hematologic

Hematologic System Overview

  • Blood cell production (hematopoiesis) in bone marrow.
  • RBC production controlled by erythropoietin (EPO) due to hypoxia.
  • Requires key nutrients: B12, Folate, and Iron.

Anemia Types

  • Anemia: Insufficient healthy RBCs or hemoglobin.
    • Microcytic Anemia: Caused by inadequate iron.
    • Megaloblastic Anemia: Caused by B12/folate deficiency.

Hematologic Medications

Iron Supplements (Ferrous Sulfate)

  • MOA: Increases iron stores in the reticuloendothelial system.
  • Indication: Treat or prevent iron deficiency.
  • Side Effects: N/D/C, epigastric pain, tooth staining.
  • Antidote for toxicity: No specific antidote.

Vitamin B12 (Cyanocobalamin)

  • Absorption: Requires intrinsic factor from parietal cells.
  • Indication: Treatment of pernicious anemia.
  • MOA: Facilitates DNA synthesis.

Coagulation and Medications

Clotting Cascade

  • Multi-step process to form stable blood clots.
  • Merges intrinsic and extrinsic pathways.

Anticoagulants

  • Prevent or dissolve clot formation.
  • Risk of bleeding.
  • Includes Heparin, Warfarin, Dabigatran.
Heparin
  • MOA: Activates antithrombin, inactivating thrombin and factor Xa.
  • Indications: DVT, PE, AFIB.
  • Complications: Hemorrhage (antidote: Protamine Sulfate), HIT.
  • Monitoring: aPTT levels.
Warfarin (Coumadin)
  • MOA: Antagonizes vitamin K to prevent coagulation factors synthesis.
  • Indications: Prevent venous thrombosis, PE.
  • Complications: Hemorrhage (antidote: Vitamin K).
  • Monitoring: PT and INR.
  • Diet: Avoid vitamin K fluctuations.
Dabigatran (Pradaxa)
  • MOA: Binds to thrombin, preventing clot formation.
  • Indications: Stroke prevention in non-valvular AFIB, DVT/PE prevention.
  • Complications: Severe bleeding (antidote: Idarucizumab).
Aspirin (ASA)
  • MOA: Inhibits COX enzymes, reducing clotting factors.
  • Indications: MI prevention, ischemic strokes.
  • Complications: Risk of GI bleeding.
Clopidogrel (Plavix)
  • MOA: Inhibits platelet activation.
  • Indications: Atherosclerotic event prevention.
  • Complications: TTP, a rare adverse event.
Alteplase (Activase)
  • MOA: Dissolves clots by converting plasminogen to plasmin.
  • Indications: Acute MI, PE, and ischemic stroke treatment.
  • Complications: Severe bleeding (antidote: aminocaproic acid).