From the Guidelines
For a patient with a history of heparin-induced thrombocytopenia (HIT) on dialysis, the indicated VTE prophylaxis is a non-heparin anticoagulant, preferably argatroban or bivalirudin, as recommended by the American Society of Hematology 2018 guidelines 1. The choice of agent may be influenced by drug factors, patient factors, and experience of the clinician.
- Argatroban should be initiated at a reduced dose of 0.5-1.2 mcg/kg/min as a continuous infusion with dose adjustments based on aPTT monitoring, aiming for an aPTT of 1.5-3 times baseline.
- Alternatively, bivalirudin can be used at 0.03-0.2 mg/kg/hr, also with aPTT monitoring.
- Fondaparinux (2.5 mg subcutaneously once daily) may be considered in patients with normal renal function, but dose adjustment is required in renal impairment and it's generally avoided in dialysis patients.
- Direct oral anticoagulants, such as rivaroxaban, may be considered in clinically stable patients at average risk of bleeding, with a dose of 15 mg twice per day for 3 weeks followed by 20 mg once per day 1. During dialysis sessions, the dialysis circuit should be anticoagulated with the same agent. This approach is necessary because all forms of heparin (unfractionated and low molecular weight) are absolutely contraindicated in patients with a history of HIT due to the risk of triggering a potentially life-threatening immune response that can cause severe thrombocytopenia and thrombosis. Regular monitoring of platelet counts and anticoagulation parameters is essential throughout treatment, as suggested by previous guidelines 1.
From the FDA Drug Label
Argatroban Injection is indicated for prophylaxis or treatment of thrombosis in adult patients with heparin-induced thrombocytopenia (HIT). The indicated VTE prophylaxis for a patient with a history of HIT on dialysis is Argatroban.
- The initial dose of argatroban for adult patients without hepatic impairment is 2 mcg/kg/min, administered as a continuous infusion.
- Monitoring therapy with Argatroban Injection is done using the aPTT with a target range of 1.5 to 3 times the initial baseline value (not to exceed 100 seconds) 2.
From the Research
Indicated VTE Prophylaxis for Patients with a History of HIT on Dialysis
- For patients with a history of heparin-induced thrombocytopenia (HIT) on dialysis, the choice of venous thromboembolism (VTE) prophylaxis is crucial to prevent further thrombotic complications 3, 4.
- Alternative anticoagulation options such as regional citrate infusion during hemodialysis, warfarin, danaparoid, and lepirudin have been considered for these patients 3.
- However, the use of danaparoid and lepirudin may be limited due to their prolonged half-lives in patients with renal failure and high cost 3.
- Newer anticoagulants such as argatroban, fondaparinux, and direct-acting oral anticoagulants (e.g., rivaroxaban, dabigatran, apixaban) have been proposed as potential options for VTE prophylaxis in patients with a history of HIT 5, 4.
- The choice of anticoagulant should be individualized based on the patient's renal function, bleeding risk, and other clinical factors 6.
- Close monitoring of anticoagulation is recommended when using anticoagulants in patients with severe chronic renal impairment 6.
Considerations for Anticoagulant Use in Patients with Renal Impairment
- Patients with renal failure have an increased risk of both thrombotic and bleeding complications, and estimation of renal function is necessary when prescribing antithrombotic drugs 6.
- Dose adjustment of anticoagulants may be indicated when the creatinine clearance falls below 30 mL/min, and close monitoring of anticoagulation is recommended in patients with severe chronic renal impairment 6.
- Some anticoagulants, such as fondaparinux, should be avoided or used with caution in patients with severe renal impairment due to the increased risk of bleeding complications 6.