A. E. Cabrales1, R. S. Mangus1, J. A. Fridell1, C. A. Kubal1 1Indiana University School Of Medicine,Department Of Transplant Surgery,Indianapolis, IN, USA
Introduction: The rate of donation after circulatory death (DCD) liver transplantation has decreased in recent years as a result of inferior graft and patient survival when compared to donation after brain death (DBD) transplantation. Ischemic cholangiopathy (IC) is the primary cause of these inferior outcomes and is associated with a high rate of graft loss, retransplantation and recipient mortality. Development of IC in liver transplant recipients appears to be associated with peribiliary arterial plexus microthrombi formation that can occur in DCD donors. Our center has demonstrated success using tissue plasminogen activator (tPA) flush during DCD organ procurement to prevent the formation of microthrombi and prevent IC. This study investigates the long term impact of tPA flush on graft outcomes and program use of DCD organs.
Methods: All records for liver transplants over a 15 year period at a single center were reviewed and data extracted. DCD organ procurement followed carefully established protocols including a 5-minute wait time after determination of cardiac death prior to initiation of the procurement procedure. The procurement consisted of rapid cannulation of the aorta, clamping of the aorta and decompression through the vena cava. Preservation solution included initial flush with histidine-tryptophan-ketoglutarate solution (HTK), followed by infusion of tPA in 1L NS, then further flush with HTK until the effluent was clear. Total flush volume was less than 5L.
Results: There were 57 tPA procurements (48%) and 62 non-tPA procurements (52%). Patients receiving the tPA grafts were older and had a higher MELD score. The tPA grafts had less cold and warm ischemia time. The grafts procured using tPA had better survival at 7- and 90-days (p=0.09, p=0.06) and at 1-year (95% versus 79%, p=0.01). Cox regression showed significantly better long-term survival for tPA grafts (88% versus 45% at 10-years; p<0.01). Improved outcomes with thrombolytic therapy in DCD liver procurement changed the use of DCD grafts at our center to extended criteria donors who were older, heavier, and out of state. Use of these higher risk DCD donors did not change clinical outcomes.
Conclusion: Our center has shown that optimization of perioperative conditions, including use of an intraoperative thrombolytic flush, significantly lowers the incidence of IC in DCD liver grafts. With improved outcomes, the percentage of DCD grafts at our center has increased, including the use of extended criteria DCD livers, without a worsening of outcomes.
