CHANGING BLOOD USE IN THE AIDS ERA - THE CASE OF ELECTIVE HIP-SURGERY

Background: Concern about the transmission of human immunodeficiency v irus via blood has substantially increased the public's anxiety about the safety of the blood supply and has encouraged practices to minimiz e risks deriving from transfusions. Study Design and Methods: To asses s changes in transfusion practices in elective surgery as awareness of transfusion-transmitted human immunodeficiency virus emerged, 80 rand omly selected patients per year undergoing elective total hip replacem ent in five calendar years between 1977 and 1989 at a large university teaching hospital were studied. Results: Total blood use decreased si gnificantly from an average of 3.3 units per patient in 1977 to 2.1 un its per patient in 1989 (p 0.0003). Autologous blood use increased fro m essentially zero in 1977 to 82 percent of total blood use in 1989 (p <0.0001). The threshold hematocrit for postoperative transfusion of al logeneic blood (defined by use of logistic regression models) decrease d from 30.1 percent (0.30) In 1977 to 26.7 percent (0.27) in 1989 (p = 0.01). As a result of these changes, the proportion of patients expos ed to allogeneic blood decreased from 90 to 16 percent across the stud y period (p<0.0001). The dramatic decrease in the use of allogeneic bl ood in elective total hip replacement surgery during the study period was due to decreased demand for blood during and after the operation a nd to a striking shift in the blood supply from allogeneic to autologo us sources. Conclusion: These findings demonstrate that physicians can appropriately alter practices when there are perceived health risks.