Vol. 21 • Issue 10 • Page 20
Transfusion Medicine
A variety of complications and adverse events – infectious and non-infectious – can be encountered as the result of transfused blood components. While infectious transfusions (which run the risk of contaminating patients with diseases like HIV) have decreased significantly, non-infectious transfusion reactions have become the most common complications of transfusions, ranging from categorized transfusion reactions to lesser known complications.1
The signs and symptoms can be common across a variety of adverse events, making it difficult to discriminate clinically between impending severe reactions and minor reactions. Transfusion of incompatible blood has the greatest potential for severe adverse events and health complications, including death. Fortunately, due to advances in transfusion medicine (TM) practices – improved blood testing, donor screening and the advent of automated systems – the blood transfused to patients is safer today than it’s ever been. However, awareness of the types of reactions that occur, their symptoms and education about ways to alleviate the potential for error can help avoid these reactions and further decrease associated fatalities.
Understanding Transfusion Reactions
Non-infectious transfusion reaction severity can vary from minor to serious, with reactions typically presenting adverse signs or symptoms during or within 24 hours of a blood transfusion.2 When they occur, transfusion reactions require immediate recognition, laboratory investigation and clinical management. Because they may present themselves in complex clinical situations, the diagnosis requires distinguishing between a reaction to the transfused blood product and a coincidental complication of the underlying illness being treated with the transfusion.2
Some of the more common, often serious, immediate transfusion reactions are classified as follows:2-4
• Transfusion-related acute lung injury (TRALI): Acute lung injury (ALI) that occurs during or within six hours of a completed transfusion, often due to the presence of antibodies in the donor plasma or the production of inflammatory mediators during storage of cellular blood components
• Acute hemolytic reactions: Interaction of transfused red blood cells with pre-formed antibodies in recipient, often due to human error such as mislabeled pre-transfusion specimen, the transfusion of properly labeled blood to the incorrect patient, laboratory testing error or clerical errors
• Transfusion associated sepsis: Bacterial contamination of transfused blood or components that enter during collection or processing
Frequency of Transfusion Fatalities
While reduced dramatically in recent years, transfusion reactions and fatalities do occur and when this happens, laboratories are required to report them directly to regulatory agencies. From Oct. 1, 2010, through Sept. 30, 2011, the FDA received a total of 79 fatality reports. Of these, 69 were determined to be transfusion recipient fatalities and 10 were deemed post-donation fatalities.5 Of the 69 transfusion recipient fatality reports, the FDA concluded:
• 43% were transfusion-related
• 41% were cases in which transfusion could not be ruled out as the cause of the fatality
• 16% were unrelated to the transfusion5
According to the FDA, TRALI was the leading cause of reported transfusion fatalities in recent years (43%), followed by acute hemolytic transfusion reactions (23%). Both of these reactions typically occur due to human error. Complications of transfusion-associated circulatory overload (TACO), microbial infection and anaphylactic reactions each accounted for a smaller number of the reported fatalities.5
The number of transfusion-related fatalities reported to regulatory agencies remains small in comparison to the total number of transfusions; however, these events account for more than $17 billion in added costs in the U.S. alone.6 These added charges can exceed the initial transfusion acquisition and procedure costs combined, further burdening a fragile healthcare system. Additionally, reactions due to human error are often misdiagnosed or underreported, thereby potentially increasing the number of transfusion related events on an annual basis.7
Data appears to support the notion that missed or underreported transfusion-related reactions and fatalities are likely a global consideration. For example, in 2008 the Blood Bank Unit of Universiti Kebangsaan Malaysia Medical Centre (UKMMC) conducted a retrospective study based on data that was secured from the laboratory’s information system. A total of 27,842 transfusions were documented with 149 reported transfusion reactions.8 While it is difficult to effectively compare data on a global basis, the UKMMC data indicates that the number of reactions at this international center was nearly three times the number of deaths reported to the FDA in the same year.8 As errors and “near misses” can quickly lead to fatalities, it’s important to consider the impact of transfusion reactions globally as well.
While the number of adverse events remains a small portion of the total number of transfusions, the underreporting of these incidents and the possibility that they can be fatal underscores the need to eliminate the human error that contributes to transfusion reactions around the world.
Critical Control Points
The establishment of critical control points along the bloodline from donor to patient is essential to the practice of safe blood transfusion – delivering the right blood to the right patient at the right time for the right reasons. The process starts with the evaluation of a patient’s need for blood products and an accurate sample collection from the correct patients, followed by pre-transfusion testing, blood product selection and issuance, and the administration of the blood product(s). The process is not complete until the patient is re-evaluated to ensure an appropriate outcome of the blood transfusion.9
Assessing blood products at critical junctions in the transfusion process – from testing to labeling to storing and retrieving and transporting components – is necessary to manage the possibility of human error along the way. The process begins with testing the safety of donor blood and transitions to the responsibility of the TM laboratory to ensure appropriately labeled blood was received. When pre-transfusion testing begins, it is critical that the process steps have the lowest error potential as possible.9 Recipient blood must be evaluated effectively with appropriate testing procedures prior to the transfusion occurring. At the point of care, healthcare professionals must be educated and aware of patient identity and symptoms of reactions and must constantly monitor patients to be assured that reactions are not occurring.
Using Automation Technology, Education
Human error is the most common cause of transfusion reactions and related mortality. While pre-transfusion testing is only one part of the overall procedure, new technologies, including column agglutination (CAT) and automated platforms, and even barcoding procedures, have been created in recent years to significantly improve safety and efficiencies.9 Today’s primary pre-transfusion testing methods include:9
• Traditional test tube methods
• Large-well titration plate (tiles) methods
• Manual CAT for ABO/D and antibody screening
• Automation using RBC agglutination for ABO/D in microplate based technology and solid-phase RBC adherence for antibody screening (Galileo, Galileo ECHO and Galileo NEO – Immucor)
• Automation using CAT (ID-GelStation-DiaMed or ORTHO ProVue®, Ortho Clinical Diagnostics; and ORTHO AutoVue® Innova, Ortho Clinical Diagnostics)
Despite the well-documented benefits of automation, the majority of blood donor centers and transfusion services around the world continue to use manual methods for routine ABO/D blood group determinations and unexpected antibody screening tests (G&S). Based on supporting evidence, it seems reasonable to suggest that most of the G&S and other ancillary testing human errors identified could be eliminated with pre-transfusion test automation.
A study conducted by Ortho Clinical Diagnostics provides quantitative evidence of how automation could transform pre-transfusion testing processes by dramatically reducing error potentials and thereby improve the safety of blood transfusion.9 Evaluating the common testing methods above and leveraging failure modes and effects analysis (FMEA) to compare error potentials, the group concluded that automation significantly reduces defect opportunities in pre-transfusion testing and could dramatically improve blood transfusion safety.
Finally, ongoing education is important to bring understanding and adoption of improved techniques to blood bank professionals. In today’s world, increased time demands and reduced resources for ongoing training make it difficult for blood bankers to update their knowledge and skills.
Transfusion Medicine: The Goal
The critical goal for blood bank professionals is to reduce pre-transfusion testing errors to zero to contribute to the overall safety of blood transfusions. Small human errors can take place anywhere along the journey from vein-to-vein, and technology innovations to manage risk continue to advance to make transfusions safer.
While some transfusion medicine factors will remain beyond our control, the vast majority can be understood with issues management procedures in place. Implementing systems that reduce preventable errors is the best way to manage that risk and ultimately protect patients.
Tony Casina is with Transfusion Medicine Marketing, Ortho-Clinical Diagnostics, Inc.
References
1. Hendrickson JE, Hillyer CD. Noninfectious Serious Hazards of Transfusion. Anesth Analg. 2009;108:759 -69.
2. Transfusion Reactions. http://emedicine.medscape.com/article/206885-overview. Accessed August 8, 2012.
3. 7 Adverse Reactions to Transfusion. http://www.pathology.med.umich.edu/bloodbank/manual/bbch_7/index.html. Accessed August 8, 2012.
4. Adverse Transfusion Reactions. United Blood Services for Hospitals and Physicians. http://hospitals.unitedbloodservices.org/adverse-reactions.html. Accessed August 8, 2012.
5. Food and Drug Administration (FDA). (2011). Fatalities Reported to FDA Following Blood Collection and Transfusion. Washington, DC: Government Printing Office.
6. Shander A, Hofmann A, Gombotz H, Theusinger OM, Spahn DR. Estimating the cost of blood: past, present, and future directions. Best Pract Res Clin Anaesthesiol. 2007;21:271-89.
7. Williams, L. (2011). The TSO’s Role in Hemovigilance and Patient Blood Management. AABB News.
8. Leong CF, Rabeya Y, Abdul-Kahar AH. An audit of reported acute transfusion reactions in Universiti Kebangsaan Malaysia Medical Centre. Malaysian J Pathol. 2011;33(1):25-29.
9. Sount S, Casina T, Li L. Exponential error reduction in pretransfusion testing with automation. Transfusion. 2012;52:81-88.
