Bleeding Following Frozen Elephant Trunk Surgery: A Proposed Reporting Dataset and Research Agenda

Perioperative bleeding after frozen elephant trunk (FET) surgery is reported using heterogeneous endpoints. This structured narrative review examines bleeding sources, measurement and haemostatic management, prioritising recent literature while retaining established landmark definitions. Twelve primary FET clinical publications are tabulated, with technical reports and wider cardiac-surgery evidence providing context. Re-exploration, postoperative drainage, estimated blood loss, transfusion and fabric oozing describe related but distinct phenomena. Established classifications, particularly the Universal Definition of Perioperative Bleeding (UDPB), provide a severity-reporting reference and should not be displaced by a new FET scale. We propose six parallel reporting domains: procedural context; bleeding measurement; haemostatic status; verified source; treatment exposure; and outcomes.. The study-level mapping shows that published FET reports often permit extraction of drainage, re-exploration or treatment exposure, whereas haemostatic status and a directly verified bleeding source are rarely recoverable from published reports. The dataset therefore makes these information gaps explicit and supports prospective evaluation; it does not infer an anatomical source from laboratory findings, drainage or treatment. The proposed reporting dataset is not a validated severity scale or treatment algorithm.