Heparin and Warfarin Monitoring

Unfractionated heparin is monitored via aPTT, with a therapeutic range typically 1.5-2.5 times the control value, and its antidote is protamine sulfate. Low molecular weight heparin (enoxaparin) has more predictable dosing and generally doesn't require routine aPTT monitoring. Warfarin is monitored via INR, with a therapeutic range of 2-3 for most indications, and its antidote is vitamin K; warfarin also requires consistent vitamin K dietary intake since fluctuating intake of leafy greens affects INR stability. A key testable difference: heparin works immediately and is used for acute anticoagulation, while warfarin takes days to reach therapeutic effect, so the two are often overlapped during transition.

Direct Oral Anticoagulants (DOACs)

DOACs like apixaban, rivaroxaban, and dabigatran don't require routine coagulation monitoring, making them convenient, but they still carry bleeding risk and require renal function assessment since several are renally cleared. Dabigatran's antidote is idarucizumab, and andexanet alfa reverses factor Xa inhibitors like apixaban and rivaroxaban in life-threatening bleeds. DOACs have fewer food and drug interactions than warfarin, improving adherence, but the NCLEX tests whether you know they still require caution with concurrent NSAID or aspirin use due to additive bleeding risk, and that missed doses shouldn't be doubled up.

Bleeding Precaution Teaching

All anticoagulated clients need teaching on using a soft-bristle toothbrush, electric razor, avoiding contact sports, and reporting unusual bruising, blood in urine or stool, or prolonged bleeding from cuts. Instruct clients to inform all providers and dentists about anticoagulant use before procedures. Assess for internal bleeding signs like severe headache (possible intracranial bleed), abdominal pain, or hypotension with tachycardia. NCLEX questions often present a client on anticoagulants with a new headache or dizziness and expect you to recognize this as a potential bleeding emergency requiring immediate provider notification rather than routine reassurance.