Hematology Basics Quiz

Hematologic Disorders: Assessment and Management

• The hematologic system includes blood and its production sites (bone marrow, reticuloendothelial system).
• Blood comprises plasma (55%), and blood cells (RBCs, WBCs, platelets) (45%).

Hematopoiesis

• Red blood cells (RBCs) are produced in bone marrow as reticulocytes, carrying oxygen via hemoglobin; lifespan ~120 days
• White blood cells (WBCs), divided into granulocytes and lymphocytes, fight infection, and engage in phagocytosis and immune responses
• Platelets (thrombocytes) are cell fragments essential for coagulation and hemostasis; lifespan ~10 days

Assessment and Diagnostic Evaluation

• History & physical exam are initial assessments
• Complete blood count (CBC) is a common initial test assessing RBCs, WBCs, platelets, hemoglobin, and hematocrit.
• Erythrocyte sedimentation rate (ESR) and coagulation tests (PT, PTT, INR) evaluate specific aspects of blood function.
• Bone marrow aspiration/biopsy assess blood cell production and potential infection/tumour.
• Bone marrow is usually obtained from the iliac crest or sternum

Bone Marrow Aspiration/Biopsy Procedure

• Patient preparation involves explanation, potential anxiety management (medication), informed consent.
• Procedure involves deep breaths or relaxation techniques.
• Potential complications include bleeding and infection; pressure & sterile dressing are applied post-procedure.
• Mild discomfort (ache) at biopsy site for 1-2 days is common; aspirin-containing analgesics should be avoided postprocedure.

Anemia

• Anemia is a condition where hemoglobin levels are lower than normal, reducing oxygen delivery to tissues.
• It's a symptom, not a disease, and various underlying causes exist.
• It's the most common hematologic disorder.

Classification of Anemia

• Hypo-proliferative: Inadequate RBC production due to marrow damage (medications, chemicals) or lack of essential factors (iron, vitamin B12, folic acid, erythropoietin).
• Bleeding: Results from loss of RBCs due to various causes.
• Hemolytic: RBC destruction, releasing hemoglobin into plasma. Increased bilirubin, erythropoietin production (increased reticulocyte count).
  • Intracellular (e.g., sickle cell disease, G-6-PD deficiency)
  • Plasma-related (e.g., immune hemolytic anemias)
  • Direct injury (e.g., mechanical heart valve)

Iron Deficiency Anemia

• Caused by insufficient dietary iron, inadequate iron stores, or blood loss.
• Causes include ulcers, gastritis, inflammatory bowel disease, menorrhagia, pregnancy (without supplementation), chronic alcoholism, iron malabsorption (post-surgery, celiac/IBD).
• Clinical Manifestations: Fatigue, weakness, pallor, tachycardia, palpitations, dyspnea, nausea, vomiting, melena (dark stools), diarrhea, anorexia, glossitis, pica (craving non-food items) and potential symptoms of a smooth, red tongue, brittle/ridged nails, and angular cheilosis.
• Assessment: Bone marrow aspiration, low hematocrit, RBC, hemoglobin, and ferritin values.
• Medical Management: Identify and address the cause, oral iron supplements (ferrous sulfate, ferrous gluconate), potentially IV/IM iron dextran (if oral ineffective/poorly tolerated) with a small test dose and monitoring, long-term iron therapy (~6-12 months).

Sickle Cell Anemia

• Hereditary, often from consanguineous marriage
• Defective hemoglobin (HbS) causes rigid, sickle-shaped RBCs, impairing blood flow.
• Clinical Manifestations: Jaundice (especially sclera), low hemoglobin (5-11 g/dL), potential bone marrow expansion, tachycardia, cardiomegaly, dysrhythmias, heart failure. Complications include infections, stroke, kidney injury, impotence, heart failure, pulmonary hypertension.
• Sickle Cell Crisis: Three types:
  • Acute vaso-occlusive crisis: Microcirculation blockage, tissue hypoxia, inflammation, necrosis.
  • Aplastic crisis: Parvovirus infection, rapid hemoglobin drop, lack of reticulocytes.
  • Sequestration crisis: Sickled cells pooled in spleen (children), liver/lung (adults).
• Risk factors include dehydration, cold exposure, stress, strenuous activity, infection, low oxygen tension.
• Acute Chest Syndrome: Respiratory distress, fever, new chest x-ray infiltrates (leading cause of death in young adults). Often associated with infection, fat embolism, infarction, thromboembolism, or bone marrow embolism. Requires aggressive RBC transfusion and antibiotic therapy; mechanical ventilation may be necessary.
• Pulmonary Hypertension: Frequent complication, often a cause of death. Patients may present with fatigue, exertional dyspnea, dizziness, chest pain, or syncope, but pulse oximetry & breath sounds may be normal initially. Doppler echocardiography screening may identify elevated pulmonary artery pressure.
• Stroke: Common in younger patients; decreased cerebral blood flow due to anemia, hemolysis, and hypoxic stress. Tx includes RBC transfusions to reduce HbS below 30% and prevent cerebral edema.

Thalassemia

• Hereditary anemias causing hypochromia, microcytosis, hemolysis, and variable anemia.
• Defective hemoglobin synthesis with reduced globulin chain production.
• Reduced hemoglobin causes premature RBC destruction.
• Classification: Alpha (milder) and Beta (variant severity, including Thalassemia major/Cooley's anemia, often fatal in early childhood if untreated).
• Management: Possible PBSCT, RBC transfusions, iron chelation therapy.
• Thalassemia Major: Severe anemia, hemolysis, ineffective erythropoiesis; transfusion therapy improves growth/development; iron overload complications necessitate chelation therapy. Late complications include neurologic complications (cognitive dysfunction, peripheral neuropathy, cerebrovascular disease).

Overall Management and Nursing Care

• Nursing Interventions: Managing pain and fatigue, infection prevention, coping skill promotion, and knowledge deficit. Pain management may involve aspirin, NSAIDs, or parenteral opioids, alongside nonpharmacological approaches like physical therapy, cognitive behavioral therapy, and support groups (for chronic pain).
• Fluid and Preventative Measures: Adequate hydration during sickle cell crises.
• Education for Prevention: Maintaining adequate hydration, avoiding cold, stress, strenuous activity, or infection is critical for reducing crisis frequency.