Preoperative autologous donation for total joint arthroplasty - An analysis of risk factors for allogenic transfusion

Background While autologous blood is commonly predonated to provide replace ment of blood lost in orthopaedic procedures, few studies of patients manag ed with total joint replacement have addressed the problem of which patient s are likely to benefit from an autologous blood-donation program. Methods: A retrospective analysis of 489 consecutive patients who had had a total joint arthroplasty was performed to identify the risk factors for al logenic transfusion and to further define the indications for preoperative autologous blood donation. The operations included 247 total knee replaceme nts (157 unilateral primary, thirty-two revision, and twenty-nine one-stage bilateral primary procedures) and 271 total hip replacements (163 primary and 108 revision procedures). Fifty-four percent (264) of the 489 patients donated a total of 527 units of blood (average, 2.0 units per patient) preo peratively, Results: One hundred and ninety-one patients (39 percent) required a transf usion of autologous blood or allogenic blood, or both. One hundred and thir ty-one patients (27 percent) received autologous blood, and eighty-two pati ents (17 percent) received a transfusion of allogenic blood; twenty-two pat ients (4 percent) received both autologous and allogenic blood. Neither for m of transfusion caused serious complications. Fifty-six percent (295) of t he 527 units of autologous blood were discarded. Autologous donation signif icantly decreased the requirements for allogenic transfusion (relative risk , 0.1; p < 0.0001), It also caused the level of hemoglobin to decrease an a verage of 12.2 grams per lifer from the time before donation to the time be fore the operation (p < 0.0001). Factors that increased the risk for alloge nic transfusion were a revision knee or hip procedure or a one-stage bilate ral primary knee replacement (relative risk, 5.7; p < 0.0001), an initial h emoglobin level of less than 130 grams per liter (relative risk, 5.6; p < 0 .0001), and an age of sixty-five years or older (relative risk, 2.8; p = 0. 02), None of the sixty-seven patients who had a primary knee or hip arthrop lasty and an initial hemoglobin level of 150 grams per liter or more requir ed an allogenic transfusion, In addition, none of the sixty-three patients who had a primary arthroplasty, an initial hemoglobin level of between 130 and less than 150 grams per lifer, and an age of less than sixty-five years required an allogenic transfusion. Eighty-three percent (115) of the 138 a utologous units donated by the seventy patients in these two groups were di scarded. These wasted units accounted for 39 percent of the 295 discarded u nits for the entire study sample, Conclusions: The efficiency of collection of autologous blood can be improv ed by identifying patients who have a very low risk of transfusion accordin g to the type of arthroplasty, the initial level of hemoglobin, and age. pa tients who have an initial hemoglobin level of at least 150 grams per lifer or an initial hemoglobin level of between 130 and 150 grams per lifer and an age of less than sixty-five years have a minimal risk of needing a trans fusion during or after a primary total joint replacement. These patients sh ould be apprised of their low risk so that they can make an informed decisi on regarding preoperative autologous donation.