**1. Introduction**

108 Recent Advances in Arthroplasty

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Orthopedic surgery is one of most blood-consuming surgical specialties since it is associated with a significant preoperative hemorrhage requiring frequent allogeneic blood transfusions. A special mention needs to be done to hip and knee arthroplasty, complex rachis arthrodesis and tumor-pathology removal. The intervention on older and higher-risk patients has raised the demand on allogeneic blood to such levels that even Blood Banks are unable to attend. Besides the high cost, using allogeneic blood has its risks, such as immunosuppression, patient's wrong identification, transfusion reactions or the possibility of infectious disease transmission. This imbalance between blood demand and availability, together with the awareness about potential risks of blood transfusions and the continuous advances both in technology and pharmaceutics, should lead us to extreme changes in transfusion politics; developing a series of therapeutic measures to reduce blood transfusion to minimum, leaving its use only when it is strictly necessary, especially in scheduled surgery.


Table 1. Blood-saving techniques during perioperative time.

Blood Transfusion in Knee Arthroplasty 111

Iron-deficiency anemia affects approximately 25% of world population. Furthermore, there is a status defined as 'functional iron-deficient states', which is described as a situation where iron deposits are normal (or even increased), but iron supply to bone marrow is inadequate to satisfy the erythroid precursor demands; and another anemia associated to 'chronic processes' where erythropoiesis is deficient because of proinflammatory cytokines-

Nowadays it has been proven its high profitability and efficiency index, mainly to optimize or as support in the erythropoietin treatment and autologous predonation. Administration of oral iron is effective in decreasing allogeneic blood transfusions and/or the number of transfused patients in orthopedic major surgery (Okuyama et al., 2005). Orally or intravenous use of iron will depend at the moment in which the treatment is taking place, oral iron absorptive capacity and existence of any gastric disease that could contraindicate oral iron treatment (Cuenca et al., 2004). If treatment is done with intravenous iron, once it is

The total amount of administered iron will depend on initial hemoglobin value and existence of an iron-deficient condition. If using saccharose iron, dosage varies from 100 to 200 mg in alternate days, with a maximum dose of 600 mg per week and 200 mg every 2 days. At present there is also carboxymaltose iron, which contains greater amounts of iron (500-1000 mg) to administer in a single dose. In case of a folic acid and/or vitamin B12

This means the presurgical patient's blood predonation or autodonation. Some weeks prior to intervention, a blood extraction (one or more units of blood) is performed to the patient

To be included in the program the patient must fulfill both medical and analytical special requirements; hemoglobin levels before starting predonation process above 11 mg/dl, as well as an appropriate programming of surgery to avoid expiration of the predonated units (35 days - maximum time permitted for storage). Due to this fact, quite a reasonable amount of patients who have undergone autologous blood donation preoperatively, reach surgery time with hemoglobin values under their initial levels (before predonation), therefore increasing transfusion requirements. The patient carries out the donations once or more times during the days and weeks prior to intervention. 350-400 mL extractions are made not less than 3-day intervals, which is the time needed for protein synthesis and mobilization and to return to normal. This way, they can benefit from erythropoiesis stimulation with

Despite the fact that this technique was at its peak during the nineties, its use has been diminishing progressively for several reasons. In first place, the high number of blood bags that were dismissed because of an imbalance between extracted bags and transfusion requirements, since a good coordination in surgery programming and between all professionals taking part is needed. This difficulty has made this method a very expensive one in resource-consumption and less effective than it was thought to be at first. On the other hand, the establishment of intravenous iron and erythropoietin, decrease in transfusion threshold and improvement of the surgical method too, have pushed into the background autologous donation preoperatively, leaving it as last option in some cases such as complex spinal surgery with a mass blood loss forecast and those patients whose blood

mediated mechanisms.

finished we must prescribe oral iron.

**2.2 Autologous blood predonation** 

group have compatibility difficulties.

to be used at his/her surgery or postoperatively.

deficiency we must supply substitutive treatment to correct it.

erythropoietin. All patients must receive an appropriate iron supplement.

The aim of this chapter is to inform on saving techniques of hematic components and its implantation in scheduled orthopedic surgery, summarized in table 1.
