Retrospective Review of Calgary Zone Hgb Transfusions for Iron Deficiency Anemia and Concordance with Clinical Guidelines

Student Researcher:
Zohaib Siddiqi

Supervisors / Principle Investigators:
Eddy Lang
Daniel Grigat

Additional Authors:
Eddy Lang
Daniel Grigat
Shabnam Vatanpour

MD Class of 2021


Background: Choosing Wisely has released guidelines outlining under what circumstances transfusion should be given for patients with Iron Deficiency Anemia (IDA). To date, no study has examined the number of transfusions (indicated and unindicated) in Calgary Zone emergency departments (EDs).

Methods: We analyzed 8651 IDA patient encounters from 2014–2018 at four centers in the Calgary Zone. A transfusion was unindicated if the patient’s hemoglobin (hgb) was ≥70 g/L AND if the patient was hemodynamically stable. We used descriptive statistics to get the summary of transfusions across sites and across years and performed chi-squared tests to determine if there were significant differences between site, time-period, hemoglobin level.

Results: In total, 990 (11.4%) of the encounters received transfusions; 711 (71.8%) were indicated while 279 (28.1%) were avoidable. Out of the transfusions that were indicated, 230 (32.3%) were given to patients with a hgb<70 and 481 (67.7%) were given to patients with a hgb>70 but who were hemodynamically unstable. There were 3.2 avoidable transfusions per 100 IDA presentations and 28.2 avoidable transfusions per 100 total transfusions. There was a significant difference between the Year and number of potentially avoidable transfusions (p=0.004). There was a significant difference of Hgb level and whether a transfusion was potentially avoidable (p<0.001).

Discussion: Our data suggest that the number of potentially avoidable transfusions has decreased since the release of guidelines and that there is a higher likelihood of an unavoidable transfusions being given the lower the Hgb level. We intend to use these results to create a safer and more cost-effective approach to managing IDA in the ED.