Anticoagulation Options

Parenteral Agents

Unfractionated Heparin (UFH):

1. Mechanism: Binds to antithrombin, enhancing its inhibitory effect on thrombin and factor Xa.
2. Dosing: Administered by continuous intravenous infusion; monitored using activated partial thromboplastin time (aPTT).
3. Clinical Pearls: Frequent aPTT monitoring is crucial to maintain therapeutic levels.

Low Molecular Weight Heparin (LMWH):

1. Mechanism: Selectively inhibits factor Xa.
2. Dosing: Subcutaneous administration based on weight; monitoring not required.
3. Clinical Pearls: Preferred over UFH due to predictable dosing and reduced risk of heparin-induced thrombocytopenia (HIT).

Fondaparinux:

1. Mechanism: Binds to antithrombin, inhibiting factor Xa.
2. Dosing: Subcutaneous administration; renal dosing adjustments required.
3. Clinical Pearls: Suitable for outpatient management, particularly in low-risk patients.

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Transition to Oral Anticoagulation

Direct Oral Anticoagulants (DOACs):

1. Mechanism: Directly inhibit factor Xa (rivaroxaban, apixaban, edoxaban) or thrombin (dabigatran).
2. Dosing: Fixed doses; no routine monitoring required.
3. Clinical Pearls: Rapid onset, predictable anticoagulant effect, and fewer drug interactions compared to warfarin.

Warfarin:

1. Mechanism: Interferes with vitamin K-dependent clotting factors.
2. Dosing: Requires careful dosing adjustments; monitored using international normalized ratio (INR).
3. Clinical Pearls: Slow onset, frequent INR monitoring, and potential drug interactions.