Thrombocytopenia (low platelet level) is the most common cause of abnormal bleeding.
PATHOPHYSIOLOGY
Thrombocytopenia can result from decreased production of platelets within the bone marrow or from increased destruction or consumption of platelets. Causes include failure of production as a result of certain anemias, speticemia, and cytotoxic medications; increased destruction as a result of idiopathic thrombocytopenia purpura, lupus erythematosus, malignant, lymphoma, medications (digoxin, phenytoin, aspirin), and postviral infections; and increased utilization, such as results from disseminated intravascular coagulopathy (DIC). Another cause is sequestration; approximately one third of the circulating platelets are within the spleen, so a greatly enlarged spleen results in increased sequestration of platelets.
CLINICAL MANIFESTATIONS
• With platelet count below 50,000/mm3: bleeding and petechiae
• With platelet count below 20,000/ mm3: nosebleeds, gingival bleeding, excessive menstrual bleeding, and hemorrhage after surgery or dental extractions
• With platelet count below 5,000/mm: spontaneous fatal central nervous system hemorrhage or gastrointestinal hemorrhage
ASSESSMENT AND DIAGNOSTIC METHODS
• Bone marrow aspiration and biopsy, if platelets deficiency is secondary to decreased production
• Increased megakaryocytes (the cells from which platelets originate) and normal platelet production in bone marrow, when platelet destruction is the cause
MEDICAL MANAGEMENT
The management of secondary thrombocytopenia is usually treatment of the underlying disease. Platelet transfusions are used to raise platelet count if platelet production is impaired; if excessive platelet destruction is the cause, the patient is treated as indicated for idiopathic thrombocytopenia purpura. For some patients a splenectomy can be therapeutic, although it may not be an option for other patients.
NURSING MANAGEMENT
Intervention focus on preventing injury (e.g. use of soft toothbrush and electric razors, minimize needlestick procedures), stopping or slowing bleeding (e.g. pressure, cold), and administering medications and platelets as ordered, as well as patient teaching.
