Abstract
The purpose of this study was to evaluate the effects of liposome encapsulated hemoglobin named “Neo Red Cells (NRC)” on the canine hemorrhagic shock model and its safety for the vital organs in a whole blood exchange model. Under mechanical ventilation inhaling room air, hemorrhagic shock was induced and then NRC was transfused in dogs. The same procedure was repeated 3-5 times. After NRC transfusion, the peripheral vascular resistance was reduced due to the low viscosity of NRC thus relieving the burden on the heart. The oxygen-transport capacity of NRC was 2-4 times that of natural erythrocytes because the affinity for oxygen was regulated by appropriately adding inositol hexaphosphate as allosteric effector. Two dogs whose blood was exchanged with NRC (exchange rate was from 84 to 90%) have been living over a year without any side effect (one has survived 16 months, the other 14 months). A dog sacrified on the 15th postoperative day for autopsy, microscopically showed no side effects in vital organs. We conclude that NRC is more suitable than natural blood for treatment of hemorrhagic shock and safe for vital organs.
