RC

Hematology: Assessment & Patient Care – Comprehensive Exam Notes

Hematologic System Assessment (Chapter 33)

Priority Concepts

  • Ability to transport O2 and CO2
  • Maintenance of coagulation & intravascular volume
  • Protection against infection

Anatomy & Physiology Review

Bone Marrow – Primary Site of Hematopoiesis

  • Continuously produces:
    • \text{RBCs (erythrocytes)}
    • \text{WBCs (leukocytes)}
    • \text{Platelets (thrombocytes)}
  • FUN FACT: Daily marrow release per kg body weight
    • 2.5 \times 10^{9} RBCs
    • 2.5 \times 10^{9} Platelets
    • 1 \times 10^{9} WBCs
  • Clinical significance: Any marrow failure → pancytopenia, hypoxia, bleeding, infection risk

Blood Components

  • Plasma proteins
    • Albumin – maintains oncotic pressure
    • Globulins – transport & immunity (antibodies)
    • Fibrinogen – precursor to fibrin in clotting cascade
  • Cellular elements
    • RBCs: gas transport
    • WBCs: immune defense
    • Platelets: primary hemostasis

Accessory Organs of Blood Formation

  • Spleen – filters old/defective cells, houses lymphocytes, stores platelets
  • Liver – produces clotting factors, stores iron, conjugates bilirubin

Hemostasis & Blood-Clotting Sequence

  1. Vessel injury → transient vasoconstriction
  2. Platelet adhesion & aggregation → platelet plug
  3. Activation of coagulation cascade → conversion of fibrinogen to fibrin → stable clot

Anticlotting (Fibrinolytic) Forces

  • Plasminogen → plasmin → dissolves fibrin
  • Deficiency of any natural anticoagulant (protein C, protein S, antithrombin) ↑ thrombosis risk

Hematologic Changes Associated with Aging

  • ↓ Total blood volume
  • Marrow produces fewer cells ⇒ ↓ \text{RBC}, ↓ \text{WBC} counts
  • Lymphocytes less responsive ⇒ weaker immune responses
  • Hb falls after middle age (esp. in women post-menopause)
  • Clinical pearl: fatigue & infection in elders may reflect normal aging OR occult pathology

Comprehensive Patient Assessment

  • Demographics: age, gender (e.g., menstruation-related iron loss)
  • Liver function history (clotting factor synthesis)
  • Medication review: anticoagulants, NSAIDs, chemo, herbals (ginkgo, garlic)
  • Diet: iron, B₁₂, folate, protein intake
  • Socio-economic factors: food security, insurance, toxin exposure
  • Radiation history: past cancer therapy → marrow dysplasia risk
  • Occupation/hobbies: chemicals, pesticides, solvents, lead, benzene
  • Home location: altitude (chronic hypoxia), industrial pollutants
  • Family/genetic disorders: hemophilia, sickle cell, thalassemia
  • Current symptoms: bleeding, bruising, fatigue, infections, weight loss

Laboratory & Diagnostic Panel (pg 708-712)

  • Coagulation/bleeding studies
    • \text{D-dimer} – fibrin degradation; ↑ = active clot breakdown (DVT/PE suspicion)
    • \text{PT} (Prothrombin Time) – extrinsic pathway; therapeutic target in warfarin therapy
    • \text{INR} – normalized PT (goal 2.0–3.0 for most indications)
    • \text{aPTT} – intrinsic pathway; monitors IV heparin (goal 1.5–2.5 × control)
  • Imaging: ultrasound (DVT), CT (splenomegaly), bone scan
  • Bone-marrow aspiration/biopsy – definitive for dyscrasias

Care of Patients with Hematologic Problems (Chapter 34)

Priority Concepts

  • Perfusion → Sickle Cell Disease (SCD)
  • Immunity → Leukemia

Disorders of Erythrocytes

Sickle Cell Disease – Destruction of RBCs

  • Genetic mutation → abnormal HbS chains
  • Deoxygenation, dehydration, acidosis → polymerization → "sickling"
  • Sickled cells:
    • Rigid, sticky, obstruct capillaries → ischemia, pain crises
    • Short lifespan ⇒ chronic hemolytic anemia
  • Epidemiology: common in African-Americans; protective vs. malaria
Assessment
  • Severe pain = hallmark (ischemic tissue injury)
  • Chronic anemia symptoms: fatigue, pallor, jaundice (↑ bilirubin)
  • Multi-system effects (Fig 34.4):
    • CVA, acute chest syndrome, splenic sequestration, renal failure, priapism, ulcers
  • Pain undertreatment common; tolerance necessitates higher opioid doses
Treatment – "HOP to it"
  • Hydration: isotonic IV fluids (e.g., 0.9\% NS) to ↓ blood viscosity
  • Oxygenation: prevents further sickling
  • Pain relief: IV opioids (morphine, hydromorphone)
  • Drug therapy: hydroxyurea ↑ HbF, L-glutamine, transfusions, crizanlizumab; stem-cell transplant = curative in selected pts

Anemias r/t Decreased Production

  • Defined by ↓ number of RBCs, ↓ Hb, or ↓ hematocrit
  • Not a disease itself; indicator of underlying issue (nutritional, marrow, chronic disease)

Polycythemia Vera – Excess RBC Production

  • Chronic myeloproliferative neoplasm (JAK2 mutation)
  • ↑ RBC mass → hypervolemia + hyperviscosity
  • Clinical picture:
    • Ruddy/cyanotic mucosa & facial skin (venous stasis)
    • Splenomegaly, pruritus, gout, thrombosis risk
    • End-organ damage (heart, spleen, kidneys)
  • Tx: phlebotomy (target Hct <45\%), hydration, low-dose aspirin, cytoreductive drugs (hydroxyurea)

Hereditary Hemochromatosis – Excess Iron

  • Autosomal-recessive (HFE gene) → ↑ intestinal iron absorption
  • Iron deposition damages liver, pancreas, heart, joints, skin ("bronze diabetes")
  • Dx: ↑ serum ferritin & transferrin saturation
  • Tx: serial phlebotomy, deferasirox/deferoxamine if needed, limit iron & vitamin C intake

Disorders of Leukocytes

Leukemia – Uncontrolled Immature WBC Proliferation

  • Loss of normal cellular regulation → accumulation of "blast" cells in marrow, blood, tissues
  • Results in:
    • Anemia (↓ RBC)
    • Infection (non-functional WBC)
    • Bleeding (↓ platelets)
  • Can be acute vs. chronic; myeloid vs. lymphoid
  • Etiology: multifactorial – oncogene activation, chemo/radiation, viruses, pesticides, smoking, congenital disorders (Down syndrome)
Assessment / Labs
  • CBC: ↓ Hb & Hct, thrombocytopenia
  • WBC count may be ↓, normal, or ↑ but with high percentage of blasts
  • Bone-marrow aspiration/biopsy = diagnostic gold standard
  • Other: lumbar puncture (CNS involvement), cytogenetics (e.g., Philadelphia chromosome)
Classification (Table 34.25)
  • AML – \approx 80\% of adult acute cases (>60 yrs)
  • ALL – \approx 20\% of adult acute cases (>50 yrs)
  • CML – \approx 20\% chronic adult cases; median 67 yrs; Ph+; phases (chronic ⇒ accelerated ⇒ blast)
  • CLL – Most common adult leukemia; avg onset 72 yrs; B-cell origin
Treatment & Nursing Interventions
  • Combination chemotherapy (induction, consolidation, maintenance)
  • Corticosteroids, targeted therapy (imatinib for CML), radiation (CNS prophylaxis)
  • Hematopoietic stem-cell transplantation (HSCT) – potential cure
  • Supportive: infection prophylaxis, transfusions, psychosocial support

Coagulation Disorders

Thrombocytopenia – Platelets <150{,}000/\mu L

  • Can be acute, severe, prolonged
  • Bleeding risks: mucosal, cutaneous, intracranial
Immune Thrombocytopenia (ITP)
  • Autoantibody-mediated platelet destruction & splenic sequestration
  • Acute in kids; chronic in adults
  • Tx: corticosteroids, IVIG, splenectomy, rituximab, eltrombopag (TPO agonist)
Heparin-Induced Thrombocytopenia (HIT)
  • Onset 5–14 days after heparin initiation (sooner if prior exposure)
  • Pathophysiology: IgG antibodies vs. PF4-heparin complex → platelet activation → paradoxical thrombosis
  • Up to 5\% of IV heparin pts
  • Management: stop heparin, start non-heparin anticoagulant (argatroban), avoid platelet transfusion unless life-threatening bleed

Hemophilia – Hereditary Factor Deficiency

  • X-linked recessive → males affected, females carriers
  • Types:
    • Hemophilia A – Factor VIII deficiency ("classic"); 4× more common
    • Hemophilia B – Factor IX deficiency ("Christmas disease")
  • Clinical manifestations identical:
    • Prolonged bleeding, hematomas, hemarthrosis (joint bleeding), GI bleed, intracranial hemorrhage
  • Any bleeding episode can be fatal
Diagnosis (Table 34.17)
  • Coagulation studies: prolonged aPTT; normal PT & platelets
  • Factor assays quantify specific factor activity
Treatment (Table 34.18)
  • Factor replacement (recombinant VIII or IX) – on demand or prophylactic
  • Desmopressin (DDAVP) for mild Hemophilia A (releases endogenous factor VIII)
  • Antifibrinolytics: tranexamic acid for mucosal bleeding
  • Gene therapy trials emerging
Nursing Care
  • Prevent trauma: safe environment, protective gear, avoid contact sports
  • No IM injections or ASA/NSAIDs; use acetaminophen
  • Educate on bleeding recognition & self-infusion techniques
  • During bleed: immobilize joint, ice, elevate, give factor, then PT once swelling ↓

Ethical, Philosophical & Practical Considerations

  • Health disparities: SCD pain bias & under-treatment highlight systemic inequities
  • Genetic counseling: imperative for hereditary disorders (SCD, hemophilia, hemochromatosis)
  • Resource allocation: HSCT accessibility, high-cost biologics
  • Occupational/environmental justice: pesticide exposure & leukemia risk in farmworkers
  • End-of-life discussions: aggressive leukemias with poor prognosis