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