Improved survival in simultaneous lung-liver recipients and candidates in the modern era of lung allocation

Progress in Combined Liver-lung Transplantation at a Single Center

Combined liver-lung transplantation is an uncommon, although vital, procedure for patients with simultaneous end-stage lung and liver disease. The utility of lung-liver transplant has been questioned because of initial poor survival outcomes, particularly when compared with liver-alone transplant recipients.

Methods

A single-center, retrospective review of the medical records of 19 adult lung-liver transplant recipients was conducted, comparing early recipients (2009-2014) with a recent cohort (2015-2021). Patients were also compared with the center's single lung or liver transplant recipients.

Results

Recent lung-liver recipients were older (P = 0.004), had a higher body mass index (P = 0.03), and were less likely to have ascites (P = 0.02), reflecting changes in the etiologies of lung and liver disease. Liver cold ischemia time was longer in the modern cohort (P = 0.004), and patients had a longer posttransplant length of hospitalization (P = 0.048). Overall survival was not statistically different between the 2 eras studied (P = 0.61), although 1-y survival was higher in the more recent group (90.9% versus 62.5%). Overall survival after lung-liver transplant was equivalent to lung-alone recipients and was significantly lower than liver-alone recipients (5-y survival: 52%, 51%, and 75%, respectively). Lung-liver recipient mortality was primarily driven by deaths within 6 mo of transplant due to infection and sepsis. Graft failure was not significantly different (liver: P = 0.06; lung: P = 0.74).

Conclusions

The severity of illness in lung-liver recipients combined with the infrequency of the procedure supports its continued use. However, particular attention should be paid to patient selection, immunosuppression, and prophylaxis against infection to ensure proper utilization of scarce donor organs.

Combined Heart-Lung-Liver Transplantation for Patients With Cystic Fibrosis: The Australian Experience

BACKGROUND

Combined multivisceral transplantation has emerged as a therapeutic option for a select patient cohort; however, clinical decision-making remains complex and controversial. The aim of this study was to examine patient characteristics, operative complications, and long-term outcomes of all patients who have undergone combined heart-lung-liver transplantation (HLLTx) in Australia.

METHODS

In this study, we performed a retrospective analysis of all adult patients who have undergone combined HLLTx in Australia to date. Recipient clinical characteristics, waitlist, and transplant outcomes are described.

RESULTS

Eight adult patients have received HLLTx at a single Australian transplant center. Recipients of HLLTx have typically been young (median age, 30.1 years; range, 24-37), underweight (median body mass index, 19.8 kg/m²; range, 16.2-30.4) patients with cystic fibrosis (n = 8, 100%) with severe airflow obstruction (median forced expiratory volume in the first second of expiration, 24% predicted; range, 17%-48%) accompanied by liver cirrhosis confirmed on histopathology (n = 8, 100%). Despite relative preservation of synthetic function and low model for end-stage liver disease scores (median, 8; range, 6-17), all recipients had complications of portal hypertension prior to transplantation, with many patients having suffered life-threatening variceal hemorrhage. In this cohort, HLLTx was associated with overall posttransplant survival of 87.5% at 30 days, 71.4% at 1 year, and 42.9% at 5 years. Listing for combined HLLTx was associated with prolonged waitlist times relative to bilateral sequential single-lung transplantation (median 556 vs 56 days, respectively), however waitlist mortality and/or delisting was comparable between groups.

CONCLUSIONS

Taken together, these findings highlight the opportunities and challenges facing combined (heart-) lung and liver transplantation in patients with multiorgan failure.

Selection Criteria for Lung Transplantation: Controversies and New Developments

Lung transplantation is an accepted therapeutic option for end-stage lung diseases. The imbalance between limited availability and vast need of donor organs necessitates careful selection of recipient candidates, ensuring the best possible utilization of the scarce resource of organs. Nonetheless, possible lung transplant candidates who could experience a meaningful improvement in survival and quality of life should not be excluded solely based on the complexity of their case. In this review, controversial issues or difficult limitations for lung transplantation, and new developments in recipient selection criteria, are discussed, which may help broaden recipient eligibility for lung transplantation without compromising long-term outcomes.

A review of liver dysfunction in the lung transplant patient

Liver dysfunction is an increasingly common finding in patients evaluated for lung transplantation. New or worsening dysfunction in the perioperative period, defined by presence of clinical ascites/encephalopathy, high model for end-stage liver disease (MELD) score, and/or independent diagnostic criteria, is associated with high short- and long-term mortality. Therefore, a thorough liver function assessment is necessary prior to listing for lung transplant. Unfortunately, identification and intraoperative monitoring remain the only options for prevention of disease progression with isolated lung transplantation. Combined lung and liver transplantation may provide an option for definitive long-term management in selecting patients with known liver disease at high risk for postoperative progression. However, experience with the combined operation is extremely limited and indications for combined lung and liver transplant remain unclear. Herein, we present a comprehensive literature review of patients with liver dysfunction undergoing lung transplantation with and without concurrent liver transplant in an effort to illuminate the risks, benefits, and clinical judgement surrounding decision to pursue combined lung-liver transplantation (CLLT). We also argue description of liver function is currently a weakness of the current lung allocation scoring system. Additional algorithms incorporating liver function may aid in risk stratification and decision to pursue combined transplantation.

A Propensity-matched Survival Analysis: Do Simultaneous Liver-lung Transplant Recipients Need a Liver?

BACKGROUND

There is debate whether simultaneous lung-liver transplant (LLT) long-term outcomes warrant allocation of 2 organs to a single recipient. We hypothesized that LLT recipients would have improved posttransplant survival compared with matched single-organ lung recipients with an equivalent degree of liver dysfunction.

METHODS

The Organ Procurement and Transplant Network/United Network for Organ Sharing STAR file was queried for adult candidates for LLT and isolated lung transplantation from 2006 to 2016. Waitlist mortality and transplant odds were calculated for all candidates. Donor and recipient demographic characteristics were compiled and compared. The LLT recipients were matched 1:2 with a nearest neighbor method to single-organ lung recipients. Kaplan-Meier methods with log-rank test compared long-term survival between groups. Univariate regression was used to calculate the association of LLT and mortality within 6 months of transplant. A proportional hazards model was used to calculate risk-adjusted mortality after 6 months posttransplantation.

RESULTS

Thirty-eight LLT patients were matched to 75 single-organ lung recipients. After matching, no differences in baseline demographics or liver function were observed between cohorts. Length of stay was significantly longer in LLT recipients compared to isolated lung recipients (45.89 days vs 22.44 days, P < 0.001). There was no significant difference in survival probability between LLT and isolated lung transplant (1 y, 89.5% vs 86.7%; 5 y, 67.0% vs 64.6%; P = 0.20).

CONCLUSIONS

After matching for patient characteristics and level of liver dysfunction, survival in simultaneous LLT was comparable to isolated lung transplantation. Although this population is unique, the clinical picture prompting liver transplant is not clear. National guidelines to better elucidate patient selection are needed.

Lung transplantation: a review of the optimal strategies for referral and patient selection

One of the great challenges of lung transplantation is to bridge the dichotomy between supply and demand of donor organs so that the maximum number of potential recipients achieve a meaningful benefit in improvements in survival and quality of life. To achieve this laudable goal is predicated on choosing candidates who are sufficiently unwell, in fact possessing a terminal respiratory illness, but otherwise fit and able to undergo major surgery and a prolonged recuperation and rehabilitation stage combined with ongoing adherence to complex medical therapies. The choice of potential candidate and the timing of that referral is at times perhaps more art than science, but there are a number of solid guidelines for specific illnesses to assist the interested clinician. In this regard, the relationship between the referring clinician and the lung transplant unit is a critical one. It is an ongoing and dynamic process of education and two way communication, which is a marker of the professionalism of a highly performing unit. Lung transplantation is ultimately a team effort where the recipient is the key player. That principle has been enshrined in the three consensus position statements regarding selection criteria for lung and heart-lung transplantation promulgated by the International Society for Heart and Lung Transplantation over the last two decades. During this period, the number of indications for lung transplantation have broadened and the number of contraindications reduced. Risk management is paramount in the pre- and perioperative period to effect early successful outcomes. While it is not the province of this review to reiterate the detailed listing of those factors, an overview position will be developed that describes the rationale and evidence for selected criteria where that exists. Importantly, the authors will attempt to provide an historical and experiential basis for making these important and life-determining decisions.

The reviews of this paper are available via the supplementary material section.