2025-10-20·7 min read·Pharmacology
Heparin-Induced Thrombocytopenia (HIT) for the NCLEX
Understanding HIT - pathophysiology, assessment, management, and nursing interventions.
What Is HIT?
A serious immune-mediated reaction to heparin that paradoxically causes thrombosis (clot formation) rather than bleeding. Platelet count drops >50% from baseline, typically 5-10 days after starting heparin.
Types
- Type I (non-immune): Mild platelet decrease (rarely <100,000), resolves spontaneously. Common, benign
- Type II (immune): Significant platelet decrease, high thrombosis risk. Life-threatening - requires immediate intervention
Assessment
- Platelet count drops >50% from baseline
- New blood clot formation while on heparin
- Signs of DVT, PE, or arterial thrombosis
- Skin necrosis at injection site
Management
- STOP all heparin immediately (including heparin flushes, heparin-coated catheters)
- Start alternative anticoagulant: argatroban or bivalirudin (direct thrombin inhibitors)
- Do NOT give warfarin until platelets recover (can worsen thrombosis)
- Never re-expose client to heparin
- Document heparin allergy
Prevention
Monitor platelet count every 2-3 days during heparin therapy. Educate client to inform all future providers about HIT diagnosis.
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