Sarah Bos

97 Efficacy of pro- and anticoagulant strategies in plasma 6 Dabigatran was much more effective in inhibiting thrombin generation in patients compared to controls, with lower ETP values in the presence of dabigatran in patients compared to controls. In contrast, rivaroxaban was much less effective in patients compared to controls, and consequently the absolute ETP values in the presence of rivaroxaban were substantially higher in patients compared to controls, with ETP values in the presence of rivaroxaban in patients approximating ETP values in absence of rivaroxaban in controls. In vitro efficacy of pro- and anti-hemostatic agents in samples taken during and after partial hepatectomy We next studied changes in routine hemostatic tests and total thrombin generation in samples taken during and after partial hepatectomy. The INR increased during and after surgery, and started to normalize at day 3. Plasma fibrinogen was slightly elevated at the start of surgery, decreased during surgery, and was substantially elevated thereafter until day 6. Antithrombin levels were normal in patients at the start of surgery, but decreased during surgery and did not normalize until day 6 (supplementary figure 2). Patients generatedmore thrombin as compared to controls throughout the procedure, which is in line with our previously published data(19), except for elevated thrombin generation at baseline (Supplementary table 2). In the samples taken from patients during and after partial hepatectomy changes in thrombin generation after addition of pro- and antihemostatic drugs were also tested. Figure 3 shows absolute ETP values of patients and controls in absence or presence of procoagulant agents, with ETP values in absence or presence of anticoagulant agents shown in figure 4. Statistical differences indicated are differences in proportional change in ETP upon addition of pro- or anticoagulants between controls and patients. Supplementary table 2 shows absolute ETP values and percentual differences between ETP values in absence and presence of pro- or anticoagulant agents, with significance levels relative to the healthy control group. Addition of pooled normal plasma and recombinant factor VIIa resulted in very little change in thrombin generation in patients and controls. In contrast, PCCs substantially increased thrombin generation in patients and controls, and although the magnitude of the increase was similar between patients and controls, absolute ETP values were substantially higher in patients due to higher thrombin generation in the absence of PCC, particular at the end of surgery. LWMH had a similar anticoagulant effect in patients and controls although absolute ETP values in the presence of LMWH were very high in patients, with values even higher than control values in the absence of LMWH. At start of surgery anticoagulant activity of LWMH was clearly higher in patients. With the addition of UFH the relative decrease of the ETP in patients was comparable to the controls in