RBC

Hematology: RBC Disorders

Objectives

  • Understand and describe the pathophysiology of bleeding and clotting disorders.
  • Describe the clinical manifestations of bleeding and clotting disorders.
  • Understand and discuss the treatment of bleeding and clotting disorders.
  • Understand and discuss the nursing care for bleeding and clotting disorders.

Hemochromatosis

Definition
  • Hemochromatosis is a disorder leading to excess iron accumulation in the body.
Causes
  • Genetic Defect: Most common cause.
  • Other Causes: Liver disease, chronic blood transfusions.
Clinical Manifestations
Early Symptoms
  • Fatigue
  • Joint pain (arthralgia)
  • Impotence
  • Abdominal pain
  • Weight loss
Late Symptoms
  • Liver enlargement due to excess iron accumulation
  • Cirrhosis of the liver
  • Bronzing of the skin
  • Heart disease (cardiomyopathy)
  • Right upper quadrant (RUQ) enlargement
Diagnostics and Treatment
Diagnostics
  • Increased iron levels (Fe)
  • Genetic testing
Complications
  • Liver failure
  • Cirrhosis
  • Liver cancer
  • Heart failure
Treatment
  • Remove excess iron through:
      - Phlebotomy (500 ml/week)
      - Iron chelating agents
      - Limiting Vitamin C, iron supplements, and iron-rich foods

Polycythemia

Definition
  • Polycythemia is characterized by the absolute increase in red blood cell (RBC) mass.
Types
Primary Polycythemia
  • Erythropoietin (EPO) levels are decreased or normal.
  • Example: Polycythemia vera (all blood cells elevated).
Secondary Polycythemia
  • EPO levels are increased due to:
      - Hypoxia-driven causes (high altitude, cardiopulmonary diseases, defective O2 transport, renal cysts or tumors)
      - Hypoxia-independent causes (extrarenal tumors)
  • Common mutation: Jak-2 mutation.
Complications and Clinical Manifestations
Complications
  • Stroke due to hyperviscosity and increased risk of thrombus formation.
  • Splenomegaly and hepatomegaly due to the accumulation of RBCs.
  • Bleeding disorders due to fragile platelets.
Clinical Manifestations
  • Hypertension (HTN)
  • Fatigue
  • Feeling of fullness
  • Pruritus: It worsens with a warm bath.
  • Painful burning and redness of hands and feet
      - Elevated hematocrit leading to thick blood (hyperviscosity)
      - Risk of thrombus formation
      - Overproduction of uric acid.
Diagnostics and Treatment
Diagnostics
  • Complete Blood Count (CBC) showing all blood cells elevated in primary vs. only RBC elevation in secondary polycythemia.
  • Bone marrow biopsy.
Treatment
  • Phlebotomy: Weekly until hematocrit is less than 45%, then every 2-3 months for life.
  • Medications:
      - Aspirin (ASA)
      - Hydroxyurea
      - Myelosuppressive medication to reduce RBCs and platelets.

Bleeding Disorders

Thrombocytopenia
Definition
  • Thrombocytopenia is defined as a decrease in platelet counts to below 150,000/uL.
  • Heparin-Induced Thrombocytopenia (HIT):
      - Occurs 5-14 days after initiating heparin therapy.
      - Affects 5% of patients on heparin, causing a reduction of platelet count by more than 50%.
Clinical Manifestations and Diagnostics
Clinical Manifestations
  • Epistaxis (nosebleeds)
  • Petechiae and purpura
  • Prolonged bleeding
  • Tachycardia
  • Hypotension
  • Decreased level of consciousness (LOC)
Diagnostics
  • CBC showing decreased platelet count below 150,000/uL.
  • Coagulation studies to assess bleeding function.
  • Bone marrow biopsy in some cases.
Heparin-Induced Thrombocytopenia (HIT)
Key Points
  • If history of HIT exists, the patient should not receive any heparin products again.
  • Care involves monitoring platelet count during therapy.
Treatment and Nursing Care for HIT
If HIT Occurs
  • Stop Heparin immediately.
  • Administer Protamine sulfate as a reversal agent for heparin.
  • Consider alternative anticoagulation options like Apixaban (direct thrombin inhibitor).
  • Platelet transfusion is considered based on risk/benefit (usually if platelet count is <10,000 unless active bleeding exists).

Math Example

Heparin Infusion Calculation
  • Order: Infuse heparin at 18 units/kg/hr.
  • Heparin bag: 25,000 units in 250 ml of 0.9% NS.
  • Patient weight: 180 lbs (approximately 81.65 kg). Adjust pump rate based on this calculation.

PTT Level Management

Levels
  • 30-44 sec: 40 units/kg bolus, increase rate by 2 units/kg/hr after 6 hours.
  • 46-65 sec: No bolus, no change.
  • 66-85 sec: No bolus, decrease rate by 1 unit/kg/hr.
  • >105 sec: No bolus; hold until PTT <90 sec.

Hemophilia

Definition
  • Hemophilia is an X-linked recessive disorder passed from mother to son, resulting in deficiency of clotting factors.
  • Types:
      - Hemophilia A: Factor VIII deficiency (factor VIII is produced in the liver).
Clinical Manifestations and Complications
Bleeding Symptoms
  • Any bleeding episode can be life-threatening.
  • Acute, prolonged, or delayed bleeding may occur hours to days after an injury.
Complications
  • Hemorrhage
  • Hemarthrosis (bleeding into joint spaces)
  • Nerve compression leading to pain and paralysis from distal bleeding.
Diagnostics
  • Deficiency of Factor VIII in blood tests.
  • Prolonged activated Partial Thromboplastin Time (aPTT).
  • Normal platelet count and prothrombin time (PT).
Treatment and Nursing Care
Prevention Strategies
  • Recommend non-contact sports and use of soft-bristled toothbrushes.
  • Use gloves during household chores.
  • Treat minor bleeding episodes for at least 72 hours.
  • DDAVP (desmopressin acetate):
      - Synthetic analog of vasopressin, can be administered IV, SC, or intranasally.
      - Stimulates release of factor VIII; effects evident within 30 mins and may last over 12 hours.
      - Possible need for repeated doses.
      - Patient should wear a Medic Alert bracelet.
Acute Care Strategies
  • Stop bleeding via direct pressure and topical thrombin agents.
  • Volume replacement with PRBC transfusions and IV fluids (IVFs).
  • Administer DDAVP IV – effects noted within 30 minutes and lasting for about 12 hours.
  • Follow RICE protocol for management of joint swelling: Rest, Ice, Compress, Elevate.
      - Avoid NSAIDs.

Disseminated Intravascular Coagulation (DIC)

Definition
  • DIC is not a distinct disease but a complication caused by an underlying disease or condition. It results in serious bleeding and thrombotic disorders due to abnormally initiated and accelerated clotting.
Risk Factors
  • Trauma
  • Sepsis
  • Pregnancy
Pathophysiology
  • Triggering of abnormal response of the clotting cascade, causing excessive fibrin and platelet aggregation that leads to thrombosis and subsequent depletion of clotting factors, resulting in bleeding.
Events Leading to Thrombosis and Bleeding
Thrombotic Events
  • Activation of coagulation cascade leading to thrombotic occlusion of microcirculation across all organs.
  • Fibrinolysis in the microcirculation leads to circulating fibrin degradation products.
Bleeding Events
  • Consumption of platelets and coagulation proteins.
  • Signs of thrombosis can include delirium, coma (neurological), ischemia and gangrene (integumentary), oliguria and azotemia (renal), and ECG changes (cardiovascular).
Clinical Manifestations
  • Bleeding Signs: Petechiae, purpura, ecchymosis, bleeding from venipuncture sites, increased respiratory rate and shortness of air, hemoptysis, decreased blood pressure, increased heart rate, GI bleeding, GU bleeding.
  • Thrombotic Signs: Increased respiratory rate and dyspnea, ischemia, cyanosis, tissue necrosis, oliguria, and venous distention.
Diagnostics and Treatment
Diagnostics
  • Prolonged PT, PTT, and aPTT.
  • Decreased platelet count and fibrinogen levels.
  • D-dimer blood tests to identify blood clotting issues.
Treatment
  • Provide oxygenation and volume replacement with Fresh Frozen Plasma (FFP) and platelets if there is significant bleeding or prolonged bleeding time.
  • Critical to treat the underlying cause, as DIC is a complication rather than a standalone disease.

Learning Checks

Scenario 1: Thrombocytopenia
  • Which lab value is consistent with diagnosis: B. Platelet count of 120,000.
Scenario 2: Hemophilia
  • Prioritize nursing intervention for a client with severe hemarthrosis: C. Rest the affected extremity.