EFFECT OF LIPOSOME-ENCAPSULATED HEMOGLOBIN, NEO RED-CELLS, ON HEMORRHAGIC-SHOCK

We examined the effects of liposome-encapsulated hemoglobin, neo red c ells (NRCs), on hemorrhagic shock in a canine model, The dogs were div ided into the three groups according to treatment. In group 1, compose d of six dogs, NRCs were substituted for blood without shock being ind uced; in group 2, composed of six dogs, NRCs were administered immedia tely after mild shock had been induced by exsanguination through the v ein; and in group 3, composed of seven dogs, NRCs were administered af ter they had been left untreated for 30 min inducing severe shock, In group 2, administration of NRCs at a dose equivalent to the volume of exsanguinated blood improved the symptoms of shock; however, in group 3, a dose of NRCs 1.6-times the volume of exsanguinated blood was requ ired, Peripheral vascular resistance (PVR) decreased after NRC adminis tration in groups 1 and 2, but increased in group 3, On the other hand , the cardiac index (CI) increased in groups 1 and 2, and decreased in group 3, Concerning oxygen kinetics, there were no increases in the o xygen requirements or arteriovenous differences of the oxygen content per hemoglobin (AV/Hb) for NRCs in groups 1 and 2, Conversely, in grou p 3, the oxygen requirements increased and the NRCs compensated for th e decrease in CI with an increase in AV/Hb by enhancing the oxygen tra nsport efficiency to cope with the increased oxygen requirements.