Number of adverse transfusion events and reactions

Event type

Events reported 1996−2004

Events reported per 100,000 components issued 1996−2004

Events reported 2003−2004

Events reported per 100,000 components issued 2003−2004

Incorrect blood component transfused (IBCT)

1832

7

787

12

ABO incompatible transfusions (all components − included in IBCT)

249

1

56

0.8

Death as a result of IBCT

20

0.07

3

0.04

Transfusion-related acute-lung injury (TRALI)

162

0.6

59

0.9

Fatal TRALI

36

0.1

9

0.1

Acute transfusion reaction (ATR)

267

1

73

1

Transfusion-transmitted infection (including bacterial)

49

0.2

6

0.1

Total adverse reactions/events

2628

10

994

14

Total transfusion-related deaths

100

0.4

21

0.3

Notes:

• Data reported to the UK Serious Hazards of Transfusion Scheme, 1996 to 2004.
• Data from unpublished UK studies indicate that individuals who receive a red cell transfusion in any year receive an average of four or five units. However, the distribution is skewed: most recipients receive two units, while a small minority receive much larger numbers.
• The risk of experiencing an adverse event is greater in recipients of greater numbers of transfusions, but is not a simple function of the number of units received.
• Over a period of eight years, 2628 events (not including ‘near misses’) have been reported to SHOT. During the same period, 27 million blood components were issued by the UK blood services. Using these figures, and the analysis of types of events undertaken annually by SHOT, the major risks of transfusion can be crudely calculated. Not all reported adverse reactions and events are included in the table.
• The total number of blood component units issued by the blood services to hospitals is used as the denominator.
• TRALI and severe allergic reactions (counted as ATRs) are some four to six times more likely to occur in relation to plasma and platelets than to red cells.
• The table does not reflect the number of patients transfused or the number of transfusion episodes.
• The causal relationship between the observed reaction and the transfusion is often not clear cut.