AEROBIC PRESERVATION OF ORGANS USING A NEW PERFLUBRON LECITHIN EMULSION STABILIZED BY MOLECULAR DOWELS/

The purpose of the study reported here was to explore a new strategy f or the aerobic preservation of transplants using stable concentrated f luorocarbon emulsions as an oxygen delivery system. Fluorocarbons (FCs ) are synthetic molecules, chemically and biologically inert, with a h igh oxygen-dissolving capacity. As they do not mix with water, it is n ecessary to emulsify them for intra-vascular use. Perfluorooctyl bromi de (or perflubron) can be emulsified with egg-yolk phospholipid (EYP), a nontoxic emulsifiant. The recent adjunction of amphiphilic fluoroca rbon-hydrocarbon diblock molecules allows the obtaining of stable emul sions, By contrast with hemoglobin, fluorocarbons release oxygen follo wing Henry's linear law rather than Barcroft's sigmoid curve. Release of oxygen by the FCs is only slightly influenced by temperature, which is an advantage for the preservation of organs. We tested a new 90% w /v fluorocarbon stem emulsion (perflubron/EYL/F6H10) diluted to 36% w/ v with a hydroelectrolytic solution containing albumin, on four multip le organ blocks (MOBs; heart-lungs, liver, pancreas, kidneys, small in testine) of rats (EMOBs). Five control MOBs were perfused with a 50% v /v mixture of rat-blood and Krebs solution (KBMOBs). The lungs were ve ntilated with a FiO2 = 100%. In all cases the survival of the MOBs was greater than 210 min, with stable hemodynamics and preserved hydroele ctrolytic and acid-base balances. The levels of lactate, amylase, and CK of the EMOBs were inferior (P < 0.05) to those of the KBMOBs betwee n the first and the second hour, The diuresis of the EMOBs was higher (P < 0.05) than that of the KBMOBs (5.65 +/- 1.76 vs 1.21 +/- 0.28 mg/ min), The production of bile, and the AST and ALT levels, were not sig nificantly different. The PaO2 of the EMOBs was higher (P < 0.01) than for the KBMOBs, In normothermy, the maintenance of an aerobic metabol ism using the FC emulsion caused less damage to the organs. Aerobic pr eservation of organs using FC emulsions therefore appears to be an att ractive alternative to the presently used cold ischemia. (C) 1996 Acad emic Press, Inc.