The Relative Risk of Infection from Transfusions After Arthroplasty

Abstract

For more than a quarter century, orthopaedic surgeons and their patients have been plagued with heightened concerns over complications from blood transfusions. The initial cause for increased caution, starting in the mid-1980s, was the increased awareness of bloodborne transmission of retroviral disease in the form of human immunodeficiency virus (HIV) and the new, near-concurrent ability to identify Hepatitis C separately from Hepatitis A and B1. The sense of burgeoning epidemics of both diseases and the incomplete ability of screening to prevent their transmission led to a new willingness to avoid transfusions at progressively lower hematocrits as well as an explosion of enthusiasm for preoperative autologous blood donations. A second cause for concern, which grew more slowly over the next decade, was that of transfusion-related immunomodulation. Direct clinical measurements of components of the immune system being suppressed by allogeneic blood exposure have been demonstrated; these measurements have been coupled, mostly outside of the orthopaedic literature, with clinical reports of increased rates of infection and more frequent recurrence of tumors2. The most immediate concern for orthopaedic surgeons was the question of increased risk from transfusion for infections after insertion of prosthetic implants. Despite the frequent invocation of such risk as a reason to delay transfusion, the arthroplasty-specific literature has been varied and relatively underpowered on this question. As pointed out by Friedman et al. (one of the two articles discussed in this commentary), the articles that did address this question clinically have been single-center studies compromised by small patient group sizes. In this edition of The Journal, two articles with large patient groups are published that specifically address the question of transfusion-related immunomodulation and the risk for infection after total joint arthroplasty. The issue of sufficient statistical power was addressed in each article by taking advantage of two …