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NR 324 – Red Blood Cell & Anemia Disorders Vocabulary

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RBCs Anemia (General)

Etiology / Pathophysiology

  • Definition: A quantitative or qualitative reduction in circulating red blood cells (RBCs) or hemoglobin (Hgb) resulting in diminished oxygen‐carrying capacity.
  • Mechanistic routes:
    1. Blood-loss anemia (acute or chronic)
    2. Decreased production of RBCs / Hgb by the bone marrow
    3. Increased destruction (hemolysis) of circulating RBCs
  • Physiologic impact: ↓ tissue oxygenation → compensatory tachycardia & increased cardiac output; redistribution of blood flow to vital organs.

Clinical Manifestations

  • General fatigue & weakness
  • Pallor of skin / mucous membranes
  • Dyspnea or shortness of breath, especially on exertion
  • Dizziness, light-headedness, possible orthostatic hypotension
  • Tachycardia, palpitations; possible systolic murmur
  • Cold intolerance (cold hands & feet)

Diagnostic Tests

  • Complete blood count (CBC): ↓ \text{Hgb} & \text{Hct}; may note altered \text{MCV} & \text{MCHC} depending on type.
  • Reticulocyte count (reflects marrow response)
  • Iron studies, serum \text{B}_{12}, folate if etiology unclear.

Nursing Interventions / Collaborative Management

  • Identify & correct underlying cause.
  • Monitor vital signs; supplemental oxygen if \text{SpO}_2< 92\%.
  • Energy-conservation strategies; cluster nursing activities.
  • Nutrition teaching: iron, folate, \text{B}_{12} rich foods.
  • Facilitate blood transfusion or pharmacologic therapy when ordered.

Potential Complications & Management

  • High-output heart failure or angina (myocardial hypoxia)
  • Severe tissue hypoxia → organ dysfunction
  • Interventions: PRBC transfusion, pharmacologic support, treat precipitating disease.

Chronic Anemia / Chronic Blood Loss

Etiology / Pathophysiology

  • Slow, continuous blood loss (e.g., peptic ulcer, colorectal cancer, heavy menses) → gradual iron depletion & ↓ RBC mass.
  • Bone marrow can partially compensate, masking symptoms until stores are exhausted.

Clinical Manifestations

  • Progressive fatigue, exertional dyspnea
  • Pallor & cool extremities
  • Dizziness that worsens with activity or position change

Diagnostic Tests

  • CBC: normocytic initially → microcytic/hypochromic once iron deficit ensues.
  • Iron studies (↓ serum iron & ferritin, ↑ TIBC)
  • Stool guaiac / FIT, endoscopy, colonoscopy to locate bleeding source.

Nursing Interventions / Collaborative Management

  • Quantify & monitor overt/occult bleeding; hemodynamic trends.
  • Oral or IV iron therapy; PRBC transfusion if symptomatic \text{Hgb} < 7\,\text{g/dL} (institutional policy).
  • Coordinate diagnostic procedures to identify & treat bleed (e.g., GI lab, gynecology).

Possible Complications & Treatment

  • Severe anemia → hypovolemic shock.
  • Immediate fluid resuscitation, transfusion, endoscopic or surgical hemostasis.

Iron-Deficiency Anemia (IDA)

Etiology / Pathophysiology

  • Inadequate iron supply for hemoglobin synthesis.
  • Causes: poor dietary intake, chronic bleeding (menorrhagia, GI), malabsorption (celiac, bariatric surgery), pregnancy demands.
  • Result: Production of microcytic, hypochromic RBCs with ↓ oxygen capacity.

Clinical Manifestations

  • Classic anemia symptoms plus:
    • Brittle, spoon-shaped nails (koilonychia)
    • Glossitis (inflamed sore tongue)
    • Angular cheilitis
    • Pica (craving ice, dirt, starch)

Diagnostic Tests (see also Page 2)

  • CBC: ↓ Hgb, ↓ Hct, ↓ MCV (<80\,\text{fL})
  • Iron panel: ↓ serum iron, ↓ ferritin, ↑ TIBC (total iron-binding capacity)

Nursing Interventions / Collaborative Management

  • Oral ferrous sulfate 325\,\text{mg} TID between meals with vitamin C.
  • For malabsorption/intolerance: IV iron sucrose or ferric carboxymaltose using test dose precautions (anaphylaxis risk).
  • Teach iron-rich foods: red meat, liver, spinach, legumes; avoid tea/coffee with meals.

Possible Complications & Treatment

  • Chronic IDA → cardiopulmonary strain, adverse pregnancy outcomes (pre-term, low birth weight).
  • Long-term iron repletion & correction of bleeding source.

Page 2

Iron-Deficiency Anemia (continued)

  • High TIBC is a compensatory hepatic response to ↓ transferrin saturation → distinguishes IDA from anemia of chronic disease (which shows low TIBC).
  • Ethical / real-world note: IDA disproportionately affects low-income & food-insecure populations → advocate for nutrition programs.

Thalassemia

Etiology / Pathophysiology

  • Autosomal-recessive mutations causing impaired production of either α- or β-globin chains → unbalanced globin synthesis, ineffective erythropoiesis, hemolysis.
  • Prevalence: Mediterranean, Middle Eastern, South Asian. Carrier screening important (ethical counseling).

Clinical Manifestations

  • Spectrum: asymptomatic trait → severe transfusion-dependent anemia.
  • Key signs: growth retardation, bone marrow expansion causing facial bone deformities (chipmunk facies), dark urine (hemoglobinuria), splenomegaly from extravascular hemolysis.

Diagnostic Tests

  • CBC: severe microcytosis with disproportionately low MCV vs. Hgb.
  • Hemoglobin electrophoresis: elevated \text{HbF} or \text{HbA}_2; presence of abnormal Hb pattern.
  • Genetic testing for definitive α/β gene deletions or point mutations.

Nursing Interventions / Collaborative Management

  • Regular transfusion schedule to keep \text{Hgb} > 10\,\text{g/dL} → prevents skeletal deformity & growth delay.
  • Folic acid 1 mg daily to support erythropoiesis.
  • DO NOT give iron unless laboratory-proven deficiency.
  • Psychosocial & genetic counseling for family planning.

Possible Complications & Treatment

  • Iron overload from repeated transfusions → cardiomyopathy, liver cirrhosis, endocrine failure.
  • Chelation: deferoxamine (parenteral), deferasirox or deferiprone (oral).
  • Curative option: hematopoietic stem cell transplant (best in childhood).

Vitamin B₁₂ Deficiency (Megaloblastic Anemia)

Etiology / Pathophysiology

  • Vitamin B₁₂ is cofactor for DNA synthesis & neurologic myelination. Lack leads to impaired nucleus maturation → macrocytic (megaloblastic) RBCs.
  • Causes: pernicious anemia (autoimmune destruction of gastric parietal cells → intrinsic factor deficiency), strict vegan diet, gastrectomy, Crohn’s disease, proton-pump inhibitor overuse.

Clinical Manifestations

  • Standard anemia symptoms + symmetric paresthesias (hands/feet), ataxia, decreased proprioception, cognitive changes (memory loss, depression).

Diagnostic Tests

  • CBC: ↑ MCV (macrocytosis, >100\,\text{fL}).
  • ↓ serum B₁₂ (<200\,\text{pg/mL}).
  • Positive anti-intrinsic factor or anti-parietal cell antibodies.
  • Classic Schilling test historically measured B₁₂ absorption with/without intrinsic factor.

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Nursing Interventions / Collaborative Management

  • Parenteral cyanocobalamin 1000\,\mu\text{g} IM monthly for pernicious anemia (lifelong).
  • High-dose oral B₁₂ (if intact absorption pathway).
  • Monitor neurologic status; fall precautions, physical therapy referral.

Possible Complications & Treatment

  • Prolonged deficiency → irreversible spinal cord demyelination; treat promptly.

Folic Acid Deficiency

Etiology / Pathophysiology

  • Folate required for purine/pyrimidine synthesis; deficiency arises from poor diet, alcoholism (↓ intestinal absorption & ↑ urinary loss), malabsorption syndromes, increased demand (pregnancy), medications (methotrexate, phenytoin).

Clinical Manifestations

  • Similar to B₁₂ deficiency without neurologic signs. Smooth, beefy-red tongue (glossitis).

Diagnostic Tests

  • CBC: macrocytosis.
  • ↓ serum folate (<4\,\text{ng/mL}) with normal B₁₂.

Nursing Interventions / Collaborative Management

  • Oral folic acid 1–5\,\text{mg} daily.
  • Encourage folate-rich foods: leafy greens, citrus, legumes, fortified grains.
  • If drug-induced, discuss alternatives with provider.

Possible Complications & Treatment

  • Maternal folate deficiency → neural tube defects (ethical imperative: prenatal supplementation 400\,\mu\text{g/day}).
  • Chronic anemia-related fatigue; treat with replacement therapy.

Aplastic Anemia

Etiology / Pathophysiology

  • Bone marrow stem-cell failure → pancytopenia (↓ RBC, WBC, platelets).
  • Triggers: idiopathic autoimmune, benzene, chloramphenicol, viral (hepatitis, HIV), radiation/chemotherapy.

Clinical Manifestations

  • Symptoms correspond to cytopenias:
    • Anemia → fatigue, dyspnea
    • Leukopenia → recurrent infections, fevers
    • Thrombocytopenia → petechiae, mucosal bleeding, bruising

Diagnostic Tests

  • CBC: all cell lines reduced, \text{retic\%} low.
  • Bone marrow biopsy: hypocellular/fatty marrow.

Nursing Interventions / Collaborative Management

  • Protective isolation; strict hand hygiene.
  • Avoid IM injections/venipuncture when possible; use soft toothbrush, electric razor.
  • Transfusion support (PRBCs, platelets).
  • Administer immunosuppressants (ATG, cyclosporine) or promote transplant work-up.

Possible Complications & Treatment

  • Sepsis, fatal hemorrhage.
  • Curative: matched sibling hematopoietic stem cell transplant; otherwise long-term immunosuppression & supportive care.

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Sickle Cell Disease (SCD)

Etiology / Pathophysiology

  • Point mutation (Glu➔Val) on β-globin → hemoglobin S (\text{HbS}). Under hypoxia, \text{HbS} polymerizes, causing RBC sickling, rigidity, hemolysis & microvascular occlusion.
  • Homozygous \text{HbSS} most severe; heterozygous (trait) usually asymptomatic but important for genetic counseling.

Clinical Manifestations

  • Vaso-occlusive pain crises (bones, chest, abdomen).
  • Dactylitis (hand-foot swelling) in children.
  • Chronic anemia & jaundice.
  • Delayed growth & puberty, priapism, leg ulcers, retinopathy.

Diagnostic Tests

  • Newborn screening (isoelectric focusing).
  • Hemoglobin electrophoresis confirms \text{HbS} proportion.
  • Peripheral smear: sickled cells, target cells, Howell-Jolly bodies (if asplenia).

Nursing Interventions / Collaborative Management

  • HOP strategy during crisis: Hydration, Oxygenation, Pain control (IV opioids).
  • Maintain fluid intake >3\,\text{L/day}; avoid extremes of temperature, high altitude.
  • Prophylactic penicillin & immunizations to prevent infection.
  • Hydroxyurea increases \text{HbF}, reducing crises frequency.
  • Folic acid 1 mg/day for erythropoiesis.

Possible Complications & Treatment

  • Acute chest syndrome (pulmonary vaso-occlusion), stroke, splenic sequestration, renal papillary necrosis.
  • Exchange transfusion for acute chest/stroke; chronic transfusion program for stroke prevention.
  • Curative: matched sibling stem cell transplant or gene therapy (investigational, ethical considerations for access).

Hemolytic Anemia (Acquired / Inherited)

Etiology / Pathophysiology

  • Premature RBC destruction → ↑ erythropoietic demand.
  • Causes: warm or cold autoimmune hemolysis, infections (malaria), drugs (penicillin, quinidine), hereditary spherocytosis, G6PD deficiency.

Clinical Manifestations

  • Anemia symptoms + jaundice, dark cola-colored urine (hemoglobinuria), splenomegaly.

Diagnostic Tests

  • CBC: normocytic anemia with ↑ reticulocytes.
  • Biochem: ↑ indirect bilirubin, ↓ haptoglobin.
  • Direct Coombs (DAT) positive if autoimmune.
  • Peripheral smear: spherocytes, schistocytes depending on cause.

Nursing Interventions / Collaborative Management

  • Treat precipitating factor (stop offending drug, treat infection).
  • If autoimmune: high-dose corticosteroids, IVIG, rituximab; plasmapheresis for severe cases.
  • Splenectomy in refractory hemolysis.

Possible Complications & Treatment

  • Gallstones (pigmented), heart failure crises.
  • Long-term monitoring for iron overload if transfusion-dependent.

Polycythemia

Etiology / Pathophysiology

  • Excessive RBC mass → hyperviscosity, sluggish circulation.
  • Primary: Polycythemia vera (JAK2 V617F mutation → autonomous marrow proliferation).
  • Secondary: chronic hypoxia (COPD, congenital heart disease), high altitude, EPO-secreting tumors (renal cell carcinoma).

Clinical Manifestations

  • Hypervolemic symptoms: headache, dizziness, blurred vision.
  • Aquagenic pruritus (itching after hot shower).
  • Facial plethora (ruddy complexion), hypertension.
  • Thrombotic events: DVT, PE, CVA, MI.

Diagnostic Tests

  • CBC: ↑ RBC, Hct (>52\% males, >48\% females), ↑ Hgb.
  • Serum erythropoietin: low in PV, high in secondary polycythemia.
  • Bone marrow biopsy: hypercellularity; JAK2 mutation testing.

Nursing Interventions / Collaborative Management

  • Scheduled phlebotomy: remove 300–500\,\text{mL} blood until Hct <45\%.
  • Encourage hydration to ↓ viscosity.
  • Low-dose aspirin (81 mg) unless contraindicated.
  • Educate on smoking cessation, avoiding iron supplementation (stimulates erythropoiesis).

Possible Complications & Treatment

  • Major arterial/venous thrombosis, hemorrhage (due to dysfunctional platelets), myelofibrosis/leukemia transformation.
  • Cytoreductive therapy (hydroxyurea, interferon-α) for high-risk patients.

Ethical, Philosophical & Real-World Connections

  • Health disparities: SCD & thalassemia predominantly affect specific ethnic groups; equitable access to advanced therapies (e.g., gene therapy, HSCT) is a social justice issue.
  • Chronic transfusion programs raise concerns about alloimmunization and resource allocation.
  • Nutritional anemias often mirror socioeconomic inequities; nurses play a key advocacy role in community outreach and policy.

Cross-Lecture / Foundational Integration

  • Link to physiology: Oxygen-hemoglobin dissociation curve; anemia shifts curve & impairs oxygen release.
  • Pharmacology tie-in: Hydroxyurea (S-phase specific, increases \text{HbF}); chelators’ renal/hepatic monitoring.
  • Pathology correlation: Hemolysis elevates LDH & bilirubin; understanding lab panels enhances diagnostic reasoning.

Quick Reference – Normal Lab Ranges (for comparison)

  • \text{Hgb}: 13.5–17.5 g/dL (♂), 12–15.5 g/dL (♀)
  • \text{Hct}: 41–53 % (♂), 36–46 % (♀)
  • \text{MCV}: 80–100 fL
  • Serum ferritin: 30–400 ng/mL (♂), 15–150 ng/mL (♀)
  • Serum B₁₂: 200–900 pg/mL
  • Serum folate: 4–20 ng/mL

These values provide context for interpreting the diagnostic tables above and connecting to laboratory medicine discussions.