Fig. 14.1. The rapid infusion system (Haemonetics, Inc., Braintree, Mass).

intervention may allow normalization of the coagulation with less blood products and reduced time for complete surgical hemostasis. Blood coagulability is determined by TEG, platelet count, and routine coagulation tests (PT, PTT, fibrinogen level), but observation of the surgical field reveals invaluable information. TEG measures global hemostasis of plasma proteins and platelet interactions. Only TEG shows fibrinolysis in a timely manner. In addition, TEG allows the in-vitro use of pharmacologic intervention, greatly expanding the value of this monitoring technique (Figs. 14.2, 14.3). However, some feel that TEG lacks the specificity for guiding blood component replacement that is found with measuring platelets, fibrinogen, PT, and PTT. Thus in problem cases both systems may have a role. The frequency of hemostatis testing is determined by the degree of coagulation dysfunction, the degree of surgical difficulty, and the surgical field.

Blood component therapy is based on hemostatic testing, TEG, and adequacy of surgical hemostasis. When component replacement is indicated, it should be done to a level of adequacy, not normality. Patients may have successful transplants with only moderate blood loss with platelet counts of 40-50,000,000/mL or fibrinogen concentrations of 100-125 mg/dL. When fibrinolysis is present, epsilon-aminocaproic acid is frequently used for reversal, and some programs use continuous administration for prophylaxis. In either approach very low doses are usually effective (single dose 250-500 mg). Aprotinin has been advocated, with some data suggesting decreased blood loss. Others are concerned about the potential for thrombosis with the prophylactic use of antifibrinolytic agents, and additional research is required. After graft reperfusion, heparinoid effect can be seen even after flushing of the donor organ, but protamine reversal is rarely necessary.

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