Novel fondaparinux protocol for anticoagulation therapy in adults with renal failure and suspected heparin-induced thrombocytopenia: a retrospective review of institutional protocol

Introduction The literature recommends against the use of fondaparinux in patients with kidney failure and dialysis as it may, with repeated dosing, accumulate and put patients at risk of bleeding. The management of patients with thrombosis in the presence of heparin-induced thrombocytopenia HIT requires the introduction of an alternative anticoagulant like bivalirudin or argatroban. When these drugs are not available, fondaparinux, remains the only alternative. In similar scenarios, there are few studies addressing how to administer it. Methods We developed a protocol for fondaparinux in patients with renal failure where pharmacokinetic parameters are altered, and levels changed only after hemodialysis or in cases of residual renal activity. Patients received a full first dose except for high risk of bleeding. We targeted a peak anti-factor Xa activity level of 0.6–1.3 units/ml and changed the subsequent dose accordingly. Furthermore, we monitored the patients for signs of bleeding, a drop in hemoglobin level, or clinical signs of thrombosis. Discussion We described 10 patients with kidney failure and suspected HIT taking fondaparinux. All the patients achieved therapeutic anti-factor Xa activity levels. However, one developed new-onset venous thromboembolism (VTE) despite therapeutic anti-factor Xa levels. Another patient experienced a bleeding episode. We believe that these two patients developed complications due to their medical conditions rather than the use of fondaparinux. Conclusion Fondaparinux can be safely used in kidney failure using our protocol. However, despite its safety profile and relative success, this case series was small. More robust studies need to be conducted prior to drawing conclusions.