Coagulation disorders laboratory tests

Finally, laboratory tests to check the coagulation status of the patient including INR, PTT, and platelets should be available prior to the procedure. In the case of severe coagulation disorders (INR >1.5, PTT >2 normal value, platelets <50,000) these should be corrected prior to stent insertion. 

Screening for coagulation disorders or impairment, as well as for active anticoagulant and/or antiplatelet medication relies first on history and physical exam. Preoperatively, pertinent conditions and medications must be meticulously reviewed. Focused laboratory testing should follow only if indicated (INR, aPTT, fibrinogen level, platelet count platelet fimction testing thromboelas-tometry). 

A revealing assay. Suppose that you have just examined ayoung hoy with a bleeding disorder highly suggestive of classic hemophilia (factor VIII deficiency). Because of the late hour, the laboratory that carries out specialized coagulation assays is closed. However, you happen to have a sample of blood from a classic hemophiliac whom you admitted to the hospital an hour earlier. What is the simplest and most rapid test that you can perform to determine whether your present patient also is deficient in factor VIII activity ... 

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