Serious hazards of transfusion initiative: analysis of the first two annual reports

British Medical Journal, July 3, 1999 by L M Williamson, S Lowe, E M Love, H Cohen, K Soldan, D B L McClelland, P Skacel, J A J Barbara

Abstract

Objective To receive and collate reports of death or major complications of transfusion of blood or components.

Design Haematologists were invited confidentially to report deaths and major complications after blood transfusion during October 1996 to September 1998.

Setting Hospitals in United Kingdom and Ireland.

Subjects Patients who died or experienced serious complications, as defined below, associated with transfusion of red cells, platelets, fresh frozen plasma, or cryoprecipitate.

Main outcome measures Death, "wrong" blood transfused to patient, acute and delayed transfusion reactions, transfusion related acute lung injury, transfusion associated graft versus host disease, post-transfusion purpura, and infection transmitted by transfusion. Circumstances relating to these cases and relative frequency of complications.

Results Over 24 months, 366 cases were reported, of which 191 (52%) were "wrong blood to patient" episodes. Analysis of these revealed multiple errors of identification, often beginning when blood was collected from the blood bank. There were 22 deaths from all causes, inducing three from ABO incompatibility. There were 12 infections: four bacterial (one fatal), seven viral, and one fatal case of malaria. During the second 12 months, 164/424 hospitals (39%) submitted a "nil to report" return.

Conclusions Transfusion is now extremely safe, but vigilance is needed to ensure correct identification of blood and patient. Staff education should include awareness of ABO incompatibility and bacterial contamination as causes of life threatening reactions to blood.

Introduction

The current incidence of major complications due to blood transfusion is unknown. Until 1996 blood transfusion was not covered by either a confidential inquiry or the yellow card system of the Committee of Safety of Medicines. Perception of transfusion safety focuses on the diminishing risk of viral transmission, while the risk of ABO incompatible transfusion due to errors in blood or patient identification remains a threat.[1 2] To analyse the residual risks of transfusion, a confidential voluntary reporting system for major transfusion events--serious hazards of transfusion (SHOT)--affiliated to the Royal College of Pathologists was launched in 1996. We have summarised the main findings from its first two annual reports.

Methods for case ascertainment

In November 1996 haematologists in the United Kingdom and Ireland were invited on a voluntary confidential basis to inform SHOT of deaths and major adverse events in seven categories (see results) associated with the transfusion of red cells, platelets, fresh frozen plasma, or cryoprecipitate. The SHOT launch was publicised at professional conferences and by an editorial in the BMJ.[3] Suspected cases of post-transfusion infection were reported to local blood centres, and cases confirmed after donor investigation as related to transfusion were collated by the National Blood Authority/Public Health Laboratory Service Communicable Disease Surveillance Centre.

Incidents other than infections reported to the SHOT office were analysed with a questionnaire then entered on a secure database without identifiers. During the second year hospitals could submit a "nil to report" return card. We have analysed data relating to incidents that occurred between 1 October 1996 and 30 September 1998.

Results

Overview

Of 424 eligible hospitals, 94 submitted 169 reports during the first year, with 112 hospitals submitting 197 reports during the second year, an increase of 16.5%. "Nil to report" cards, introduced in the second year, were submitted by 164 hospitals (39%), bringing overall participation to 65%. Reports included 191 incidents of incorrect blood transfused and 12 infections transmitted by transfusion (figure). Of 341 analysed cases, there were 22 deaths and 81 cases of major morbidity, with at least one death in every category (table).

[Figure ILLUSTRATION OMITTED]

Morbidity and mortality related to transfusions in fully analysed cases (n=341)

                                          Incorrect
                                          component
Detail                            Total   transfused

Death attributed to transfusion     22         3
Major morbidity(*)                  84        32[dagger]
Minor/no morbidity                 235       141
Total                              341       176

                                  Major acute    Major delayed
                                  transfusion    transfusion
Detail                             reaction       reaction

Death attributed to transfusion       1              3
Major morbidity(*)                    2             16
Minor/no morbidity                   47             31
Total                                50             50

Detail                               Post-
                                  transfusion   Graft versus
                                   reaction     host disease

Death attributed to transfusion       1             8
Major morbidity(*)                    5             0
Minor/no morbidity                    16            0
Total                                 22            8

                                   Transfusion    Transfusion
                                  related acute   transmitted
Detail                             lung injury    infections

Death attributed to transfusion        4              2
Major morbidity(*)                    19             10
Minor/no morbidity                     0              0
Total                                 23             12