Single Low Dose of rFVIIa Combined with Antifibrinolytic Agent is a Simple and Safe Treatment for Factor XI-Deficient Patients undergoing Surgery.

Abstract

Factor XI (FXI) deficiency is a rare autosomal bleeding disorder. The rarity of spontaneous bleeding and absence of optimal tools to predict the bleeding risk in FXI-deficient patients hamper the standardization of prophylactic treatment enabling them to undergo major surgeries without blood products. We explored the effectiveness of a single and very low dose of recombinant factor VIIa (rFVIIa) along with tranexamic acid (TXA) as prophylactic treatment for FXI-deficient patients undergoing various types of surgery at various sites of injury. We studied the potential use of thrombin generation (TG) as a surrogate tool for predicting thrombogenicity. Our cohort consisted of 10 patients with severe FXI deficiency undergoing 12 interventions. Patients received a single dose of 10 to 15 μg/kg rFVIIa at the end of surgery in addition to TXA initiated 2 hours before surgery at the dose of 4 g/day for 3 to 5 days. TG was tested before and 30 minutes after rFVIIa administration. All operations were uneventful and none of the patients bled excessively or required blood products. No thrombotic event was reported, and the postoperative hospitalization duration was comparable to that of patients without bleeding disorders. TG performed at the peak of rFVIIa was below the curve of healthy controls, thus confirming that the administered dose was not thrombogenic. A single very low dose of rFVIIa along with TXA is a simple and safe treatment to control hemostasis in severe FXI-deficient patients undergoing diverse type of surgical procedure at various sites.