Sarah Bos

75 Hemostatic complications in hepatobiliary surgery 5 is of concern.(94) Position on the use of rFVIIa as a possible rescue agent in patients with intractable bleeding has yet to be defined.(95) Whereas the evidence for the benefits of blood products in perioperative medicine is low, the supporting evidence for transfusion-related complications including transfusion associated lung injury, transfusion-associated circulatory overload, and infectious complications are increasingly acknowledged.(62) As in other types of surgery,(96,97) transfusion of blood products during liver surgery and liver transplantation has been associated with increased morbidity and mortality.(4) Our current practice is in general one of wait-and-see approach to start blood product transfusion only in actively bleeding patients with evidence of hemostatic abnormalities. Point- of-care testing by thromboelastography is used to guide blood product transfusion. In the past two decades, improvements in surgical techniques have had an important impact in improving outcome after liver transplantation. Mainly the introduction of the piggyback technique (liver transplantation with preservation of the recipient vena cava) resulted in lower blood transfusion requirements compared with patients transplanted using the ‘classical’ technique.(98,99) Although the cause of blood loss during liver transplantation is multifactorial, as noted earlier hyperfibrinolysis has been identified as an important component of the hemostatic dysfunction during this procedure. This has provided a scientific basis for the use of antifibrinolytic drugs, in an attempt to restore the balance between coagulation and fibrinolysis and to reduce blood loss. Tranexamic acid and aprotinin have been shown to reduce blood transfusion requirements by approximately 30% during liver transplantation by well-designed, placebo- controlled, randomized trials.(100–102)No increased risk of thromboembolic complications has been shown in any of the randomized controlled trials. Prevention and Treatment of Thrombosis As the hemostatic system following liver surgery is balanced into a hypercoagulable state, with a corresponding risk of thrombotic events, a proactive approach to anticoagulant management after liver surgery appears warranted. Importantly, thromboprophylaxis should not be withheld from patients with a prolonged PT or low platelet count, as these factors unjustifiably suggest a hypocoagulable state and increased bleeding risk. Following partial hepatectomy, pharmacological thromboprophylaxis has been shown to reduce the incidence of postoperative VTE.(6,64,66,103) However, since the risk of thrombotic events, is still appreciable even in those patients receiving optimal thromboprophylaxis, studies on safety and efficacy of more aggressive