Chapter 134: Acquired Bleeding Disorders

INTRODUCTION

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

ACQUIRED PLATELET DEFECTS

Clinical Features

Patients with platelet disorders commonly present with petechiae or mucosal bleeding. Splenomegaly may be noted in patients experiencing platelet sequestration.

Diagnosis and Differential

Acquired platelet abnormalities include quantitative and qualitative defects. Quantitative platelet disorders may be caused by decreased platelet production (marrow infiltration, aplastic anemia, drugs, viral infections, and chronic alcohol use), or 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 renal disease, liver disease, DIC, drugs (aspirin, NSAIDs, clopidogrel), and myeloproliferative disorders.

Emergency Department Care and Disposition

1. Circulatory stabilization of the acutely bleeding patient is paramount, including volume resuscitation, packed red cell transfusion, and pressors as necessary.

2. Perform a focused history and physical; order appropriate laboratory studies. Most evaluations of bleeding patients will include a CBC with peripheral smear. Other studies to consider include PT/INR, PTT, basic metabolic panel, type and screen, and fibrinogen.

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

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

BLEEDING IN IMMUNE THROMBOCYTOPENIA

Emergency Department Care and Disposition

In general, patients with a platelet count >50,000/mm³ require no treatment. Patients with a platelet count <30,000/mm³ and patients with a platelet count of <50,000/mm³ with bleeding typically require treatment.

1. Treatment options include corticosteroids, such as prednisone 60 to 100 mg PO daily (onset of action 4 to 14 days).

2. Immunoglobulin 1 g/kg daily IV (onset of action 1 to 3 days) is usually reserved for patients with very low platelet counts and bleeding.

3. If transfusing platelets, generally two to three times the usual dose is required due to circulating antibodies.

ACQUIRED COAGULATION DEFECTS

Coagulation disorders often present with significant hemorrhage and frequently involve platelet defects as well.

Bleeding in Liver Disease

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. Transfuse red cells as needed.

2. Transfuse platelets for thrombocytopenia <60,000/mm³.

3. Consider transfusion of fresh frozen plasma 15 mL/kg IV with caution. It may increase the risk of thrombotic complications, and it may ...