week 11: disorders of the platelets

bleeding disorders

failure of normal hemostatic mechanisms, provoked by trauma or occurs spontaneously

causes/risk factors

• platelet deficiency, platelet defects, inherited or acquired coagulation factor, vasculature defect 

  • severity and duration of thrombocytopenia, sepsis, increased ICP, liver and renal dysfunction, alcohol abuse, dysproteinemia

• bone marrow may be stimulated to increase platelet production; platelets can also be increased due to splenectomy

platelets

platelets, or thrombocytes, are cellular components of blood involved in blood coagulation; play an essential role in bleeding

• each megakaryocyte produces 2000 platelets; 80% in circulation,

       20% stored in the spleen

normal Platelet count: 150,000 - 400,000 cells/mm³

• 20,000 cells/mm³ and less

  • petechiae, nasal and gingival bleeding, excessive menstrual bleeding, excessive bleeding from surgery or dental procedures

• 5,000 cells/ mm³ and less

  • spontaneous and potentially fatal bleeding in the CNS or GI tract

• risk of bleeding greater when platelet count is mildly reduced if medication-induced or disease-related

thrombocytopenia

low platelet count; results from reduced production of platelets in the bone marrow, increased destruction of platelets, or increased consumption of platelets

causes:

• hematological malignancies (ie. Leukemia) biggest cause

• bone marrow metastases

• anemias

• medications and toxins

• infection

• chronic alcohol use

• chronic liver disease

• chemotherapy

• radiation therapy

• sequestration in spleen

• antibodies (ie. ITP, lupus)

• major bleeding

• disseminated intravascular coagulation (DIC)

assessment:

• neurological: headache, blurred vision, mental status changes

• oral mucosa: gingival bleeding

• nose: epistaxis

• skin: easily bruising, purpura (petechiae, ecchymosis), hematomas, bleeding at puncture sites

• cardiovascular: hypotension, tachycardia, dizziness, diaphoresis

• respiratory: tachypnea, respiratory distress, hemoptysis

• gastrointestinal:  abdominal distention, hematemesis, hematochezia, black tarry stool, stool occult blood

• genitourinary:  hematuria, vaginal or urethral bleeding

diagnostics findings:

• CBC

• BMA or biopsy

• LFTs

• peripheral smear

• coagulation studies

medical management:

• treat underlying condition

• discontinue medication, no alcohol

• platelet transfusion

• splenectomy

• delay or decrease dose of chemotherapy, only if possible

nursing management:

-bleeding precautions

• avoid rectal temperature, suppositories, enemas

• avoid IM injections and urinary catheters, if possible

• smallest needle possible, apply direct pressure to puncture sites 5-10 minutes

• caution against forceful nose blowing and coughing

  promote safety, fall precautions

  @ home:

  • use soft-bristle toothbrush

  • avoid mouthwashes, flossing

  • use electric razor for shaving

  • use emery board for filing nails

  • keep lips moisturized

  • encourage foods easy to chew

  • encourage daily fluid intake of 3L

  • oral stool softeners as prescribed, increased fiber diet

-patient ed.

• avoid contact sports

• limit aggressive manual labor

• use water-based lubricant before sexual intercourse

• clutter-free and safe environment

• avoid aspirin, NSAIDs, alcohol

• notify HCP if need dental work or invasive procedures

• identify and report s/s of bleeding

• how to stop bleeding (ie. apply pressure to site)

• follow-up with CBC and appts

immune thrombocytopenic purpura

• an autoimmune condition where the body attacks platelets, increasing the risk of bleeding; also known as idiopathic thrombocytopenic purpura; platelet count less than 100,000/mm³ with no explicable cause is the primary criterion for diagnosis

primary ITP: acquired immune disorder characterized by thrombocytopenia resulting from pathologic anti-platelet antibodies, impaired production of mega-karyocytes, and T-cell mediated destruction of platelets

secondary ITP: from underlying disorders such as autoimmune disorders (lupus, RA), HIV, Hep C, or H. Pylori infection, or certain medications

clinical manifestations:

• often asymptomatic; s/s of bleeding, anemia

• those who only bruise with petechiae have fewer complications from bleeding; those bleeding from mucosal surfaces (GI tract or respiratory) is described as “wet purpura,” have a greater risk of life-threatening bleeding

diagnostic findings:

• CBC

• BMA

• HIV and hep c testing

medical management:

• achieve a platelet count high enough to maintain hemostasis

• treatment not necessary until bleeding becomes severe

  • discontinue medication-inducing agent

  • corticosteroids: first line treatment; short term use; dampen immune response and increase platelet count

  • IVIG, low-dose chemotherapy; reduce platelet destruction by antibodies

  • thrombopoietin growth factor

  • splenectomy (if drug therapy is ineffective): spleen is the site of most platelet destruction

    • infection risk! avoid large crowds, should receive influenza, pneumococcal, and meningococcal vaccines approx. 2 weeks prior to splenectomy, or 2-3 weeks postoperatively if performed emergently

• NO PLATELET TRANSFUSIONS!!!

  antiplatelet antibodies bind with transfused platelets, causing them to be destroyed. platelets may drop further after transfusion; can result in catastrophic bleeding in patients with wet purpura. body will attack platelets

nursing management:

• protection from bleeding episodes and injury

• obtaining prescriptive, OTC medication, herbal supplements, nutritional supplement history [Chart 29-9] 

• assess for history of viral illness

• same assessment as thrombocytopenia (slide 6)

• same nursing management as thrombocytopenia

• patients receiving corticosteroids: education on bone mineral density scan, supplemental calcium and vitamin D, and dental care