Research teams at National Defense Medical College, Waseda University, and Nara Medical University have succeeded for the first time in the world in resuscitation of hemorrhagic shock using hemostatic nanoparticles and oxygen-carrying nanoparticles.
In the case of traumatic massive bleeding caused by a traffic accident, rapid mass transfusion is the key to lifesaving.Overseas, blood transfusions with a good balance of red blood cells (oxygen transport), platelets (hemostatic), and plasma (maintaining circulatory volume) are attracting attention in order to improve the life-saving effect.However, since platelets are difficult to store and have a short storage period, mass transfusion in an emergency is difficult.It is difficult to secure a sufficient amount of blood transfusion for red blood cells depending on the region and situation.
In the research team, Waseda University is promoting the development of nanoparticles (platelet substitutes containing adenosine diphosphate) that gather at the bleeding site and promote the formation of platelet thrombi, and research on their hemostatic ability.Nara Medical University has developed nanoparticles (red blood cell substitutes containing human hemoglobin) that have almost the same oxygen carrying capacity as red blood cells.This time, the research team tried to save the life of a rabbit with severe hemorrhagic shock with coagulopathy using these two nanoparticles (2-2 nanometers in diameter).
First, an acute thrombocytopenia was induced, and the liver of a rabbit whose bleeding did not stop was injured and bleeding.Then, while compressing the bleeding site for 5 minutes, a platelet substitute was intravenously administered together with plasma.The pressure was released, the presence or absence of hemostasis was confirmed, and a red blood cell substitute was administered for extreme anemia due to bleeding to see a lifesaving effect.As a result, 10 out of 6 birds were successfully saved.The same life-saving effect as the platelet transfusion and red blood cell transfusion groups (10 out of 7 birds were saved) was obtained (all birds died in the untreated group).
These blood-stopping and oxygen-carrying platelet and erythrocyte substitutes have excellent storage stability and are expected to be useful not only in hospitals but also in pre-hospital resuscitation of patients with traumatic bleeding.
