Non-White Race/Ethnicity and Female Sex Are Associated with Increased Allogeneic Red Blood Cell Transfusion in Cardiac Surgery Patients: 2007-2018.

Non-White Race/Ethnicity and Female Sex Are Associated with Increased Allogeneic Red Blood Cell Transfusion in Cardiac Surgery Patients: 2007-2018.

Authors: Sinead O’Shaughnessy, MD, MSc, Virginia Tangel, MA, MSc, Safiya Dzotsi, BA, Silis Jiang, PhD, Robert White, MD, MS, Marguerite Hoyler, MD

J Cardiothorac Vasc Anesth. 2022 Jul;36(7):1908-1918.

Commentary by:

Destiny F. Chau MD*, Faith Ross MD**, Jamie Sinton MD*** 

*Arkansas Children’s Hospital/ University of Arkansas for Medical Sciences, Little Rock, AR,

**Seattle Children’s Hospital, Seattle, WA,

***Cincinnati Children’s Hospital, Cincinnati, OH

Take-home points

  • What is already known:
  • Allogeneic blood transfusion is associated with increased morbidity and mortality.
  • Women and racial/ethnic minorities have worse outcomes in many aspects of medical care including heart surgery.
  • Women have higher rates of blood loss and transfusion during cardiac surgery.
  • What this study adds:
  • Non-White adult patients undergoing coronary artery bypass grafting and or valve repair/replacement were more likely to receive allogeneic red blood cell transfusion than White patients.
  • Women were more likely to receive allogeneic PRBC transfusion than men.
  • Non-White women had double the rate of allogeneic blood transfusion compared to White men.

Evidence of health care disparities based on race, ethnicity, and sex are disturbingly commonplace and continue to complicate medical care in the United States. This study by O’Shaughnessy et al1 brings into focus patient blood management as an area of racial and sex disparity in perioperative healthcare.  Racial, ethnic, and gender disparities have been demonstrated in nearly all aspects of medicine including adult and pediatric heart surgery.2-6 The cause of these disparities is multifactorial, involving behavioral, environmental, sociocultural, and systemic medical factors. As physicians, many of these factors are outside of our control, but it is important that we closely evaluate the ways in which the care that we provide may be subject to racial and gender bias. For example, there is evidence that Black and “Other” race children are more likely to experience failure-to-rescue, i.e., inpatient mortality after complications of congenital heart surgery,7 and more likely to die without being offered mechanical circulatory support.8 Black children awaiting heart transplants have higher waitlist mortality than White patients and have shorter graft survival and increased odds of graft failure.6,9

Both adult and pediatric patients are at high risk for requiring blood transfusion during heart surgery. The use of allogenic blood products has been associated with a variety of complications including transfusion reactions, renal failure, infection, longer length of stay, and possibly mortality.10-12 Many programs have adopted strategies for patient blood management that focus on minimizing the need for allogenic transfusion. Disparities in patient blood management are a potential source of bias that may contribute to the observed racial and gender outcome differences.

Summary of Study

The authors of this retrospective observational study aimed to evaluate disparities in the transfusion of allogeneic and autologous red blood cell products in cardiac surgery along White and non-White (Black, Hispanic, and others), and sex (female vs. male) cohorts.  They analyzed data from 2007 to 2018 obtained from the State Inpatient Databases of FL, MD, KY, WA, NY, and CA including 710,296 adult inpatients undergoing elective or emergency coronary artery bypass grafting (CABG), cardiac valve surgery, or a combination of both.

The primary outcome was the percentage of patients receiving allogeneic RBC transfusion and autologous transfusion, each as referenced to those receiving no transfusion.  Secondary outcomes included in-hospital mortality, 30-day readmission, and 90-day readmission and length of stay (LOS). Additionally, the interacting effect of race and sex was studied.

Overall, 64% of patients did not receive RBC transfusion. After controlling for confounding variables (patient demographics and comorbidities, and hospital characteristics), non-White patients had approximately 20% higher odds than White patients of receiving allogeneic RBC transfusions during cardiac surgery (Black: aOR 1.17, 99% CI 1.13-1.20, Hispanic: aOR 1.22, 99% CI 1.19-1.22, Other: aOR 1.19, 99% CI 1.16-1.22, reference: White). In addition, women had 70% higher odds of receiving an allogeneic RBC transfusion than men (aOR 1.69, 99% CI 1.66-1.72). These differences held after excluding patients with a preoperative diagnosis of anemia.  Interaction modeling showed that non-White women had double the likelihood of receiving allogeneic RBC transfusion as compared to White men (Black women: aOR 2.04, 99% CI 1.91-2.17, Hispanic women: aOR 2.03, 99% CI 1.90-2.16). Overall, patients receiving allogeneic RBC transfusion had 40% higher odds of dying in the hospital (aOR 1.38, 99% CI 1.33-1.44) compared with the patients who did not receive any RBC transfusion.

A significant geographic variation was noted in the utilization of autologous blood. Its use also demonstrated significant variation by race and sex. Autologous transfusion was utilized less in non-Whites than in White patients (Black: aOR 0.78, 99% CI 0.73-0.84; Hispanic: aOR 0.93, 99% CI 0.88-0.98, other: aOR 0.79, 99% CI 0.75-0.84, reference: White). It was more likely to be utilized for females than for males (aOR 1.17, 99% CI 1.13-1.21). Additionally, autologous transfusion was associated with a reduced likelihood of in-hospital mortality and shorter hospital LOS, and showed a mitigating effect on patients receiving both autologous and allogeneic RBC transfusions.

In conclusion, the results demonstrated racial/ethnic and sex disparities in the utilization of allogeneic and autologous RBC transfusion during cardiac surgery. Non-White and female patients were more likely to receive allogenic transfusion with non-White women having twice the likelihood of receiving allogeneic RBC transfusion as compared to White men.


The purpose of red cell transfusion is to improve oxygen-carrying capacity. The literature increasingly denounces the non-infectious hazards of allogeneic blood transfusion, and the evidence is largely in favor of restrictive transfusion thresholds and patient blood management. The above factors coupled with the shortage of blood donations have contributed to the decreasing use of allogeneic blood utilization over time, a trend which is observed in this study.  Nonetheless, there is inertia to adopting evidence-based recommendations in the bedside clinical setting. Individual or institutional preferences and implicit bias regarding blood product utilization appear to be more powerful factors than professional guidelines and evidence-based recommendations.

Potential sources of provider bias and clinical decisions that may contribute to the disparities found in the study include: the minority patient not being offered the same standard of evaluation or treatment options as the White patient, the clinician’s bias unconsciously affecting decision-making and patient-physician collaboration, the effect of prior health care disparities’ impact on the patient’s preoperative condition, and lack of clinician’s specific knowledge on patient blood management. Understanding those biases on transfusion decisions and barriers to adopting patient blood management techniques such as autologous transfusion methods, e.g., normovolemic hemodilution, and perfusion monitoring technology for guiding decision-making should be further investigated. 

Limitations of this study center around the data entry reliability inherent to administrative databases and the lack of granularity such as the factors surrounding the clinical decision for allogeneic transfusion. Although comorbidities were accounted for in the study, it used the Elixhauser Comorbidity Index in which each comorbidity category is either present or it is not. Given other healthcare challenges faced by minorities and women, it is possible that the severity of comorbidities contributed to a rational decision to transfuse. Non-White patients and women may have entered the operating room with a worse ASA physical status or clinical severity than white males though this is a less likely contributor. Updates on patient blood management occurred throughout the study period. The authors mention the reduction in overall transfusion during the study period. The extent to which this reduction reaches and impacts each demographic group is unclear and deserves further study.


This article provides an important insight into disparities regarding red cell transfusion in adult cardiac surgery patients. The results agree with other studies demonstrating red cell transfusion and healthcare disparities in minority and female patient subgroups. Based on these findings, future studies should be expanded to include additional patient populations and include more granular information on provider and equipment bias, patient clinical condition, patient blood management, and transfusion protocols.

Replication of this study in adults and children undergoing surgery for congenital heart disease would provide additional information of relevance to pediatric cardiac anesthesiologists.


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