Background and aim of work: Hypercoagulability can lead to serious thromboembolic events. The aim is to assess perioperative coagulation status in recipients with genetic and acquired tendency to hypercoagulability. 
Methods: A prospective observational study with 43 consecutive recipients (South African Cochrane Registry 201405000814129). Two or more of following inclusion criteria were used: low protein C, low protein S, low antithrombin, abnormal Factor V Leiden mutation, increased lupus anticoagulant, increased homocystein IgG/IgM, and increased anti-phospholipid antibodies. Rotational thromboelastometry (ROTEM) (EXTEM, INTEM and FIBTEM assays) and conventional coagulation tests (CCT) were assessed preoperative, during surgery and on postoperative days 1, 3 and 7. ROTEM was used to guide blood transfusion. Heparin was infused postoperatively for 3 days (60-180 U/kg/day) and replaced by low molecular weight heparin (20 mg/12 h) 
Results: Postoperative FIBTEM (MCF) gradually increased above reference range (Day 7) despite normal fibrinogen plasma levels (P<0.05). EXTEM and INTEM significantly changed with transplant phases (P<0.05), but with no hypercoagulability observed. No significant correlation was found between ROTEM and CCT.  INTEM CT (reference range, 100-240 sec) normalize on days 3 and 7 (199.5±73.5 and186.9±67.01, respectively), despite prolonged aPTT (62.5±17.9 and 48.4±15.7, respectively; reference range 35-45 sec). Partial thrombosis of Hepatic artery and portal vein were reported in 5/43(11.62%) and 2/43 (4.65%), respectively, with high FIBTEM (MCF) in 5 /7. Intraoperative Mean+SD units consumed (transfused patients/overall patients) of red blood cells 8.80±5.82(35/43), fresh frozen plasma 8.62±4.07 (27/43) and cryoprecipitate 12±4 (12/43). No postoperative transfusion was required. Transplant indications were hepatitis C (83.7%), combined with carcinoma (37.2%).  Increased lupus anticoagulant, decreased antithrombin III and decreased protein C reported in 88.4%, 86.2% and 74.4%, respectively, with Factor V Leiden mutation positive in 25.6%. 3 month and one year survival was 74.5% and 61.3% 
Conclusion: A significant postoperative step-wise increase in FIBTEM MCF to beyond normal reference range despite normal fibrinogen plasma levels in this study population. FIBTEM as a predictor for thromboembolic events need to be investigated further with a larger number of recipients, particularly after one week when CCTs fails to diagnose the condition.

Perioperative rotational thromboelastometry during and after adult living donor liver transplant recipients with genetic and acquired tendency to hypercoagulability