Although an HPC infusion can be seen as a special blood transfusion, it differs in several points. Thawed blood transfusions contain DMSO, they are cold when infused, they have a high osmolality and they contain cell debris and some free hemoglobin. ABO-compatible products are sometimes needed and infused because of the importance of HLA matching. Adding the cryoprotectant, alterations resulting from freezing and thawing and transfusions across the ABO barrier require special precautions, during and after the transfusion.