Mastering the Narrative: Precision Reporting of Risk and Outcomes in Liver Transplantation

Liver transplantation is associated with a high risk of postoperative complications due to the complexity of the surgical procedure, recipient disease severity and wide range of graft quality which remains somewhat unpredictable. However, survival rates after transplantation continue to improve and the focus has thus turned to other clinically relevant endpoints including posttransplant complications, patient quality of life and costs. Procedures like liver transplantation offer the entire spectrum of postsurgical events, even in donor-recipient constellations deemed of low risk within recently defined benchmark criteria. The Clavien-Dindo classification and the Comprehensive Complication Index (CCI®) were established to assess postoperative morbidity and are widely utilized across surgical specialties. However, these scores unfortunately are associted with observer variability when used in practice, mainly due to the lack of uniform definitions. Interventions required to treat a specific complication are the main drivers of clinically relevant complications, which may result in under- or over-scoring of posttransplant events. The number and grade of complications is frequently used as a metric assessing specific donor-recipient-risk-profiles and in assessing new approaches such as machine perfusion. Thus, accurate stratification is critical to comparing various potential risk factors. The concept of Benchmarking was recently introduced in surgery and transplantation as a mechanism of standardizing expected donor/recipient risk with outcomes within the first year after surgery. The management of complications, however, differs significantly worldwide, as does the rating scale assigned to various complications. This may lead to inhomogeneous interpretation of study results, leading to difficulty in assessing the clinical effects of novel preservation technologies and other therapeutics in liver transplantation. It also limits generalizability of study findings between countries, centers, and even providers. This article critically discusses frequent challenges associated with risk and outcome assessment following major surgery with a particular focus in liver transplantation.