HIT Expert Probability (HEP) Score
Calculates probability of heparin-induced thrombocytopenia (HIT). More complex than 4Ts; validated in post-surgical and critically ill patients. Use alongside anti-PF4 antibody testing.
Score interpretation
HEP < 2. Low probability of HIT. Continue heparin if clinically needed.
→ HIT unlikely. Investigate alternative causes of thrombocytopenia. Routine PF4 antibody testing not required.
HEP 3-8. Intermediate probability. Clinical judgment required.
→ Check anti-PF4 antibody (ELISA). Consider switching to non-heparin anticoagulant pending result. Involve haematology.
HEP >= 9. High probability of HIT.
→ Stop all heparin immediately. Switch to argatroban, bivalirudin, or fondaparinux. Send PF4 antibody + confirm with serotonin release assay. Platelet transfusion generally contraindicated.
Interpretation bands for the HEP Score. Apply clinical judgement and local guidance.
References
- Cuker A, et al. Predictive value of the 4Ts scoring system for heparin-induced thrombocytopenia. J Thromb Haemost. 2012;10(4):648-55.
Related
Curated clinical cross-links plus same-class fallbacks.
- Protamine Sulphate · Heparin Reversal Agent
- Unfractionated Heparin (ACS / PCI) · Anticoagulant / ACS / PCI
- Bivalirudin (PCI Anticoagulation) · Direct Thrombin Inhibitor / PCI
- Protamine Sulphate (Heparin Reversal) · Heparin Reversal / Cardiac Surgery
- Heparinoid · Topical heparin analogue
- Unfractionated Heparin (IV) · Anticoagulant — ACS / PE / Thrombus
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.