Systemic effects of intraoperative autotransfusion

The hematological effects of autotransfusion have not been well characterized. A canine model was used in which a controlled 2000-ml blood loss was effected into the open peritoneum and replaced either by autotransfusion, using one of two devices, or by homologous transfusion. In each group hematological data were collected before, during, and after the operation. None of the parameters measured showed significant differences between the two autotransfused groups. However, intraoperative values for prothrombin time and activated partial thromboplastin time were significantly prolonged in the autotransfused groups compared with the homologous transfusion group. Fibrinogen levels and platelet counts fell significantly from baseline levels in the intraoperative period, but rose above even baseline levels postoperatively. White blood cell counts remained unchanged intraoperatively, but rose significantly and remained elevated at 24 hours and 1 week. No significant differences exist between the effects produced by the two autotransfusion systems. It is clear that prothrombin time and activated partial thromboplastin time are prolonged intraoperatively in the autotransfusion groups, whereas these parameters are unaffected by homologous transfusion.