Last month’s article on Guiding Transfusion Guidelines: Part 1 covered the general concepts of implementing clinical practice guidelines. Appropriate transfusion decisions are a critically important and often overlooked part of the transfusion safety chain from donor to patient1, so evidence-based transfusion guidelines are a necessary piece of blood utilization infrastructure. Perhaps the biggest problem hospitals face is to actually assign hard and fast numbers for transfusion criteria, often referred to as “transfusion triggers,” for specific blood products. In general, physicians don’t like being told what to do (the issue of autonomy) because of the years of training and experience required to practice medicine. Along those same lines, physicians on committees are also uncomfortable telling other physicians what to do, particularly if they aren’t in the same specialty. This general discomfort about being proscriptive with regard to physician practice is amplified by the standard academic comment that physicians should never use transfusion triggers; they should instead carefully assess the physiologic status of each patient individually. The end result is that many hospitals create transfusion guidelines that are purposely broad, and in the end these guidelines provide little help to the clinician trying to make a reasoned decision at the bedside or to the utilization review nurse trying to assess transfusion appropriateness.
I don’t mean to offend physicians in academic medicine because they have done a tremendous amount to advance our transfusion knowledge, but the statement to never use transfusion triggers is not based in reality. There are two facts in the real world of transfusion medicine, validated on a daily basis by our consulting group:
- All physicians, whether they realize it or not, use transfusion triggers based upon the comfort level obtained during their informal training, so hospitals need to reset comfort levels and encourage physicians to center decisions on more current and evidence-based transfusion criteria.
- Most physicians in the US have never received formal training in medical school or residency on blood component therapy, so their transfusion training lacks standardization and is more aligned with habits, misconceptions and myths;
In particular, the transfusion trigger for red blood cells has been moving to a more conservative level as a result of the findings of the TRICC trial that we discussed in part 1 of this series. Based upon this prospective randomized trial, as well as the ACP Practice Guidelines2, we established the transfusion criteria for stable patients without active cardiac disease as a hemoglobin of 7 gm/dL at St. Vincent Indianapolis back in 2001, and we set a hemoglobin of 8 gm/dL for patients with active cardiac disease. At the time, there were a number of objections that certain patient populations required more liberal transfusions than these criteria because the patients had “special” requirements (pulmonary, cardiac, neurosurgery, plastic surgery, orthopedic surgery, etc), but there was no compelling evidence to support these contentions. What we now know is that while anemia may be harmful in many patients, transfusions are increasingly found to be ineffective and can actually worsen patient outcomes. The paradox seems to be that high risk patients are harmed by anemia yet suffer most from the adverse effects of blood transfusions, suggesting that anemia management is our most effective strategy. At the bottom of this article is a link to download the St. Vincent transfusion guidelines we put in place in 2001. We are currently going through a review and will likely do some minor revisions, but they have served us well for the past 10 years. I am also including some other excellent references3-6 that can help develop transfusion guidelines at your institution.
The bottom line with transfusion guidelines is that you can’t please everyone, you have to use the best information available, you have to draw a line somewhere, and most importantly these are guidelines not standards. A physician can still make a clinically appropriate and justifiable transfusion decision outside the guidelines; they simply need to document their rationale (deviate but document). I suggest that at the bottom of each group of transfusion indications there should be a final line that states “other indication – please list”. This allows the physician to transfuse “off label” as long as there is documentation to support the transfusion decision. It is then the job of the blood utilization committee to track these “off label” transfusions and over time decide whether they fall into one of three categories:
1) Infrequent random use: no action required
2) Systematic use by an individual physician: requires targeted education
3) Systematic use by many physicians for a common indication: suggests the need to review and possibly add a new approved indication.
- Dzik WH. Emily Cooley Lecture 2002: transfusion safety in the hospital. Transfusion 2003;43:1190-9.
- Welch HG. Prudent strategies for elective red blood cell transfusion. Ann Intern Med 1992;116:393-402.
- America’s Blood Centers. The transfusion trigger updated: current indications for red cell therapy. ABC Bulletin 2003;6(2).
- American Society of Anesthesiologists. Practice guidelines for perioperative blood transfusion and adjuvant therapies: an updated report by the Task Force on Perioperative Blood Transfusion and Adjuvant Therapies. Anesthesiol 2006;105:198-208.
- Rao SV. Relationship of blood transfusion and clinical outcomes in patients with acute coronary syndromes. JAMA 2004;292:1555-62.
- Napolitano LM. Clinical practice guideline: red blood cell transfusion in adult trauma and critical care. Crit Care Med 2009;37:3124–3157.