Hematology Quiz on Blood Functions

Hematology Overview

• Hematology is the study of blood, blood cells, lymph, and organs involved in blood formation and storage
• Blood consists of plasma and cells.
• Key functions of the hematologic system include circulating oxygen, nutrients, hormones, and metabolic wastes; protecting against pathogens; and maintaining coagulation, fluid and acid-base balance, body temperature

Hematopoiesis

• Hematopoiesis is the process of blood cell formation in bone marrow
• Pluripotent stem cells in the bone marrow are crucial for this process
• Red blood cells (RBCs) carry oxygen; low RBCs lead to hypoxia
• White blood cells (WBCs) fight infections; low WBCs lead to infections
• Platelets aggregate to form clots; low platelets lead to bleeding

Accessory Organs of Blood Formation

• Spleen: Stores WBCs, RBCs, and platelets; filters blood and destroys old cells; removal increases infection risk
• Liver: Produces clotting factors (prothrombin); stores blood and iron; liver problems can cause clotting/bleeding issues

Jaundice Assessment

• Sclera, palate, palms, and skin can turn yellow in cases of jaundice.
• Follow up checking for hyperbilirubinemia by checking the following body areas.

Stages of Hemostasis

• Vessel injury: Causes spasms, restricting blood flow
• Vascular spasm: Vessel constricts to reduce blood loss
• Platelet plug formation: Platelets aggregate and form a plug to stop bleeding
• Coagulation: Complex cascade of clotting factors leading to fibrin mesh clot formation.
• Clot retraction/growth factors: Edges of wound contract, attracting new cells to repair the injury
• Clot dissolution(fibrinolysis): The breakdown of the clot as healing progresses.

Anti-clotting forces

• Plasminogen activators activate plasmin, an enzyme that breaks down fibrin clots.
• This process is crucial for preventing blood clots from becoming too large or staying in place.
• The clot eventually breaks down into fibrin degradation products, completing the process of fibrinolysis.

Hematological Assessment

• History: OPQRSTU (Present Illness); past medical history; family history; nutrition.
• Physical Exam: Skin, HEENT, Respiratory, Cardiovascular, GU, MS, GI, and Neuro.

Hematological Lab Values

• RBC (4.2-5.14)
• Hemoglobin (Hgb) (12-18)
• Hematocrit (Hct) (38-49)
• WBC (5-10)
• Platelets (PLT) (150-450)
• PT (10-13 seconds)
• INR (0.8-1.1) - normal; (2.0-3.5) - if on warfarin (coumadin)
• PTT (21-35 seconds) - normal for Heparin therapy

Other Diagnostic Tests

• Bone marrow aspiration: Posterior superior iliac crest is most commonly used site.
• Local anesthetic is used
• Apply pressure for 5-10 minutes to help stop bleeding
• Monitor for bleeding, treat pain
• Educate patient about signs/symptoms of infection after procedure

Age-Related Changes

• Bone mass and intracellular fluids decrease with age
• Decreased blood volume and liver function
• Decreased albumin
• Decreased hematopoiesis and iron binding
• Anemia
• Increased risk of infection
• Increased risk of bleeding

Care of Patients with Hematologic Problems

• Prevent hypoxia, infection, and bleeding

Anemia

• Insufficient oxygen transport leads to cellular hypoxia
• Various causes, including poor diet, malabsorption, genetic disorders, and bone marrow disease
• Classifications (microcytic, macrocytic, etc) based on RBC size are used for diagnosis

Anemia Treatment

• Erythropoietin: stimulates bone marrow RBC production
• Iron: crucial for Hb formation; deficiencies lead to anemia
• Vitamin B12: critical for proper RBC production
• Folic Acid: needed for DNA synthesis for cell division
• Addressing underlying causes and implementing supportive measures are essential for treatment.

Anemia Medication Concerns

• Folic acid can mask signs of pernicious anemia, requiring proper diagnosis before treatment
• Iron administration dosage in children should be monitored carefully due to potential overdose concerns.

Hematopoietic Growth Factors

• Erythropoietic drugs (stimulate RBC production)
• Colony-stimulating factors (increase WBC and platelet production)
• Platelet-promoting drugs (promote platelet production)

Common Adverse Effects of Hematopoietic Drugs

• Cardiovascular effects (edema).
• Gastrointestinal issues (anorexia, nausea, vomiting).
• Integumentary effects (rash, alopecia, skin infections). Respiratory effects
• Others (fever, bone pain)

Contraindications for Hematopoietic Drugs

• Known allergies
• Elevated Hgb (Epogen)
• Infection (Filgrastim)

Interactions of Hematopoietic Drugs

• Colony-stimulating factors and myelosuppressive drugs may cancel each other out if administered within 24 hours.

Polycythemia

• Too many RBCs leads to increased blood viscosity,
• Problems with oxygen transport and blood flow.
• Treatment usually involves therapeutic phlebotomy or apheresis to reduce the blood cell count.

Leukemia

• Cancer of the WBCs, characterized by an overabundance of immature, ineffective WBCs.
• Frequent infections, anemia, and bleeding problems are common.

Leukemia Treatment

• Chemotherapy
• Radiation
• Bone marrow transplant

Care of Immunosuppressed Patients

• Avoid raw fruits, veggies, standing water (longer than 15 minutes), crowds/sick individuals, fresh plants/flowers and avoid rectal temps/suppositories

Myelodysplastic Syndromes

• Group of disorders characterized by the ineffective production of blood cells.
• Pancytopenia (low levels of all blood cells).
• Chronic hypoxia, frequent infections, and bleeding are common symptoms.

Care of Patients with Thrombocytopenia

• Avoid injury; use soft bristle toothbrush, electric razors, stool softeners, and maintain a clutter-free environment
• Avoid rectal temps, intercourse, blowing nose
• Avoiding injections and non-essential blood draws is crucial to avoid further bleeding risk.

Thrombocyte Disorders (Clotting Problems): ITP & TTP

• ITP: Autoimmune disorder with increased destruction of platelets by the spleen
• TTP: Disruption of the clotting process due to abnormal platelet clumping
• Treatment for ITP may include immunesuppressants while TTP requires addressing the underlying cause.

Clotting Factor Disorders: Hemophilia and HIT

• Hemophilia: Genetic deficiency of clotting factors, leading to prolonged bleeding from minor injuries, and other complications.
• HIT: Autoimmune response to heparin, resulting in potentially serious blood clots and thrombotic complications.

Hemophilia Teaching

• Important to avoid injury, maintain good hygiene, and teach patients/caregivers how to assess for bleeding abnormalities.

Hemophilia Treatment

• Bleeding/injury management- administer missing clotting factor
• Administer antifibrinolytics to prevent clot breakdown
• Desmopressin to increase platelet aggregation
• RICE for injury management
• Acetaminophen as needed; avoiding NSAIDs because further impairing platelet aggregation. Avoid NSAIDs.

Lymphomas

• Hodgkin and Non-Hodgkin's are cancers of lymphocytes leading to swollen lymph nodes
• Multiple symptoms include weight loss, night sweats, persistent fever, and cough
• Diagnosis and treatment vary greatly from the type

Multiple Myeloma

• Cancer of plasma cells (B-lymphocytes)
• Characterized by overabundant abnormal plasma cells, bone marrow crowding, and the formation of cancer tumors in the bone.
• Can cause pathological fractures.
• Associated with hypercalcemia (high blood calcium levels)
• Diagnosis and treatment vary greatly from the type.