Previous studies reported on both visible and invisible particles in University of Wisconsin (UW) solutions. Those particles originated from components of the bags. In recent clinical observations we noticed macroscopically visible, indissoluble particles in UW bags reaching subzero temperatures during transportation of organs and preservation solutions. In an experimental model we examined whether those particles could be detected following perfusion of abdominal organs with established perfusion solutions. UW-, HTK- or physiological saline solutions reached -3°C to -0.5°C under conditions frequently applied during transportation. UW solutions demonstrated the accumulation of visible, indissoluble crystals and were subsequently used for the perfusion of abdominal organs in LEW rats. After perfusion with UW solutions stored at freezing temperatures, crystals were detected in all abdominal organs localized in and around vessels, bile ducts, glomeruli and in the interstitium of harvested livers, kidneys and pancreas. By spectroscopy, we were able to characterize crystals as adenosine. A 40-mm pore-size filter eliminated crystals from UW solutions. Crystals were absent in organs perfused with HTK- or saline solutions kept at subzero conditions. UW solutions can reach subzero temperatures under commonly used transportation conditions. Under these conditions, visible crystals accumulate and can be detected in abdominal organs of an experimental system.
“Although the manufacturers of UW solutions state that the solutions should be stored at 2–8.C, in the clinical situation preservation solutions and organ bags are frequently surrounded by frozen saline bags during transportation. Under these conditions, subzero temperatures occur, and macroscopically visible and indissoluble particles have been observed in UW solutions.”
“In summary, our results demonstrate for the first time the accumulation of intravascular and interstitial crystal deposits in intra-abdominal organs following perfusion with UW solutions reaching subzero temperatures under frequently applied clinical transporting conditions. Adequate storage temperatures of both grafts and perfusion solutions, in addition to the utilization of filter systems, seem of major importance in avoiding potential graft injuries.”
Stefan G. Tullius, Alexander Filatenkow, Dietmar Horch, Thomas Mehlitz, Anja Reutzel-Selke, Johann Pratschke, Thomas Steinmüller, Andreas Lun, Hussein Al-Abadi and Peter Neuhaus;
Transplantation Proceedings, 34, 2320 (2002)