An evaluation was made of the functional and metabolic condition of red blood cells of blood recovered from the surgical field and postoperative drainage, as well as hematological and biochemical parameters in the same samples of 20 patients who underwent lumbar vertebral arthrodesis (LVA) or knee arthroplasty (KA). The samples from the surgical field and postoperative drainage showed lower hematological values and free plasma hemoglobin levels (PHPL) than controls, but red blood cells showed no abnormalities in morphology or globular osmotic resistance. No significant disturbances in biochemical parameters were found, except for increased serum potassium and phosphate concentrations, which correlated with increased PHBL, indicating a degree of hemolysis. No differences were found in red blood cell transport of glucose and amino acids, or in adenosine-triphosphate (ATP) and 2,3- diphospho-glycerate (DPG) levels, except for ATP in blood from the surgical field. In conclusion, recovered blood is a good source of autologous blood cells because it shows no major biochemical changes and red blood cells conserve their normal functional and metabolic conditions