[Intraoperative blood replacement in aortic surgery. Autotransfusion technics]

The performance of increasingly invasive surgical techniques involves higher consumption of blood products, along with associated immunological problems and infections. Measures intended to reduce the use of homologous blood products include autologous transfusion and the application of transfusion criteria. We describe our experience with a group of patients scheduled for aortic surgery.

Three hundred fifty- eight patients were studied prospectively over a period of 60 months, during which various techniques for conserving blood were applied. Up to 2 units were donated before surgery by patients who had baseline hemoglobin (Hb) counts equal to or greater than 13 g/dl. The donated blood was stored in the form of packed red cells (PRC) and fresh frozen plasma (FFP). Plasmapheresis was performed before surgery whenever a loss of 1,200 ml was expected to occur. Intraoperative salvage of lost blood, with the "Cell- Saver" system, was also used in such cases. No patient was given PRC if Hb was equal to or greater than 10 g/dl; nor was plasma given unless analytical levels indicated need.

Between 25 and 33% of the patients, depending on age, required no blood products. In up to 55%, self- donated blood was used. Salvage during surgery conserved around 50% of estimated blood lost. The percentage of autologous blood replaced during surgery increase from 21% in 1989 to 38% in 1993. The amount of autologous plasma used also increased with time, reaching nearly 80% of total plasma infused thanks to the introduction of preoperative plasmapheresis.

The establishment of strict protocols regarding use of blood products and the application of self-donation techniques provided a savings of homologous blood products during the period this study lasted. Preoperative donation of blood was accepted in all cases in which it was indicated and there were no adverse reactions when the autologous blood was replaced.