Fibrinogen concentrate improves clot strength in patients with haematological malignancies requiring platelet transfusion

SUMMARY Background Patients with bone marrow failure secondary to chemotherapy often develop thrombocytopenia and require platelet transfusion. Fibrinogen plays an important role in platelet aggregation and the establishment of the primary haemostatic plug. Objectives To compare the effects of in vivo platelet transfusion on clot firmness in thrombocytopenic patients with in vitro ‐performed fibrinogen concentrate substitution. Materials and methods Thirty patients with haematological malignancy admitted for platelet transfusion were included. Haemostatic effects from platelet transfusion and ex vivo addition of fibrinogen concentrate at three different doses were evaluated by thromboelastometry, with clot firmness as the primary endpoint ( A30 ExTEM assay). Secondary endpoints were other thromboelastometry parameters, thrombin generation parameters, activated partial thromboplastin time ( APTT ), prothrombin time PT , fibrinogen and factor XIII levels and a clinical bleeding score. Results Twenty patients (66%) had clinical bleeding signs by prior to transfusion. Platelets increased from 17 (range, 1–109) to 40 (range 2–139) × 10 9  L −1 following transfusion, with a median corrected count increment of 16·7 (range, 0·8–43·5). The A30 value increased significantly by platelet transfusion from 35 ± 11 to 47 ± 10 mm, with no changes in thrombin generation. Fibrinogen concentrate dose‐dependently increased A 30 (to 43 ± 10, 49 ± 9 and 50 ± 9 mm, respectively) and reduced parameters of thrombin generation at high doses. Platelet transfusion, together with fibrinogen concentrate, further increased clot firmness. APTT and PT were within normal range, whereas fibrinogen levels were slightly elevated. Conclusion Fibrinogen concentrate increased clot firmness to the same degree as platelet transfusion in patients with low platelet count requiring platelet transfusion.