From the Guidelines
Unfractionated heparin (UFH) is the preferred anticoagulant in patients with severe chronic kidney disease (CKD) or those on dialysis, as it is not renally cleared and can be more easily reversed with protamine if bleeding occurs. For UFH, standard initial dosing can be used (typically 80 units/kg bolus followed by 18 units/kg/hour infusion), but more frequent aPTT monitoring is recommended, aiming for an aPTT of 1.5-2.5 times baseline 1. In patients with CKD, the risk of bleeding is increased, and careful consideration of the dose and monitoring of anticoagulation is necessary. The use of UFH in CKD patients is supported by the most recent guidelines, which recommend UFH as the agent of choice in patients with CrCl <30 mL/min 1.
Some key considerations when using UFH in CKD patients include:
- More frequent aPTT monitoring to minimize the risk of bleeding
- Careful consideration of the dose, taking into account the patient's renal function and weight
- Regular monitoring of platelet count, especially in the first 14 days of therapy, to minimize the risk of heparin-induced thrombocytopenia
- Consideration of alternative anticoagulants, such as low molecular weight heparins (LMWHs), in patients with less severe CKD, with dose reduction necessary in severe CKD (CrCl <30 mL/min) 1.
Overall, the use of UFH in CKD patients requires careful consideration of the benefits and risks, as well as close monitoring of anticoagulation and renal function. The most recent guidelines recommend UFH as the preferred anticoagulant in severe CKD or dialysis patients, due to its ease of reversal and lack of renal clearance 1.
From the Research
Considerations for Using Heparin in Patients with CKD
- The use of unfractionated heparin in patients with chronic kidney disease (CKD) requires careful consideration due to the increased risk of bleeding and thromboembolic complications 2, 3, 4.
- Unfractionated heparin is often preferred in patients with severe renal impairment, despite its association with increased bleeding risk, as it does not require dose adjustment with renal dysfunction 2, 4.
- However, low-molecular-weight heparins have largely replaced unfractionated heparin in CKD patients due to fewer incidences of heparin-induced thrombocytopenia and bleeding 3.
- In patients with CKD, anticoagulation therapy should be based on evidence from randomized clinical trials, but CKD patients are often excluded from these trials, making treatment decisions challenging 3, 5.
- The choice of anticoagulant in CKD patients depends on the stage of CKD, with direct oral anticoagulants preferred in mild to moderate CKD and warfarin remaining the first-line treatment in end-stage renal disease 6, 5.
Monitoring and Dosing Considerations
- Close monitoring of anticoagulation is recommended when unfractionated heparin is administered in patients with severe chronic renal impairment 4.
- Dose adjustment of anticoagulants may be indicated when the creatinine clearance falls below 30 mL/min, and lower doses and closer anticoagulation monitoring may be advisable when using low-molecular-weight heparins in patients with chronic renal failure 4.
- Regular monitoring of renal function is essential in CKD patients receiving anticoagulation therapy to optimize treatment and minimize risks 5.
Clinical Practice Recommendations
- Clinicians should consider the benefit-risk ratio of all types of anticoagulants in each stage of CKD and provide practical recommendations for accurate dosage adjustment, reversal of antithrombotic effect, and monitoring of renal function on a regular basis 5.
- A risk-based approach should be employed to determine which patients will benefit from bridging anticoagulation, and either unfractionated heparin or low molecular weight heparin are adequate choices for bridging anticoagulation 6.