International evaluations of thoraco-abdominal normothermic regional perfusion protocols according to neurophysiological and cardiovascular implications

Normothermic regional perfusion (NRP) is recognized as a surgical innovation that may improve the viability of organs following circulatory death for individuals who require transplantation. Abdominal normothermic perfusion (A-NRP) and thoraco-abdominal NRP (TA-NRP) are procedures that ensure adequate oxygenated blood flow to organs in situ before removal. A-NRP differs from TA-NRP as the perfusion is limited to the liver, pancreas, and kidneys, whereas TA-NRP also includes perfusion of the heart and lungs. TA-NRP remains controversial, with ethical and legal challenges, particularly concerning the re-establishment of cerebral blood flow and potential violations of the dead donor rule (DDR). Debates regarding the ethical differences between A-NRP and TA-NRP have been evaluated in other publications but are not within the scope of this paper. This paper examines the implications of the methodological differences of TA-NRP between the United States and other European nations, as the US recently adopted its use in 2020. These implications are evaluated according to research and surgical ethics frameworks given the limited empirical study of TA-NRP within human models. Future directions and recommendations are proposed to ensure adequate protection of human organ donors in the US context, similar to those implemented in European TA-NRP protocols.