Anesthesia & Clinical Research
Open Access

Abstract

Preoperative Low Dose Recombinant Activated Factor VII Effect during Liver Transplantation

Khalil M, Fayed N, Abdullah M, Refaat E, Suliman H, Yassen K, Ibrahim T, Tanaka K and Abdallah A

Background: End stage liver disease patients are prone to coagulopathy and frequently require blood transfusion during transplantation.

Methods: Prospective study (2008-2011) to investigate the effect of prophylactic intravenous administration of low dose recombinant activated factor VII (rFVIIa) (20 μ/kg) 30 min prior to surgery and repeated one hour later on Standard Coagulation Tests (SCTs), Rotational Thromboelastomery (ROTEM) and Blood Transfusion (BT) requirements during Living Donor Liver Transplantation (LDLT). SCT include Prothrombin Time (PT), International Normalized Ratio (INR) of prothrombin time, Activated Partial Thromboplastin Time (aPPT), fibrinogen and platelets blood levels. ROTEM include EXTEM and INTEM representing coagulation extrinsic and intrinsic pathways respectively, and FIBTEM for fibrinogen activity. Blood transfusion was guided by ROTEM parameters. Control group(C), n=25 and rFVII group, n=25

Results: Both groups preoperative MELD scores, ROTEM and SCTs were comparable (P>0.05). After initial dose to end of dissection, a reduction in INR and aPTTin rFVII group versus control were observed, associated with a reduction in clotting time (CT) and increased alpha angle in ROTEM (P<0.05) with no hypercoagulability or thromboembolic findings. Mean BT reduced significantly in rFVII group (p<0.05). 4% of controls received no BT versus 36% in rFVII group (P<0.05). Duration of dissection, hemoglobin (HB) at induction were comparable (p>0.05). BT correlated positively with dissection time (r=0.7, p<0.01), but weakly with preoperative HB (r=-0.3, p<0.05).

Conclusion: Low dose rFVII monitored by ROTEM improved coagulation and reduced BT requirements with no evidence of thromboembolic events. Dissection time was another important contributing factor.