Hypercoagulation Symptoms: MI, stroke, limb and organ ischaemia, DVT, PE
Fever, chills, flushing or the skin
Timing of Platelets fall
Thrombocytopenia from other causes
Type I Immune Mediated - platelets normally between 100 and 150. Self limiting. 2 days after heparin administration.
Type II Immune Mediated - Platelet IgG (which cause release of pro-coagulant factors and acute inflammation) complexes removed by splenic macrophages. Thrombocytopaenia >50% in 5-15 days of heparin adminstration.
If someone has had heparin before, this happens quicker.
Fundaparinox induced HIT is rare.