January 29th, 2014
What’s the Best Blood Transfusion Protocol for Anemic ACS Patients?
CardioExchange’s John Ryan interviews Sunil V. Rao about his approach to blood transfusions in patients with acute coronary syndromes. Dr. Rao recently wrote an editorial on TRANSFUSION-2, a study of the platelet and inflammatory effects of blood transfusions in ACS and non-ACS patients with anemia. Rao’s editorial, coauthored with Matthew W. Sherwood, is published in JACC.
Ryan: What is your practice in patients with ACS and a hemoglobin level ≤8 g/dL? Do you give them transfusions? Under what circumstances would you or wouldn’t you? Does the use or nonuse of bleeding-avoidance strategies (e.g., vascular closure devices, bivalirudin, or a radial approach) influence your decision?
Rao: Our protocol calls for withholding transfusion from asymptomatic patients who have a hemoglobin level >8/dL. If they have symptoms attributable to anemia or the hemoglobin level is ≤8 g/dL, then transfusion is usually administered one unit at a time with re-evaluation of the clinical status and hemoglobin level. We are a very high-volume transradial center, so we try to avoid situations where transfusion may be necessary, but in some patients it is still an issue. The challenge is that our protocol and the European Society of Cardiology guidelines are based on observational data, so we have to recognize that these studies may be confounded by indication. Ultimately, as in all clinical decisions, the risks and benefits must be weighed at the bedside before deciding to order a blood transfusion.
Ryan: Given the discrepant practice and guideline recommendations, how can we get to the bottom of this issue? What sort of trials must we do to define best practices for managing anemia in patients with ACS?
Rao: That is an excellent question, and I think only a randomized trial will ultimately address the issue. The challenge with doing a trial in ACS patients with anemia is that those who would qualify do not fit the profile of a patient who would be considered for the “standard” industry-funded ACS trial. In contemporary clinical practice, where bleeding avoidance strategies are used and the hospital length of stay is quite a bit shorter than in years past, patients who are anemic in the setting of ACS are elderly, frail, and have many comorbidities such as chronic kidney disease. Of course, these are also the patients for whom a transfusion may yield the most benefit or harm. A trial that aims to answer the hemoglobin threshold question in ACS will include very high-risk patients who are generally not approached for clinical trials. It will be difficult, but I think that this is an area where we need solid evidence to guide clinical practice.
JOIN THE DISCUSSION
How does your institution handle blood transfusions for anemic ACS patients?