Transfusion and transplantation-related adverse events: Transfusion injuries

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Transfusion Transmitted Injuries Surveillance System (TTISS) project

Transfusion Transmitted Injuries surveillance system (TTISS) collects data on adverse transfusion reaction (ATRs) reported during or after the transfusions of blood components (e.g., red blood cells (RBCs), granulocytes, platelets, plasma, and cryoprecipitate) and blood products/plasma derivatives (e.g., albumin, immune globulin (IG), coagulation factors, etc.) to estimate risks and trends to help improve patient safety in Canadian hospitals. As of 2007, all provinces and territories (P/Ts) with the exception of Nunavut provide data to TTISS. ATRs are voluntarily reportable to TTISS by a national network of hospitals providing transfusion services across all P/Ts except Nunavut. The TTISS network monitors over 95% of total blood transfusion activities in Canada.

The range of ATRs reported include transfusion-associated circulatory overload (TACO), intravenous immune globulin headache/haemolysis (IVIG-HD), severe anaphylactic/anaphylactoid reaction (SAAR), Transfusion-associated dyspnea (TAD), Hypotensive reaction (HYPT), acute/delayed haemolytic reaction (AHR/DHR), transfusion-related acute injury (TRALI), aseptic meningitis (ASPT), bacterial infection (BACT), incompatible transfusion (INCMPT), Viral infection (VIRINF), Post partum purpura (PTP) and unusual reactions of clinical significance (OTHERS).

The objective of TTISS is to identify and estimate risks and trends of ATRs following transfusions to help improve patient safety in Canadian hospitals.

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Key findings

About these data tiles

A total of 683 blood recipients of all P/Ts (excluding QC) hospitals in the TTISS network, resulted in adverse transfusion reactions (ATRs).

• Tile 3: 66.6% (n=455/683) were related to blood components
• Tile 4: 33.4% (n=228/683) were caused by plasma derivatives
• Tile 5: 12.6% (n=86/683) of the ATRs were definitely and 87.4% (n=597/683) were probably or possible related to transfusion
• Overall, one third 32.7% (223/683) of ATRs were reported TACO followed by IVIG-HD (13.6%, 93/683). SAAR and TAD representing (9.8%, 67/683) and (9.2%, 63/683) respectively (Fig 1)
• Tile 7: 5.0% (n=34/683) of the ATRs resulted in grade 3 (life threatening injuries) (Fig 2)
• Tile 8: 0.7% (n=5/683) of the ATRs resulted in transfusion related deaths-3 deaths were due to TRALI and 2 were due to TAD (Fig 3)
• Tile 9: 6 deaths reported per million units of blood components transfused

The TTISS findings reflect trends and outcomes consistent with those observed in other developed countries.

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Results

Notes

ATRs with few cases are not shown here, i.e.:

• Aseptic Meningitis (ASPT) (1.3%)
• Bacterial Infection (BACT) (1.2%)
• Viral Infection (VIRINF) (0.3%)
• (Incompatible transfusion) INCMPT (0.3%)
• Postpartum Purpura (PTP) (0.1%)
• Unknown (UK) (1.8%)

ATR and death rate per million units of blood components transfused

About these data tiles

The changes over time in the number of deaths should be interpreted with caution given the small number of cases reported and inherent variations in annual reporting.

Conclusion

The proportion of ATR types are consistent from previous years. Additionally, while TACO and TAD are the leading causes of death; the overall fatality risk in comparison to the total number of transfusions remains low in Canada.

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Related resources

• Transfusion Transmitted Injuries Surveillance System, 2022: Infographic
• Transfusion Transmitted Injuries Surveillance System, 2020 to 2021: Infographic
• Transfusion Transmitted Injuries Surveillance System Summary Report, 2016 to 2020

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