Whole blood donation

Blood, blood cells, blood plasma and their function

Blood is a component of our organism, half of which consists of yellowish blood fluid (blood plasma), half of which consists of different blood cells: red blood cells (erythrocytes, which are also responsible for the red colour of the blood), white blood cells (leukocytes), and platelets (thrombocytes), the smallest cells of the human organism. All these blood components perform different functions: Erythrocytes act as oxygen carriers, leukocytes fend off bacteria, fungi and viruses, thrombocytes seal off injuries in interaction with blood plasma. Blood plasma serves as a transport medium for cells and nutrients. A pronounced lack of any of the aforementioned blood components can lead to the death of the patient. Modern transfusion medicine makes use of the different functions by breaking down the whole blood into individual components and then providing each patient with the component that he or she lacks.

Whole blood donation technique

After puncturing an arm vein, a total of 450 ml of blood flows into a sterile PVC multiple bag system consisting of a storage bag for frozen plasma and a storage bag for the red blood cells. The latter bag also contains a nutrient solution, so that the erythrocytes can be kept for up to 6 weeks if sufficiently cooled (4°C). The frozen plasma can be stored at -40°C for up to 2 years.