Data Entry

Heparin Type

Unfractionated Heparin (UFH): current or within 100 days
Low Molecular Weight Heparin (LMWH): current or within 100 days

Patient Characteristics

Postoperative status; treatment or prophylaxis
Cardiac surgery patient
On Heparin within past 100 days
Acute systemic reation within 30 min.
Other

4 T's Pretest Risk Scoring for HIT

Thrombocytopenia
50% Fall and platelet nadir >20x109/L
30-50% Fall or platelet nadir 10-19x109/L
<30% Fall or platelet nadir <10x109/L

Timing
Between days 5-10 or onset first day with heparin exposure within 30 days
After day 10 or onset first day with heparin exposure within 31-100 days
Before day 4 without recent heparin exposure
Timing unclear

Thrombosis
Proven new thrombosis
Skin necrosis
Acute systemic reaction after IV UFH bolus
Progressive or recurrent thrombosis
Erythematous skin lesions
Suspected (unproven) thrombosis
No thrombosis

oTher Causes of Thrombocytopenia
None evident
Possible
Definite

Results and Recommendations




Results and Decisions

4T's Score


Treatment Recommendations