An international comparison of deceased donor kidney utilization: What can the United States and the United Kingdom learn from each other?

In transplant, meaningful international comparisons in organ utilization are needed. This collaborative study between the United Kingdom (UK) and the United States (US) aimed to develop a kidney utilization metric allowing for legitimate intercountry comparisons. Data from the UK and US transplant registries, including all deceased donor kidneys recovered from 2006 to 2017, were analyzed. To identify a potentially comparable kidney utilization rate (UR), several denominators were assessed. We discovered that the proportion of transplanted kidneys from elderly donors in the UK (10.7%) was 18 times greater than that in the US (0.6%). Conversely, en bloc pediatric kidney transplant was more common in the US. Donation after circulatory death utilization has risen in both countries but is twice as prevalent in the UK (39% of transplants) vs the US (20%). In addition, US and UK URs are not directly comparable due to fundamental system differences. However, using a suite of URs revealed practice areas likely to yield the most benefit if improved, such as efforts to increase kidney offer acceptance in the US and to reduce postacceptance discard in the UK. Methods used in this study, including novel intracountry risk-adjusted UR trend logistic regression analyses, can be translated to other international transplant registries in pursuit of further global learning opportunities.

Patient outcomes from time of listing for lung transplantation in the UK: are there disease-specific differences?

BACKGROUND: The demand for lung transplantation vastly exceeds the availability of donor organs. This translates into long waiting times and high waiting list mortality. We set out to examine factors influencing patient outcomes from the time of listing for lung transplantation in the UK, examining for differences by patient characteristics, lung disease category and transplant centre. METHODS: Data were obtained from the UK Transplant Registry held by NHS Blood and Transplant for adult lung-only registrations between 1January 2004 and 31 March 2014. Pretransplant and post-transplant outcomes were evaluated against lung disease category, blood group and height. RESULTS: Of the 2213 patient registrations, COPD comprised 28.4%, pulmonary fibrosis (PF) 26.2%, cystic fibrosis (CF) 25.4% and other lung pathologies 20.1%. The chance of transplantation after listing differed by the combined effect of disease category and centre (p<0.001). At 3 years postregistration, 78% of patients with COPD were transplanted followed by 61% of patients with CF, 59% of other lung pathology patients and 48% of patients with PF, who also had the highest waiting list mortality (37%). The chance of transplantation also differed by height with taller patients having a greater chance of transplant (HR: 1.03, 95% CI: 1.02 to 1.04, p<0.001). Patients with blood group O had the highest waiting mortality at 3 years postregistration compared with all other blood groups (27% vs 20%, p<0.001). CONCLUSIONS: The way donor lungs were allocated in the UK resulted in discrepancies between the risk profile and probability of lung transplantation. A new donor lung allocation scheme was introduced in 2017 to try to address these shortcomings.

Patient survival and therapeutic outcome in the UK bridge to transplant left ventricular assist device population.

OBJECTIVE: To study the survival and patient outcome in a population of UK patients supported by an implantable left ventricular assist device (LVAD) as a bridge to heart transplantation. METHODS: Data on all adult patients (n=342) who received a HeartMate II or HVAD as a first long-term LVAD between January 2007 and 31 December 2013 were extracted from the UK Ventricular Assist Device (VAD) Database in November 2015. Outcomes analysed include survival on a LVAD, time to urgent listing, heart transplantation and complications including those needing a pump exchange. RESULTS: 112 patients were supported with the Thoratec HeartMate II and 230 were supported with the HeartWare HVAD. Median duration of support was 534 days. During the study period, 81 patients required moving to the UK urgent waiting list for heart transplantation. Of the 342 patients, 85 (24.8%) received a heart transplant, this included 63 on the urgent list. Thirty-day survival was 88.9%, while overall patient survival at 3 years from LVAD implant was 49.6%. 156 patients (46%) died during LVAD support; the most common cause of death on a VAD was a cerebrovascular accident. There was no significant difference between the two devices used in any outcome. CONCLUSIONS: In a population of patients with advanced heart failure, who have a very poor prognosis, support with an implantable LVAD allowed a quarter to receive a heart transplant in a 3-year period. Overall survival of the cohort was about 50%. With improvement in technology and in post-LVAD management, it is likely that outcomes will improve further.

The interval between brainstem death and cardiac assessment influences the retrieval of hearts for transplantation.

OBJECTIVES: The optimum time after brainstem death (BSD) at which to assess the function of donor hearts is unknown. We hypothesized that a longer interval may be associated with a higher transplantation rate due to improved function. METHODS: Data were obtained from the UK Transplant Registry for the period between April 2010 and March 2015. The time when fixed dilated pupils were first noted in the donor was considered as the time of BSD. Retrieval was defined as the time when the abdominal organs were surgically perfused. RESULTS: BSD to retrieval duration was available for 1947 donors, of which 458 (24%) donated their heart. In the univariable analysis (not adjusting other donor risk factors), evidence was available to suggest that the BSD to cardiac assessment duration had a non-linear association with heart utilization (P < 0.0001). Adjusting for donor risk factors, the relationship remained with longer intervals being associated with increased transplantation (P = 0.0056). The modelled probability of heart utilization had a similar pattern to the observed rate of heart utilization. However, the probability of heart donation began to plateau after approximately 48 h. The analysis of the subset of donors attended by a cardiothoracic retrieval team showed a similar pattern. CONCLUSIONS: These data suggest that time interval from BSD to organ retrieval influences the heart retrieval rate. When the sole reason for declining a donor heart is poor function, a period of further observation and optimization up to 2 days should be considered.