Early Liver Transplant Outcomes Not Impacted by New US Allocation System

By Patricia A. Sheiner MD

May 27, 2022

NEW YORK (Reuters Health) - A new system for allocating liver allografts in the United States, implemented in 2020, has been associated with procurement-related delays but has had no adverse impact on early transplant outcomes, a new study shows.

To assess the effect of Liver Acuity Circle Allocation (AC), researchers compared data from the Organ Procurement and Transplantation Network (OPTN) on 6,230 donation after brain death (DBD) livers procured in the pre-AC period (June 5, 2019, to February 3, 2020) and 10,749 livers procured in the AC period (February 4, 2020, to June 30, 2021).

In both groups, the mean age was 40 and the proportion of procurements involving thoracic organs was 53%. Sixty percent and 65% of donors in the before and after periods, respectively, were male.

The median unadjusted preprocurement time - defined as brain death to cross clamp of the donor aorta -- increased from 47.6 hours (range, 36.2-61.3) to 50.3 hours (range, 38.4-66 hours).

After adjustment, the mean pre-procurement time increased after AC implementation (beta, 3.59; 95% CI, 2.99-4.18; P<0.001). Most donation service areas had a mean increase of 2 to 4 hours. The percentage of donor procurements with preprocurement times of 48 hours or more increased in most regions with and without concurrent thoracic placement.

The median time of the day of donor cross clamp was similar before and after AC implementation, with or without concurrent thoracic organ procurement. Although both the new allocation policy and the COVID surges coincided, the authors do not believe the pandemic had an impact given that COVID testing became routine on admission.

There was no difference in rates of primary nonfunction or early graft failure between the two periods.

The authors recognize that the delays were not substantial and did not impact early graft function. They note, however, that preprocurement times represent a "potential metric to consider in the context of broader organ sharing" and they say future studies should evaluate the "association of pre-procurement delays with family withdrawal of consent for donation, late organ discards, intensive care unit strain when beds are scarce, and financial consequences for donor hospitals reimbursed a fixed amount per donor."

SOURCE: https://bit.ly/3NB50r5 JAMA Surgery, online May 18, 2022.