Hematology & Oncology Comprehensive Notes first video

Circulatory System Fundamentals

• Directional Flow
  • Arteries ➜ carry blood away from the heart.
  • Veins ➜ return blood to the heart.
  • Capillaries ➜ microscopic, interwoven vessels where nutrient/waste exchange occurs and venous return begins.

Cellular & Plasma Elements of Blood

• Red Blood Cells (RBC / Erythrocytes)
  • Primary job: transport O2 to tissues & carry CO2 away.
  • Normal lifespan ≈ 120\ \text{days} in healthy adults.
• White Blood Cells (WBC / Leukocytes) ➜ immune surveillance & infection control.
• Platelets (Thrombocytes) ➜ initiate coagulation cascade & help form clots.

Thrombo-Embolic Disorders

• Pathophysiology: clot formation may follow vascular injury, endothelial "flaking", trauma or hyper-coagulable states. Obstruction → tissue ischemia/necrosis.
• Clinical Emergencies & Hallmark Signs
  • Pulmonary Embolism (PE):
    • Sudden dyspnea
    • Tachycardia
    • Hemoptysis
    • “Impending doom” sensation; can mimic pneumonia/back spasm.
  • Myocardial Infarction (MI):
    • Chest pain/pressure
    • Dyspnea
    • Diaphoresis
  • Stroke (CVA): FAST mnemonic
    • Facial droop
    • Arm weakness
    • Speech changes ± severe headache
    • Time = call 911.
  • Deep-Vein Thrombosis (DVT): unilateral extremity pain, swelling, redness, warmth.

Diagnostic Toolkit

• D\text{-dimer} (screening, not diagnostic) – if elevated seek clot.
• Venous Doppler ultrasound ➜ leg clot mapping.
• CT (head or chest, ± contrast) ➜ stroke/PE localization.

Anticoagulant & Antiplatelet Pharmacology

• Warfarin
  • Oral, taken same time daily.
  • Target \text{INR}=2\text{–}3.
  • Stop pre-op; bridge w/ LMWH (Lovenox) or Heparin until therapeutic.
• Apixaban (Eliquis): oral, BID.
• Enoxaparin (Lovenox): sub-q LMWH.
• Heparin: sub-q prophylaxis or IV infusion for acute clot; titrate via \text{aPTT}.
• Clopidogrel (Plavix): once-daily antiplatelet post-stent.
• Aspirin (OTC): GI upset, tinnitus, bleeding risk.

Deep Vein Thrombosis (DVT)

• Epidemiology: most frequent clot location—large veins of lower limbs.
• Major Risk Windows
  • Recent surgery, immobility (plane/car rides), malignancy.
• Assessment: Doppler ultrasound → size/extent; contrast venography for complex mapping.

Hemorrhage & Hypovolemia

• Adults tolerate ≈ 14\% blood-volume loss before instability.
• Risk Factors: anticoagulants, coagulopathies, trauma (MVC, falls, PPH).
• Presentation: nausea, clammy skin, tachycardia/pnea; may spiral to hypovolemic shock/coma if uncontrolled.
• Internal Bleed Clues
  • Hemoptysis / hematochezia
  • Rigid abdomen (intra-abdominal)
  • Neuro changes → confusion ➜ seizures ➜ LOC (intracranial).
• Work-up: CBC, PT/INR, aPTT, imaging (CXR, CT) to localize source.

Anemia – General Concepts

• Definition: insufficient hemoglobin to meet physiologic demand.
• Three classic etiologies
  1. Iron deficiency
  2. Vitamin B12 deficiency
  3. Folic-acid deficiency

Iron-Deficiency Anemia

• Most common worldwide. Iron required for Hb synthesis → low iron = low Hb.
• Symptoms: pallor, cold intolerance, SOB, hypotension, tachycardia, brittle nails/hair.
• Lab Hallmarks
  • \text{Hb}<13\ \text{g/dL (male)},\ <12\ \text{g/dL (female)}.
  • ↓ Ferritin (body iron stores).
  • \text{TIBC} assesses available binding sites.
  • ↑ Reticulocyte % if marrow compensating.
  • Stool guaiac ➜ occult GI loss; bone-marrow biopsy if etiology unclear.
• Dietary Management
  • Heme iron (animal) absorbed faster than non-heme (plant).
  • Vegetarians need higher intake or supplementation.
• Oral Iron Therapy
  • Empty stomach + Vitamin C (e.g., OJ) to boost absorption.
  • Major SE: constipation → counsel on fiber/fluids ± stool softener.

Vitamin B12 (*Cobalamin*) Deficiency Anemia

• Sources: dairy, eggs, red meat.
• Etiologic Categories
  • Pernicious (autoimmune)
  • Malabsorption (post-gastrectomy, Crohn’s, bariatric surgery)
  • Nutritional lack (strict vegans).
• Clinical Picture: fatigue, SOB, headaches, pallor, dizziness ± neuro paresthesias (noted elsewhere).
• Key Labs: B12 < 200\ \text{pg/mL} confirms deficiency; check folate concurrently.
• Treatment: IM B12 injections—preferred when gut absorption impaired; oral forms ineffective in severe deficiency.

Sickle Cell Anemia

• Genetic: autosomal recessive—both parents carry trait.
• Sickled RBCs → vaso-occlusion, ischemic pain, end-organ damage.
• RBC lifespan shrinks to 10\text{–}20\ \text{days} ➜ chronic hemolytic anemia.
• Complications: crisis pain, hypoxia, retinal ischemia/blindness, need for repeated transfusions.
• Onset: manifestations by \approx 6\ \text{months} of age (swelling hands/feet, anemia, pain crises).
• Ethical note: honor transfusion refusal (e.g., Jehovah’s Witness) ➜ document & respect autonomy.

Blood Transfusion Principles & Reactions

• Acute Hemolytic (Immediate)
  • ABO/Rh incompatibility.
  • Chills, fever, lumbar pain, tachycardia, chest tightness, DIC risk.
  • Management: STOP, disconnect, flush 0.9\% NS, vitals, send bag/labs.
• Febrile Non-Hemolytic (≤2 h)
  • Anti-WBC antibodies; common in multi-transfused pts.
  • Chills, fever, flushing, hypotension, tachycardia.
  • Prevention: leukocyte filter tubing.
• Allergic (≤24 h)
  • Urticaria, itching, flushing → may progress anaphylaxis.
  • Stop, flush NS, give IV diphenhydramine; may restart slowly if mild.
• Bacterial (Sepsis)
  • Contaminated product; wheeze, dyspnea, cyanosis, hypotension.
  • Stop, NS, send culture/pathology, broad-spectrum abx as ordered.
• Circulatory Overload (TACO)
  • Infusion rate too fast; CHF pts high-risk.
  • Crackles, edema, tachycardia; give O2, sit upright, diuretics (e.g., Lasix between units), morphine PRN.

ABO Compatibility Snapshot

• A ➜ receives A or O.
• B ➜ receives B or O.
• AB ➜ receives A, B, AB, or O (universal recipient).
• O ➜ receives only O (universal donor).

Oncology Foundations

• Cancer = Uncontrolled Cellular Growth
  • Causes: genetic mutation, faulty cell division, environmental carcinogens, oncogenic viruses.
  • Tumors named by organ + cell type (e.g., "lung adenocarcinoma").
• Progression Model: Hyperplasia → Dysplasia → Carcinoma *in situ* → Invasive malignancy.
• Malignant hallmarks: rapid replication, no apoptosis, capability to induce angiogenesis (own blood supply).
• Risk Factors: smoking, ETOH, obesity, sedentary lifestyle, poor diet, viral infections (HPV, HBV, EBV).
• Most Prevalent Cancers
  • Female: breast, lung, colorectal, uterine, melanoma.
  • Male: prostate, lung, colorectal, bladder, melanoma.
• Common Presentations: unexplained weight loss, fatigue, palpable mass, swelling, persistent pain, skin changes.

Diagnostic & Staging Tools

• Imaging: mammogram, CT, MRI depending on suspected site.
• PET scan: radioactive glucose uptake highlights hyper-metabolic (cancer) cells.
• Angiography: maps tumor blood supply for surgical/embolization planning.
• Biopsy: only definitive diagnostic method.
• Tumor Markers (supportive, not standalone)
  • BRCA 1/2 (hereditary breast/ovarian risk)
  • PSA (prostate)
  • CA-125, CEA (GI/ovarian, etc.).
• TNM Staging
  • T = Tumor size
  • N = Node involvement
  • M = Metastasis presence
  • Clinical stages 0\text{–}4:
    • 0 = in situ (confined)
    • I–II = localized
    • III = regional spread
    • IV = distant mets; "Unknown" when origin unclear.

Breast Cancer Focus

• Types
  • Ductal carcinoma (most common) – begins in milk ducts.
  • Lobular / invasive forms spread to surrounding tissue.
  • May be Estrogen- or Progesterone-Receptor (ER/PR) positive—hormone-driven growth.
• Risk Factors: BRCA mutations, > age 50, family history, ETOH/smoking, chest radiation, prolonged estrogen exposure (HRT).
• Clinical Signs: palpable lump, breast swelling, nipple discharge/retraction, "peau d’orange" skin, axillary node enlargement.
• Screening
  • Mammogram annually starting 40\text{–}45 yrs per updated guidelines.
  • Diagnostic mammogram if symptomatic/palpable mass.
  • Clinical breast exam at yearly GYN visit.
• Diagnostics: targeted MRI, core-needle biopsy (definitive), hormone-receptor & HER-2 testing, tumor grading.

Ethical & Practical Considerations

• Always respect patient autonomy (e.g., blood refusal). Document informed refusal & provide alternative strategies when possible.
• Weigh benefits/risks of hormone replacement in estrogen-sensitive malignancy history.