2. Materials and methods
Porcine blood was collected through an aseptic closed
system from 60 animals weighing 90–100 kg. A ‘‘vampire’’
knife connected to a non-toxic hose was used for
bleeding. Blood was collected in a large stainless steel can
to which a mechanical stirring system was connected.
During exsanguination sodium citrate solution (0.5%
relative to blood volume) was added to the system.