الفهرس 
Physiological BackgroundOnly 14 pages are availabe for public view
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Abstract
Heparin-Induced thrombocytopenia (HIT) is thrombocytopenia or thrombosis plus one or more positive tests for HIT antibodies.
To diagnose HIT, platelet count monitoring ; at least every other day until hospital discharge or postoperative day 14 (whichever occurs sooner): A platelet count fall of 50% or greater from baseline or any thrombosis that occurs 5 to 14 days after cardiac surgery is suggestive of HIT, even when heparin is not being given in the postoperative period. Spontaneous bleeding is uncommon in patients with HIT.
Laboratory confirming assays are helpful especialy washed platelet activation assays (e.g., platelet serotonin release assay or the heparin-induced platelet activation test).
In patients receiving unfractionated heparin after cardiac surgery, the frequency of HIT is 1% to 3% by postoperative days 5 to 14. At least 50% of patients with HIT develop arterial or venous thrombotic complications, often beginning after heparin has been stopped because of suspicion of HIT.
The 1st line to manage HIT is to discontinue all heparin if there is a high suspicion of HIT.
In general, HIT-associated thrombosis should be treated with one of the alternative anticoagulant groups
• Direct thrombin inhibitors as lepirudin , argatroban, or bivalirudin.
• Danaparoid sodium (factor X inhibitor)
Warfarin and other oral anticoagulants are contraindicated during acute HIT; Oral anticoagulants should be delayed pending substantial recovery of the platelet count. Low-molecular-weight heparin is contraindicated for treatment of HIT. Prophylactic platelet transfusions should be avoided when HIT is strongly suspected, as it may increase the thrombotic risk.