thoracic and abdominal organ allocation.
