Reducing blood loss and the need for blood transfusion, especially allogeneic transfusion, has long been a goal of surgeons across all specialties. Allogeneic transfusion is associated with a host of negative effects, including transfusion reactions, immunocompromise, an disease transmission. Decreasing transfusion rates have been demonstrated for a variety of operations, though the trends in transfusion following spinal fusion have not been explored. Drs. Yoshihara and Yoneoka attempted to do just this using the National Inpatient Sample database. They identified patients in the database from 2000 to 2009 who had undergone spinal fusion and then determined the rates of pre-donated autologous, perioperative autologous (i.e. Cell-Saver), and allogeneic transfusion. They found that the overall transfusion rate increased marginally, from 7.4% to 10.6% (not statistically significant), while the rate of pre-donated autologous transfusion decreased (2.6% to 0.7%), and the rate of allogeneic transfusion increased from 4.3% to 8%. There was a trend towards increasing use of perioperative transfusion (1.3% to 2.8%, not significant). Not surprisingly, age under 17 or over 85, increased magnitude of surgery (number of levels fused, front-back surgery), female gender, and comorbidities all increased the likelihood of transfusion.
This article is interesting as, despite the efforts aimed at decreasing blood loss and allogeneic transfusions (i.e. Cell-Saver, pharmacologic agents, and less invasive surgery), the rate of transfusions is actually trending up. Given that transfusion is more likely in larger magnitude surgery and in older, sicker patients, it is possible that changes in the case and patient mix could be driving the observed increases. While this study did not control for case and patient mix, such an analysis might yield a different result. More recently, hospitals have been using stricter transfusion protocols (i.e. allowing hemoglobin levels to drift down to 7.0 in healthy, asymptomatic patients), and extending the analysis beyond 2009 may demonstrate the effect of these protocols. Given that transfusion rates in other fields have been trending down over time, this analysis should draw attention to the issue in spine surgery and warrant further investigation. Observational database studies such as this are useful to generate hypotheses, however, prospective randomized trials are needed to determine causal relationships. Hopefully it will serve as the impetus for further studies of blood management strategies to determine which approaches yield the best outcomes and are cost-effective.
Please read Dr. Yoshihara’s article in the Febrauary 15 issue. Does this article change you view of how blood transfusions are used in spinal fusion? Let us know by leaving a comment on The Spine Blog.
Adam Pearson, MD, MS
Associate Web Editor