Transfusion with Fibrinogen and Platelet Concentrate: Acute Effects on Platelet Aggregation and Clot Formation
Examensarbete för masterexamen
Andersson Shams Hakimi, Caroline
Cardiac surgery is associated with a risk for excessive blood loss, which increases morbidity and mortality. The increased bleeding after cardiac surgery may be caused by surgical factors, an impaired coagulation, or a combination of both. Transfusion of blood products is used to improve coagulation and platelet function, but transfusions are costly and may have side effects. Therefore, optimizing the use of transfusion products is important. One way to achieve this is to closely monitor the effect of transfusions on coagulation and platelet aggregation. In this thesis, rotational thromboelastometry (TEM) and multiple electrode aggregometry (MEA) were used to examine the ex vivo effects of transfusion of fibrinogen and/or platelet concentrate. Increasing doses of fibrinogen and/or platelets was added to blood from healthy volunteers (n=10), cardiac surgery patients (n=10) and patients treated with platelet inhibitors (n=10). The following variables were analyzed: clotting time (CT) and maximum clot firmness (MCF) with TEM and platelet aggregability with MEA, after addition of different initiators and inhibitors. TEM variables improved after treatment with fibrinogen and platelets in all study groups, without intergroup differences. The effect was not potentiated when the products were simultaneously added. Fibrinogen infusion reduced platelet aggregability in healthy volunteers, but did not influence platelet aggregability in cardiac surgery patients and patients treated with platelet inhibitors. Platelet transfusion increased platelet aggregability in all three groups, but markedly more in the two patient groups. The combination of fibrinogen and platelets were less effective than platelets alone. The effect of platelets and/or fibrinogen on platelet aggregation seemed to be enhanced if the baseline aggregation was suppressed by platelet inhibitors or cardiac surgery. In conclusion, a dissociation among different study populations in the ex vivo platelet aggregation response to fibrinogen and platelet transfusion was demonstrated. The clot formation response to fibrinogen and platelet transfusion was comparable in all three study populations. These results may have impact on future transfusion protocols.
Livsvetenskaper , Industriell bioteknik , Life Science , Industrial Biotechnology