Prevention of bacterial contamination, including initial flow diversion

Abstract

Blood centers and hospitals worldwide face a continuing challenge to improve the safety of blood components for transfusion. Important improvements have been achieved due to careful donor selection, and advances in collection, testing, storage and handling. Transfusion-transmitted infections (TTIs) are now rare in many countries. However, haemovigilance system reports reveal that bacterial contamination of blood components remains an important residual risk, particularly relating to platelet transfusions. For example, the 2008 annual report from the Serious Hazards of Transfusion (SHOT) scheme in the United Kingdom describes a total of 38 confirmed TT bacterial events since 1998 [1]. The majority (32) of these were related to platelets and the others (six) to red cells. Forty patients were affected in total, as some apheresis platelets were split and went to different recipients, with both patients suffering an adverse event. In 2008, all four confirmed cases were due to platelets, with consequences ranging from minor morbidity to death in a total of six patients. This can be contrasted with 22 confirmed TT viral or parasitic infections in 25 patients reported to SHOT since 1998, and no confirmed infections reported between 2006 and 2008. Clearly, therefore, this is an important area where ongoing efforts are warranted to improve transfusion safety. This review will focus on efforts to prevent bacterial contamination occurring, with some consideration of methods to detect it, where present, in order to prevent contaminated units reaching the patient.