Introduction: In recent years, transplant medicine has developed interventional organ donation research as a way of producing better outcomes for transplant recipients. However, this research is hampered by ethical complexities, particularly related to consent. Little is known about how relatives and specialist nurses experience the consent process around this type of research. We aimed to explore consent processes for interventional donor research in the context of a UK trial of statins in organ donors declared dead by neurological criteria (the SIGNET trial) and with the introduction of deemed consent in UK jurisdictions.  
Method: Twenty-nine narrative interviews were conducted with thirty-four donor family members approached about consenting their relative into SIGNET. Narrative style interviews were also conducted with eleven Specialist Nurses in Organ Donation (SN-ODs) and Specialist Requestors (SRs). The dataset was analysed thematically.  
Results: Our findings highlight that the entire consent conversation, including discussions around donation and research, was experienced as too long, with overwhelming levels of detail needing to be taken in (for relatives) and provided (by SN-ODs/SRs). This led to relatives experiencing ‘consent fatigue’ and to relatives and SN-ODs/SRs de-prioritising research over securing donation consent. In response to these challenges, SN-ODs/SRs worked hard to mitigate overwhelm and sensitise their practice to families’ needs, whilst also trying to cover required consent information.     
Conclusion: We argue that specific consent processes for interventional donor research are likely adding to the complexity of deemed consent processes and are having potentially detrimental effects on donor relative decision-making, and for the work of SNOD/SRs. We advocate for consent for interventional donor research in the UK to be considered as a relational process, which should be integrated into a simplified donation consent process, which is sensitised to the needs of all involved.