The Serious Hazards of Transfusion (SHOT) scheme collects and analyses anonymised information relating to serious adverse reactions (SAR) and serious adverse events (SAE) of blood transfusion reported in the United Kingdom (UK). From this data, SHOT makes recommendations to improve patient and transfusion safety. A breakdown of the 2022 Annual SHOT Report1 (assessing a total of 3499 case reports) is shown in Figure 1.
In total, 2908/3499 (83.1%) reports were errors, which continue to account for over 80% of reports submitted each year. Learning from these incidents allow SHOT to identify trends in transfusion safety, develop educational resources and issue recommendations for safer practice. The proportion of errors year on year remains consistent, and taking a holistic approach may help to reduce these. To understand the source of transfusion errors, investigations should look further than the individual, and a system-based approach should be employed
Key SHOT messages
Safe staffing: Clinical and laboratory teams can function optimally only if they are adequately staffed and well resourced. Staffing challenges in both clinical and laboratory areas are commonly cited as contributory in transfusion incidents and must be addressed urgently. Adequate numbers of appropriately trained staff must be available to ensure safe transfusions; there should be contingency planning for staffing levels below a minimum level and for times of high workload.
Well-resourced systems: Healthcare leaders and management must ensure that staff have access to the correct information technology (IT) equipment which is fit for purpose. Adequate financial resources are a must for safe and effective functioning of teams.
Addressing knowledge gaps, cognitive biases, and holistic training: Providing transfusion training with a thorough and relevant knowledge base in transfusion to all clinical and laboratory staff along with training in patient safety principles, understanding human factors and quality improvement approaches is essential. It is important that staff understand how cognitive biases contribute to poor decision making so that these can be mitigated appropriately
Patient safety culture: Fostering a strong and effective safety culture that is ‘just and learning’ is vital to ensure a reduction in transfusion incidents and errors, thus directly improving patient safety.
Addressing transfusion delays: Avoidable transfusion delays continue to contribute to patient deaths and measures recommended in the SHOT CAS alert2 must be implemented to address these.
Addressing transfusion errors: Errors continue to be the source of most SHOT reports (83.1%). While transfusions are largely safe, errors can result in patient harm. Many of these are caused by poor communication and distraction. These must be investigatedusing human factors, principles-based incident investigations and appropriate mitigating measures implemented.
Learning from near misses: Reporting and investigating near misses helps identify and control risks before actual harm occurs, providing valuable opportunities to improve transfusion safety.
Shared care: Clear, timely and comprehensive communication between all teams and hospitals involved in patient care is vital in ensuring patient safety. Robust and transparent processes must be in place for safe and effective transfer of information at all points in the patient-care pathway
The 2022 Annual SHOT Report has four main recommendations:
1. Appropriate management of anaemia with effective patient blood management and safe transfusion decisions are vital to improve safety.
2. Well-resourced systems, with adequate numbers of trained staff supported by technology and automation help ensure safe transfusions.
3. System-focused interventions to address gaps identified during incident investigations must be implemented for a sustained improvement.
4. Learning from excellence and day-to-day events will support a proactive approach to safety.
Deaths, major morbidity and ABO–incompatible transfusions
In 2022, there were 35 deaths related to transfusion (identical to 2021), of which three were definitely due to the transfusion (imputability 3), see Figure 2. The SHOT figures for 2022 translate to a risk of death in the UK of 1 in 63,563 (1.57 per 100,000) components issued and the risk of serious harm is 1 in 15,449 (6.47 per 100,000) components issued.
For the first time, delays in transfusion contributed to the highest number of deaths, 13/35 (37.1%), with transfusion-associated circulatory overload (TACO) contributing to 8/35 deaths (22.9%) as shown in Figure 3. Of note, there were two deaths following inadvertent ABO-incompatible (ABOi) red cell transfusions, both of which were totally preventable.
A total of six ABOi events were reported in 2022, of which five were ABOi red cell transfusions (all due to clinical errors). These errors resulted in two patient deaths; in both cases the primary error was at component collection. There was one case of major morbidity following an ABOi due to an administration error.
There was one ABOi transfusion of fresh frozen plasma (FFP) due to a laboratory error at component selection. A further 19 potential ABOi transfusions were avoided because errors were detected prior to transfusion. Figure 4 shows a summary of potential outcomes resulting from ABO-compatibility errors in the transfusion pathway
Most ABOi errors were compounded by a lack of reliable, accurate patient identification, plus the influence of staffing issues with suboptimal skill mix, high workload, knowledge gaps, decision fatigue and assumption bias.
Serious adverse reactions
Serious adverse reactions were reported in a total of 571 cases. As in previous years, febrile, allergic and hypotensive reactions (FAHR) remain the most commonly reported reactions 294/558 (52.7%). When laboratory investigations are requested for suspected FAHR, these should be tailored to the reaction type and if severe enough for transfusion to be discontinued, repeat compatibility testing should be performed (except in cases with purely allergic features).
Laboratory and clinical staff should have clear lines of communication in suspected reactions to allow for all feasible causes to be investigated without introducing unnecessary delay or resource use. Updated guidance on the investigation and treatment of acute transfusion reactions has been published by the British Society for Haematology in 2023, and should be used to guide decision making.3
FAHR reactions are unpredictable and largely unpreventable, illustrating the importance of giving transfusion only when there is no suitable alternative. Transfusion decisions must be made after considering risks and benefits to patients. Where transfusions are concerned, less is often more. In 11 cases, the reporter deemed that transfusion was not clinically indicated according to the relevant BSH guidelines. In a further 28 cases this was ‘unknown’ and in another seven cases, not stated.
There was one death possibly related to transfusion. A patient with relapsed leukaemia suffered an allergic reaction during a platelet transfusion, followed by airway obstruction requiring intubation and cardiac arrest. Prior to the transfusion the patient was gravely unwell, being managed in the intensive care unit and had recently received emergency chemotherapy. Various factors may have contributed to the acute deterioration and outcome in this patient.
While most are minor, anaphylaxis can be life-threatening, and this emphasises the need to ensure that transfusion is only given when clinically indicated and there is fully informed patient consent. Suboptimal management of acute transfusion reactions continue to be reported, particularly the inappropriate use of antihistamine and/or steroids to treat febrile reactions (in 46.9% of cases).
There is a lack of selectivity in investigations following the event, with compatibility testing frequently performed unnecessarily following allergic reactions. The key message remains the need to use the patient’s symptoms and signs to distinguish febrile from allergic reactions and to tailor investigation and management accordingly
An antihistamine with or without steroid continues to be used inappropriately to treat reactions with only febrile/inflammatory type symptoms and/or signs. In addition to no evidence of benefit, the repeated use of steroids may further immunosuppress already immunocompromised patients and increase the risk of side effects such as infection.
Laboratory investigations should be tailored to the reaction type. If a febrile reaction is sufficiently severe to warrant discontinuing transfusion completely, compatibility testing should be repeated. Repeat compatibility testing is not required in reactions with purely allergic features.3
Transfusion was discontinued completely in 95/132 (72.0%) febrile reactions. In 22 of these, there was no mention of repeat compatibility testing.
Of the 117 reactions with purely allergic features, 47/117 (40.2%) were unnecessarily investigated with repeat compatibility testing and in 29 blood cultures were taken from the patient.
Anti-D Immunoglobulin (Ig) errors
In 2022, there were 345 cases related to errors in anti-D Ig management during pregnancy, and the impact of anti-D Ig and routine ante-natal anti-D prophylaxis (RAADP) errors should not be underestimated.
Omission or late administration of anti-D Ig or RAADP accounted for 232/345 (67.2%) cases analysed, of which 51/232 (22.0%) related to patient discharge prior to administration with 26/232 (11.2%) caused by flawed decisionmaking.
Administration to a mother carrying a D-negative infant accounted for 34/345 (9.9%) cases, nine due to failure to check cell-free fetal DNA (cffDNA) or cord blood D-types and 11 due to false positive D-types predicted by cffDNA screening.
Anti-D Ig was administered to mothers with immune anti-D in 22/345 (6.4%) cases, eight resulted from failures to check records.
D-positive mothers received anti-D Ig inappropriately in 19/345 (5.5%) cases, seven of these were weak D-types, other errors included failure to check results and transcription errors.
There were 13/345 (3.8%) cases that involved administration of incorrect doses, five of these related to failure to perform Kleihauer testing, cases of under-dosing related to cell salvage and miscalculation of FMH, over-dosing resulting from miscalculation of FMH and challenges around appropriate administration following frequent potentially sensitising events (PSE).
Anti-D Ig was administered to the wrong woman in 12/345 (3.5%) cases, all resulted from failures in PPID.
Errors in the handling and storage of anti-D Ig accounted for six cases, two of which were administration of expired products, two storage errors and two administered without prescription.
Finally, three cases were classified as miscellaneous, and four Right Product Right Patient cases related to errors in labelling of anti-D Ig.
SHOT data continue to demonstrate that errors in anti-D Ig and RAADP management occur in both clinical and laboratory settings. The management of anti-D Ig and RAADP is multifaceted, errors occur at all stages of the process, from the identification of the requirement, ordering, prescription, laboratory issue, storage and administration. The implementation of non-invasive cffDNA screening has undoubtedly improved practice by targeting administration of this blood product to those who need it, both reducing unnecessary exposure to mothers carrying D-negative fetuses and protecting supplies of the product.
Wrong Blood in Tube (WBIT)
WBIT samples continue to be a problem with a large increase in reports in 2022 (n=890) compared to 2021 (n=734). Cases from maternity departments make up 40% of the reports. WBIT errors result from two main causes: failure to identify the patient correctly at phlebotomy 353/890 (39.7%) and labelling the blood samples away from the patient 286/890 (32.1%). In 50 reports, the cause of error was not stated. In 159/890 (17.9%) cases where the cause was recorded both errors occurred together.
Mistakes can occur at the first contact with the hospital. In five cases, patients were wrongly identified at initial registration. In one case this was associated with the patient being non-English speaking. In another instance a woman was misidentified by clerical staff on admission to the emergency department (ED) because a patient with a similar name was picked from the patient information system. This mistake was detected when the blood group was found to be discrepant with the previous records of the wrong patient. These cases are another reminder that correct patient identification is vital at all times. Overall, 639/890 (71.8%) were attributed to failure to identify the patient at the time of sampling or the sample was not labelled at the bedside.
There were seven cases of mix-ups between maternal and cord blood samples, and two cases where an agency staff nurse (who had not received transfusion training) took samples from multiple patients and labelled them later away from the bedside ‘to save time’. Most errors were detected by laboratory staff, 717/890 (80.6%) during testing or at authorisation of results. In 689 cases blood group data were provided. If these WBIT had not been detected, 320/689 (46.4%) could have received ABOi components with a risk of serious harm or death. NM-WBIT events are caused by the same two errors identified regularly in SHOT reporting for the past 25 years, namely failure to identify the patient correctly at the time of phlebotomy and failure to label the blood samples while next to the patient. Both these errors occurred together in a fifth of all cases. Maternity departments and clinics are high-risk areas
Suboptimal practice is shown to continue, and the systemic reasons behind this should be explored to improve patient safety. Near miss events should be monitored and investigated using human factors principles. In 2012, the British Committee for Standards in Haematology (BCSH, now BSH) guidelines recommended that any patient who has never been transfused should have a second group-check sample taken to reduce the risk of wrong blood transfusions.4
A recent survey of junior doctors and physician associates in ED demonstrated an alarming rate of non-compliance including 136/209 (65.1%) who reported having taken two group and antibody screen samples together and labelled them at different times.5 Better understanding of the potential risks introduced and factors contributing to normalised non-compliance is needed
Information technology (IT)
IT systems can improve patient care by removing transcription errors, linking records and storing information on patient histories among many other functions. However, these improvements are only realised when the systems are used as intended and workarounds are not employed. IT systems should be fit for purpose, they are reliant on correct setup, sufficient staff training, and ongoing system development. Staff should receive proper training when IT systems are used and maintain competence in downtime procedures when IT is not available.
Furthermore, where IT is used as a safety measure, this should not replace staff knowledge and should be there as an additional barrier. Many errors included overriding alerts, overreliance on alerts to ‘stop’ errors, alerts not updated, and issues around legacy data. Healthcare staff must understand ‘why’ as well as ‘how’ a particular procedure is required.
Alongside the 2022 Annual SHOT Report, the SHOT Collaborative Reviewing and reforming IT Processes in Transfusion (SCRIPT) launched the document ‘Using Information Technology for Safe Transfusion’ to detail how IT systems can be employed throughout the transfusion process, help when investigating transfusion incidents and when writing business cases for transfusion IT. 6
Acknowledging continuing excellence (ACE)
In 2022, a total of eight reports were received under the ACE category and showed a wide range of themes such as innovation, communication and collaboration, and patient focus. Learning from excellence provides the opportunity to celebrate the hard work of healthcare staff and improves safety outcomes for patients. These should be shared widely to enable other departments and organisations to benefit.
There is also great benefit to learning from everyday work, as this is less resource intensive, does not require the presence of adverse events and can improve team morale by involving and valuing everyone’s opinion. It also provides a holistic approach to safety, combining Safety-II along with Safety-I. There are many ways to incorporate ACE into routine procedures, some of which are shown in Figure 5.
Systems thinking and human factors in process design
Systems for healthcare delivery should be present which all healthcare professionals and patients can rely upon. However, transfusion errors reported to SHOT are often caused by faulty systems, processes, and conditions that lead people to make mistakes, therefore these are the areas to be focused upon when seeking to reduce errors and increase excellence. If we consider these factors when designing systems and put the people at the heart of the process, the processes should naturally perform in a way which is beneficial to its users. These interventions require the support from senior management and healthcare leaders. Figure 6 shows the many different factors to consider when designing systems for safe transfusion.
Conclusions
A systems-thinking approach is beneficial when forming corrective and preventive actions to improve transfusion safety. This should include learning from adverse events, everyday occurrences, and excellence. Where there are areas of interest and improvement within organisations, a tool such as the SHOT driver diagram7 may be useful to help identify the many systems which feed into this.
This can be used to direct investigations to the right pressure points and may uncover potential solutions. The SHOT driver diagram to help identify tactical change ideas to enhance transfusion safety is aimed at the outcomes of the 2022 Annual SHOT Report; however, the concept may be useful within individual organisations.
The 2022 Annual SHOT Report shows that there are improvements to be made in transfusion safety, and that the solutions to these are wider than the individual. The report also shows that those working in healthcare are imaginative, hardworking, and caring individuals who seek the tools to be able to do their best. It takes all of those involved in decision making to be invested in improving systems and working conditions, to improve the safety of staff and patients.
About the authors
Victoria Tuckley is a registered Clinical Scientist and Biomedical Scientist. She has previously worked within red cell immunohaematology and stem cell immunotherapy laboratories, and expanded her motivation for improving the patient experience while working as a transfusion practitioner. She has been a laboratory incidents specialist for Serious Hazards of Transfusion for four years.
Si Carter-Graham registered as a Nurse in 1989 and has worked in Emergency Departments, Acute Medicine and Medical Assessment. Within NHS Blood and Transplant, he has worked as Area Lead Nurse for blood donation, as a Tissue Donor Co-ordinator and was the National Referral Centre Manager (Tissue & Eye Services). Si has worked as Clinical Incident Specialist in SHOT since 2018.
References
1. S Narayan (Ed), D Poles et al. on behalf of the Serious Hazards of Transfusion (SHOT) Steering Group. The 2022 Annual SHOT Report (2023). https://doi.org/10.57911/WZ85-3885.
2. Serious Hazards Of Transfusion. Central Alerting System: Preventing transfusion delays in bleeding and critically anaemic patients. MHRA 2022 (https://www.cas.mhra. gov.uk/ViewandAcknowledgment/ViewAlert. aspx?AlertID=103190)
3. British Society for Haematology. Guidelines for investigation and treatment of acute transfusion reactions. BSH 2023 (https://b-s-h.org.uk/guidelines/ guidelines/guideline-on-the-investigation-andmanagement-of-acute-transfusion-reactions)
4. BCSH Milkins C, Berryman J, Cantwell C, et al. Guidelines for pre-transfusion compatibility procedures in blood transfusion laboratoriesTransfus Med 2013;23(1):3-35. https://b-s-h.org. uk/guidelines/guidelines/pre-transfusioncompatibility-procedures-in-bloodtransfusion-laboratories
5. Cain L. and the HaemSTAR collaborators. The ‘ Two Sample Rule’ in Emergency Departments: a UK-wide survey of junior doctors/physician associates. Oral abstracts book BSH23-OR26. Br J Haematol. 2023;201:4-27. https://doi. org/10.1111/bjh.18718
6. SHOT UK Collaborative Reviewing and reforming IT Processes in Transfusion (SCRIPT). Using information technology for safe transfusion. SHOT 2023 (https://www. shotuk.org/wp-content/uploads/myimages/ SHOT_Using-Information-Technology-for-SafeTransfusion.pdf)
7. Serious Hazards Of Transfusion. Driver diagram to help identify tactical change ideas to enhance transfusion safety. SHOT 2023. (https://www. shotuk.org/wp-content/uploads/myimages/ SHOT-Driver-Diagram_ A3@100pc-Landscape_ v5.pdf