What is the optimal pretransfusion testing interval for multi-transfused patients? The University Hospital of Brest experience

Abstract

The red cell allo-antibodies research is mandatory before transfusion. In France, pretransfusion testing intervals that are prescribed by regulatory and accrediting agencies are commonly 72hours. In the University hospital of Brest, the interval for multi-transfused patients has been 24hours. In this study we aim to analyse these practice and argue the delay.

Methods: This is a retrospective study of post-transfusional allo-immunizations from 2015 to 2020. For each patient, the time interval between the last negative research and the allo-immunization was investigated.

Results: 189 patients developed allo-antibodies. In 16 patients (8,5%), the interval for allo-immunization was 24hours, 48hours and 72hours in 4, 8 and 4 patients respectively. 12 patients were transfused after the discovery of the allo-antibodies. That means if we have chosen a delay of validity of 72hours, then 9 patients would have been transfused with a negative result.

Conclusion: Checking for allo-antibodies before RBC transfusion with an interval of 24hours (and not 72hours) is pertinent in order to assure an optimal transfusion safety and to limit the risk of hemolytic transfusion reactions. A pretransfusion testing interval of 24hours for multi-transfused patients should be considered.

Keywords: Antibody identification; Identification des anticorps; Multi-transfused patient; Patient transfusé itératif; Pre-transfusional red cell allo-antibodies screening; Recherche d’agglutinines irrégulières pré-transfusionnelle.