Justifying Nonstandard Exception Requests for Pediatric Liver Transplant Candidates: An Analysis of Narratives Submitted to the United Network for Organ Sharing, 2009-2014.

Nonstandard exception requests (NSERs), for which transplant centers provide patient-specific narratives to support a higher Model for End-stage Liver Disease/Pediatric End-stage Liver Disease score, are made for >30% of pediatric liver transplant candidates. We describe the justifications used in pediatric NSER narratives 2009-2014 and identify justifications associated with NSER denial, waitlist mortality, and transplant. Using United Network for Organ Sharing data, 1272 NSER narratives from 1138 children with NSERs were coded for analysis. The most common NSER justifications were failure-to-thrive (48%) and risk of death (40%); both associated with approval. Varices, involvement of another organ, impaired quality of life, and encephalopathy were justifications used more often in denied NSERs. Of the 25 most prevalent justifications, 60% were not associated with approval or denial. Waitlist mortality risk was increased when fluid overload or "posttransplant complication outside standard criteria" were cited and decreased when liver-related infection was noted. Transplant probability was increased when the narrative mentioned liver-related infections, and fluid overload for children <2 years old; it decreased when "posttransplant complications outside standard criteria" and primary sclerosing cholangitis were cited. This analysis provides novel insight and suggests targets for future consideration in outcomes research and exception criteria. Changes in the allocation system are needed to ensure equity and optimize outcomes for all pediatric candidates.