Autotransfusion

Abstract: Background Concerns regarding the safety of transfused blood have prompted reconsideration of the use of allogeneic (from an unrelated donor) red blood cell (RBC) transfusion, and a range of techniques to minimise transfusion requirements. Objectives To examine the evidence for the efficacy of cell salvage in reducing allogeneic blood transfusion and the evidence for any effect on clinical outcomes. Search methods We identified studies by searching CENTRAL (The Cochrane Library 2009, Issue 2), MEDLINE (1950 to June 2009), EMBASE (1980 to June 2009), the internet (to August 2009) and bibliographies of published articles. Selection criteria Randomised controlled trials with a concurrent control group in which adult patients, scheduled for non-urgent surgery, were randomised to cell salvage (autotransfusion) or to a control group who did not receive the intervention. Data collection and analysis Data were independently extracted and the risk of bias assessed. Relative risks (RR) and weighted mean differences (WMD) with 95% confidence intervals (CIs) were calculated. Data were pooled using a random-effects model. The primary outcomes were the number of patients exposed to allogeneic red cell transfusion and the amount of blood transfused. Other clinical outcomes are detailed in the review. Main results A total of 75 trials were included. Overall, the use of cell salvage reduced the rate of exposure to allogeneic RBC transfusion by a relative 38% (RR 0.62; 95% CI 0.55 to 0.70). The absolute reduction in risk (ARR) of receiving an allogeneic RBC transfusion was 21% (95% CI 15% to 26%). In orthopaedic procedures the RR of exposure to RBC transfusion was 0.46 (95% CI 0.37 to 0.57) compared to 0.77 (95% CI 0.69 to 0.86) for cardiac procedures. The use of cell salvage resulted in an average saving of 0.68 units of allogeneic RBC per patient (WMD -0.68; 95% CI -0.88 to -0.49). Cell salvage did not appear to impact adversely on clinical outcomes. Authors' conclusions The results suggest cell salvage is efficacious in reducing the need for allogeneic red cell transfusion in adult elective cardiac and orthopaedic surgery. The use of cell salvage did not appear to impact adversely on clinical outcomes. However, the methodological quality of trials was poor. As the trials were unblinded and lacked adequate concealment of treatment allocation, transfusion practices may have been influenced by knowledge of the patients' treatment status potentially biasing the results in favour of cell salvage.

Abstract: Summary The use of intraoperative cell salvage and autologous blood transfusion has become an important method of blood conservation. The main aim of autologous transfusion is to reduce the need for allogeneic blood transfusion and its associated complications. Allogeneic blood transfusion has been associated with increased risk of tumour recurrence, postoperative infection, acute lung injury, perioperative myocardial infarction, postoperative low-output cardiac failure, and increased mortality. We have reviewed the current evidence for cell salvage in modern surgical practice and examined the controversial issues, such as the use of cell salvage in obstetrics, and in patients with malignancy, or intra-abdominal or systemic sepsis. Cell salvage has been demonstrated to be safe and effective at reducing allogeneic blood transfusion requirements in adult elective surgery, with stronger evidence in cardiac and orthopaedic surgery. Prolonged use of cell salvage with large-volume autotransfusion may be associated with dilution of clotting factors and thrombocytopenia, and regular laboratory or near-patient monitoring is required, along with appropriate blood product use. Cell salvage should be considered in all cases where significant blood loss (>1000 ml) is expected or possible, where patients refuse allogeneic blood products or they are anaemic. The use of cell salvage in combination with a leucocyte depletion filter appears to be safe in obstetrics and cases of malignancy; however, further trials are required before definitive guidance may be provided. The only absolute contraindication to the use of cell salvage and autologous blood transfusion is patient refusal.

Abstract: Preoperative Autologous Donation Preoperative autologous donation was rarely used before the recognition that HIV could be transmitted by blood transfusion. Fifteen years ago, fewer than 5 percent of eligible patients who were scheduled for elective surgery chose autologous blood donation.121 When public awareness of the possibility of transfusion-transmitted HIV became widespread, however, there was concern that too few patients were choosing autologous blood donation as an option. Several states, including California, passed legislation requiring that whenever it was “reasonably” likely that transfusion would be needed, a patient should be informed of all of the options regarding and alternatives to allogeneic . . .

Abstract: Autologous blood donation (ABD) reduces both the real and perceived risks of allogeneic blood exposure, although wasted units increase overall costs. Wastage of autologous blood can be contained by using rational blood ordering and collection strategies. These identify procedures with transfusion requirements, utilizing ABD predeposit in patients undergoing surgery for which the need for blood transfusion has been clearly established, and where the average blood loss for each procedure has been determined. ABD programmes can be optimized by adopting a personalized approach for each individual patient. The predicted and tolerated blood loss is calculated for each patient, and the difference between the two determines the patient's transfusion need. Taking into account the type of surgery, time to surgery and the clinical condition of the patient, the best and most cost-conscious transfusion strategy can then be determined. Options include: reducing the blood loss pharmacologically, transfusing allogeneic blood, using autologous blood from a variety of techniques, using recombinant erythropoietin (epoetin alfa) to increment baseline haematocrit (Hct) or to increase the volume of predonated blood, and using blood substitutes in addition to autotransfusion techniques. Autotransfusion techniques available include ABD predeposit, normovolaemic haemodilution and perioperative salvage. ABD predeposit may be limited by the delay in the natural erythropoietic response to allow recovery of red cells collected. Together with adequate iron support, epoetin alfa accelerates recovery of the Hct and increases the tolerated blood loss. The availability and judicious use of these blood conservation strategies provide for both effective and cost-conscious blood transfusion strategies.