CE: Recognizing Transfusion-Associated Circulatory Overload

ABSTRACT

Transfusion-associated circulatory overload (TACO) is the leading cause of transfusion-related deaths in the United States, accounting for more than 30% of fatalities reported to the Food and Drug Administration between 2016 and 2020. However, TACO is widely considered to be an underdiagnosed and underreported complication of blood transfusions, and its exact incidence is unknown. One of the reasons for this is a lack of recognition of TACO and its signs and symptoms, especially as the definition of TACO has been updated twice since 2018 without full dissemination to nurses, who are responsible for bedside care of patients during and following blood transfusions. This article seeks to bridge this gap by discussing the updated definitions and signs and symptoms of TACO, as well as the management of this treatable blood transfusion reaction.

Differential effects of speed and volume on transfusion-associated circulatory overload: A randomized study in rats

BACKGROUND AND OBJECTIVES

Transfusion-associated circulatory overload (TACO) is the primary cause of transfusion-related mortality. Speed and volume of transfusion are major risk factors. The aim of this study was to investigate the interaction of red blood cell (RBC) transfusion speed and volume on the development of TACO.

MATERIALS AND METHODS

A validated model for TACO in anaemic Lewis rats with an acute myocardial infarction was used. The effect on pulmonary hydrostatic pressure of one, two or four units of packed RBCs transfused in either 30 or 60 min was evaluated (3.3-26.6 ml·kg-1 ·hr-1 ). Pulmonary capillary pressure was measured as left ventricular end-diastolic pressure (LVEDP). Cardiac stress biomarkers atrial natriuretic-peptide (ANP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured 1-h post-transfusion.

RESULTS

Thirty animals were included (n = 5 per group). Transfusion of RBCs increased LVEDP in a volume-dependent manner (ΔLVEDP [mmHg]: -0.95, +0.50, +6.26, p < 0.001). Fast transfusion increased overall ΔLVEDP by +3.5 mmHg and up to +11.8 mmHg in the four units' group (p = 0.016). Doubling transfusion speed increased ΔLVEDP more than doubling volume in the larger volume groups. No difference in ANP or NT-proBNP were seen in high transfusion volume or groups.

CONCLUSION

Transfusion volume dose-dependently increased LVEDP, with speed of transfusion rapidly elevating LVEDP at higher transfusion volumes. ANP and NT-proBNP were not impacted by transfusion volume or speed in this model. TACO is seen as purely volume overload, however, this study emphasizes that limiting transfusion speed, as a modifiable risk factor, might aid in preventing TACO.