| Term | Definition | |
|---|---|---|
| DAE | Donor Adverse Event | An event where harm occurs to a donor as a result of the blood donation process. |
| SDC | Serious Donor Complication | A DAE which is graded at Grade 3 or above using the Severity Grading Tool |
| SAED | Serious Adverse Event of Donation | A DAE which meets the previous severity criteria agreed by the UK Blood Services |
A donor adverse event (DAE) which is graded as either a serious donor complication (SDC) or a serious adverse event of donation (SAED) meets the Medicines and Healthcare products Regulatory Agency (MHRA) definition of a Serious Adverse Reaction: “An unintended response in a donor or in patient associated with the collection or transfusion of blood or blood components that is fatal, life-threatening, disabling, incapacitating, or which results in, or prolongs, hospitalisation or morbidity.”
DAEs are classified according to the categories included in the Standard for Surveillance of Complications Related to Blood Donation (2014)3. In 2023/24, the UK Blood Services agreed to implement the validated donor severity grading criteria developed by the AABB Donor Haemovigilance Working Group and endorsed by ISBT, IHN and EBA4,5. This records the severity of donor adverse events by Grades 1-5, with 1 through 5 being roughly associated with mild, moderate, severe, life-threatening and death. Further details of DAE classification, grading and assignment of imputability scores are given below (see sections 5.10.3 – 5.10.5).
Management of all SDCs or SAEDs should include appropriate incident investigation to ensure that proper preventative and corrective actions are implemented. This supports optimal learning from reported incidents.
The Blood Safety and Quality Regulations (BSQR) mandate that blood establishments report serious adverse events or reactions, including those which occur in donors. Each Blood Service is therefore required to submit an annual report to the MHRA covering any DAE which are classified as SDCs. During the transition period for introduction of the Severity Grading Tool, Services may alternatively choose to report using the previous SAED categories (see 5.10.6).
Blood Services must also ensure that:
The care of all donors at blood collection venues should incorporate research-based therapeutic interventions to reduce the risk of adverse events of donation.
Blood Services are encouraged to collect all DAE data in a format which will allow analysis of DAE trends over time both within and between services (benchmarking). This will also enable monitoring of the effectiveness of any interventions to reduce event rates.
A summary of the serious donor adverse events reported in the 4 UK Blood Services is included in the donor haemovigilance chapter in each Annual SHOT Report – these can be accessed here: www.shotuk.org/shot-reports.
(based on Standard for Surveillance of Complications Related to Blood Donation3)
| Code | Description |
|---|---|
| A | Complications mainly arising from local symptoms |
| A.1 | Complications mainly characterised by the occurrence of blood outside the vessels
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| A.2 | Complications mainly characterised by pain
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| A.3 | Localised infection/inflammation |
| A.4 | Other major blood vessel injury
|
| B | Complications mainly with generalised symptoms: vasovagal reactions |
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| C | Complications related to apheresis |
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| D | Allergic reactions |
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| E | Other serious complications related to blood donation |
| Major cardiovascular event such as acute cardiac symptoms, myocardial infarction, cardiac arrest, transient ischaemic attack, cerebrovascular accident, death | |
| F | Other complications |
| Systemic reactions or complications which do not fit into any of the categories listed above |
(based on Severity Grading Tool for Blood Donor Adverse Events5)
| Severity Grade | Criteria |
|---|---|
| Grade 1 | Did not require intervention from an external Health Care Practitioner (HCP) AND Duration ≤2 weeks AND No limitation on Activities of Daily Living (ADL) AND Resolved with no or minimal intervention |
| Grade 2 | Required intervention from an external HCP, no hospitalisation OR Duration >2 weeks and ≤6 months OR Limitations on ADL ≤2 weeks |
| Grade 3 | Not life-threatening AND any of the following Hospitalisation OR Duration >6 months OR Limitations on ADL >2 weeks OR Require surgery OR Other serious complications (Category E) |
| Grade 4 | Immediate medical intervention required to prevent death |
| Grade 5 | Death |
When assessing DAEs, assign the highest applicable severity grade. The Severity Grading Tool should be referenced for guidance on specific DAE categories.
Imputability in the context of blood donation means the likelihood that a DAE can be attributed to the donation. Imputability is scored according to the criteria below based on the SHOT Definitions (2023)6.
| Score | Imputability | Definition |
|---|---|---|
| N/A | Not Assessable | When there is insufficient data for imputability assessment. |
| 0a | Excluded | When there is conclusive evidence beyond reasonable doubt for attributing the adverse reaction to causes other than the blood or blood components or where the evidence is clearly in favour of alternative causes. |
| 0b | Unlikely | |
| 1 | Possible | When the evidence is indeterminate for attributing the adverse reaction either to the blood or blood component or where there may be alternative causes. |
| 2 | Likely / Probable | When the evidence is clearly in favour of attributing the adverse reactions to the blood or blood component. |
| 3 | Certain | When there is conclusive evidence beyond reasonable doubt attributing the adverse reactions to the blood or blood component. |
Prior to implementation of the Severity Grading Tool, DAE were classified as Serious Adverse Events of Donation (SAEDs) if they fell into one of the categories listed in the table below. Mapping of SAED categories to the new classification and grading system is also shown. Note that if reporting under SAED criteria, fewer adverse events will be included.
During the transition phase for introduction of the Severity Grading Tool, services may continue to use SAED classifications for reporting of serious adverse reactions to SABRE and SHOT.
| Code | SAED Category | Mapped to Classification and Severity Grading Tool |
|---|---|---|
| 01 | Death within seven days of donation | Any category, Grade 5 |
| 02 | Hospital admission within 24 hours of donation | Any category, Grade 3 or 4 |
| 03 | Injury resulting in a fracture within 24 hours of donation (including fractured teeth) | B, Grade 3 |
| 04 | Road traffic collision within 24 hours of donations | B*, Grade 3 or 4 *If due to vasovagal reaction |
| 05a | Problems relating to needle insertion persisting for more than one year (this mainly includes suspected or confirmed nerve and tendon injuries) | A (usually A.2), Grade 3 |
| 05b | Problems relating to needle insertion requiring hospitalisation/intervention (this mainly includes vascular complications) | A (usually A.4), Grade 3 or 4 |
| 06 | Acute coronary syndrome diagnosed within 24 hours of donation | E, Grade 3 or 4 |
| 07 | Anaphylaxis (component donation) | D, Grade 3 or 4 |
| 08 | Haemolysis (component donation) | C, Grade 3 or 4 |
| 09 | Air embolism (component donation) | C, Grade 3 or 4 |
| 10 | Other event related to donation resulting in: Hospital admission, Intervention, or Disability or incapacity lasting more than one year and not included above |
F, Grade 3 or 4 |