3.5 Blood component transfusion

There is controversy over the benefit of using FFP, cryoprecipitate and platelet concentrates to improve haemostasis in both procedural and non-procedural settings. In the absence of high-quality evidence, clinicians have traditionally relied on laboratory indexes for making decisions about transfusion of these products. The systematic review considered purported ‘transfusion-trigger’ levels of these various indexes, excluding studies of patients with massive bleeding or requiring warfarin reversal.

Question 5 was originally defined as a prognostic question. It was expected that the best evidence relating to this question would come from large cohort studies that stratified results according to baseline international normalised ratio (INR)/fibrinogen/platelet count. However, the literature search for this module identified a number of highly relevant RCTs that compared different transfusion triggers. Therefore, the CRG decided that this question would be approached initially as an interventional question, and then as a prognostic question if relevant evidence from RCTs was not found. High-quality evidence from RCTs was found for platelet transfusion; hence, this part of the question was treated as an interventional question. In contrast, studies relevant to use of cryoprecipitate and FFP were primarily cohort studies in which patients were stratified by INR, prothrombin time/activated partial thromboplastin time (PT/APTT) or fibrinogen at baseline. Hence, these parts of the question were treated as prognostic questions.