DEVELOPMENT OF A NOVEL EX-VIVO RENAL PERFUSION CIRCUIT WITH NORMOTHERMIC BLOOD

Abstract

The shortage of organs is a major limitation in transplantation. A possible solution to this problem is to improve the procurement techniques and to develop new methods to preserve and store organs. We developed an ex vivo renal perfusion system in which resuscitation of the organs was attempted with the ultimate goal of mimicking normal renal physiology, overcoming the ischemic barriers in organ retrieval and storage. Methods: Excised swine kidneys were placed in a plastic ex-vivo circuit attached to the femoral vessels of the donor with a mini-roller pump to regulate perfusion flows at 100 ml/min to avoid high perfusion pressures. Organs were studied during 4 hours of reperfusion and compared to control organs (in-situ), with temperature maintained at 37.5 °C. The reperfusion parameters studied include perfusion pressures, renal artery blood flows (RAF), vascular resistances (RVR), urine output (UO) and histologic evaluations. Results: RAF was restored early after reperfusion and maintained at 60–70% of baseline. UO was re-established during the first 10min of reperfusion and maintained during the full experiment, with lower values for the study group. RVR was maintained at the same value during reperfusion, with slightly higher values for the study group. Conclusion: With this system, diuresis was restored and the resuscitated ex vivo organs exhibited ongoing metabolism rather than being inhibited by traditional methods. The ability to quantify and analyze urine during reperfusion and preservation facilitates the assessment of organ function and viability before transplantation.