Chapter 134. Acquired Bleeding Disorders

Platelet abnormalities, drugs, systemic illness, and endogenous anticoagulants can cause acquired bleeding disorders.

Clinical Features

Patients with thrombocytopenia or dysfunctional platelets commonly present with pethechiae, most evident in the lower extremities. Patients may also exhibit gingival bleeding, epistaxis, purpura, hematuria, and menorrhagia. Splenomegaly may be noted in patients experiencing platelet sequestration.

Diagnosis and Differential

Acquired platelet abnormalities include quantitative (thrombocytopenia) and qualitative (dysfunctional) defects. Quantitative platelet disorders include those caused by decreased platelet production (marrow infiltration, aplastic anemia, drugs, viral infections, and chronic alcohol use), and increased platelet destruction (idiopathic thrombocytopenic purpura (ITP), thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome, disseminated intravascular coagulation (DIC), viral infections, drugs and HELLP syndrome). Other causes include acute hemorrhage, hemodialysis and splenic sequestration. Qualitative platelet disorders are commonly associated with uremia, liver disease, DIC, drugs (aspirin, NSAIDs, clopidogrel), myeloproliferative disorders, and antiplatelet antibodies. Initial laboratory testing should include a CBC with peripheral smear.

Emergency Department Care and Disposition

1. Consult with a hematologist as subtleties in diagnosis and treatment exist. For example, some conditions may be worsened by platelet transfusion (DIC and TTP).

2. Consider platelet transfusion in patients with a platelet count <10 000/mm3 or active bleeding with platelets <50 000/mm3.

3. Treatment and disposition of patients with ITP varies with age, severity, and symptoms. In general, patients with a platelet count >50 000/mm3 require no treatment. Patients with a platelet count <20 000 to 30 000/mm3 and patients with a platelet count of <50 000/mm3 with bleeding typically require treatment. Treatment options include corticosteroids, such as prednisone 60 to 100 milligrams PO daily. Immunoglobulin 1gram/kilogram daily IV is usually reserved for patients with very low platelet counts and bleeding.

Patients with liver disease have an increased risk of bleeding for multiple reasons including decreased synthesis of vitamin K–dependent coagulation factors (II, VII, IX, and X), thrombocytopenia, and increased fibrinolysis.

Emergency Department Care and Disposition

1. Administer vitamin K 10 milligrams PO/IV to patients with significant liver disease who are actively bleeding.

2. Use fresh-frozen plasma 15 mL/kg IV to temporarily replace coagulation factors in patients with active bleeding and coagulopathy, or prior to any invasive procedure.

3. In patients with active bleeding: replace fibrinogen with cryoprecipitate 1 unit/5 kilograms IV if fibrinogen levels <100 milligrams/dL, consider platelet transfusion if thrombocytopenic; desmopressin 0.3 microgram/kilogram SC or IV may shorten bleeding times in some patients.

A variety of hemostatic defects are associated with renal disease including platelet dysfunction due to uremic toxins, deficiency of coagulation factors, and thrombocytopenia.

Emergency Department Care and Disposition

1. Treat acute bleeding with transfusion of packed red blood cells.

2. Hemodialysis improves platelet function transiently for 1 to 2 days.

3. Desmopressin 0.3 microgram/kilogram SC or IV shortens bleeding time in most patients.

4. Conjugated estrogen 0.6 milligram/kilogram IV daily for 5 days improves both the bleeding time and clinical bleeding in 80% of patients.

5. Transfuse platelets and cryoprecipitate for life-threatening bleeding only. Use in conjunction with red blood cells, desmopressin and estrogens.

Clinical Features

The clinical features of DIC are a result of simultaneous hemorrhage and thrombosis and vary according to the underlying illness. Bleeding typically predominates and can range from pethechiae to diffuse hemorrhaging from GI/GU tracts, surgical wounds, and venipuncture sites. Patients may present with mental status changes, focal ischemia, oliguria, renal cortical necrosis, acute lung injury, and may develop multisystem organ failure.

Diagnosis and Differential

The diagnosis is based on history, clinical presentation, and associated laboratory abnormalities. Clinical conditions associated with DIC are listed in Table 134-1. Laboratory abnormalities are listed in Table 134-2. The differential diagnosis includes primary fibrinolysis and coagulopathy due to severe liver disease.

Emergency Department Care and Disposition

1. Treat the underlying illness and provide hemodynamic support (IV fluid resuscitation, red blood cells, and inotropic agents).

2. Administer cryoprecipitate to patients with hypofibrinogenemia and active bleeding, with the goal of raising fibrinogen levels to 100 to 150 milligrams/dL.

3. Transfuse platelets if counts <20 000/mm3 or <50 000/mm3 with active bleeding.

4. Transfuse fresh frozen plasma if bleeding is present.

5. Administer vitamin K.

6. The role of heparin remains unclear.

Patients with acquired factor VIII inhibitors (hemophilia A) present with spontaneous bruising and hematomas, whereas those with antiphospholipid antibodies (lupus anticoagulant and anticardiolipin antibodies) typically present with thrombosis. Consult with a hematologist for management of acute bleeding in patients with factor VIII inhibitor. Treatment options include factor VIII, factor XI complex, recombinant factor VIIa, desmopressin, and plasmapheresis.

Hypercoagulable states may be either inherited (activated protein C resistance/factor V Leiden mutation, protein C deficiency, protein S deficiency, antithrombin deficiency or acquired hypercysteinemia) or acquired (antiphospholipid syndrome, pregnancy, oral contraceptives/hormone therapy, malignancy, heparin-induced thrombocytopenia (HIT), and hyperviscosity syndrome). Suspect a hypercoagulable state in young patients without other risk factors and patients with a family history of thromboembolism, recurrent thromboembolic events, or thromboembolic events in unusual sites. Consider HIT in patients with a drop in platelet count of >50% 5 to 15 days after starting heparin. Diagnostic testing for the specific hypercoagulable state is usually beyond the scope of the ED. Initial management of thrombosis consists of low molecular weight heparin or unfractionated heparin. (Chapter 25) An exception to this is patients with HIT in whom heparin must be stopped and another anticoagulant, such as lepirudin, argatroban, danaparoid, initiated in consultation with a hematologist.