Hematology and Blood-Physio

• Erythropoiesis is the production of red blood cells in response to low oxygen levels, starting with the release of erythropoietin from the kidneys, stimulating the bone marrow to produce more red blood cells

  
• Erythropoietin (EPO) is a hormone that stimulates the formation of red blood cells, released by the kidneys in response to hypoxia
• Factors influencing the balance between red blood cell production and destruction include hormonal controls, decreased RBC numbers due to hemorrhage, insufficient hemoglobin per RBC (iron deficiency), reduced oxygen availability, and dietary requirements like Vitamin B12 and Folic Acid
• Leukocytes (white blood cells) make up less than 1% of total blood volume and function in defense against disease, with different types having different functions
• Platelets (Thrombocytes) contain chemicals involved in clotting, form temporary platelet plugs to seal breaks in blood vessels, and work with fibrin protein to reinforce clots for healing
• Hemostasis is a fast series of reactions to stop bleeding, involving clotting factors, Vitamin K, vascular spasm, platelet plug formation, and coagulation (blood clotting)
• Coagulopathies are disorders of hemostasis, including thromboembolic disorders like Deep Vein Thrombosis (DVT) and bleeding disorders like Thrombocytopenia
• Blood transfusions are used to minimize the effects of blood loss, with packed red blood cells and fresh frozen plasma being common components
• The lymphatic system returns leaked fluids from tissues back into the blood, helps fight infection, and drains fluid from tissues and organs
• Lymph nodes cleanse lymph and activate the immune system, encountering antigens and activating lymphocytes to mount immune responses
• Fluid and Electrolytes


  Regulation of Fluids, Electrolyte Balance, Sodium, Potassium, Calcium, Magnesium, Osmolality, IV Fluid Types
• Movement of fluid through capillary wall

  • Depends on: Osmotic Pressure, Oncotic Pressure, Hydrostatic Pressure
• Osmotic Pressure


  Pressure that attracts water based on solute concentrations. Water moves from low solute to high solute areas.
• Oncotic Pressure


  Osmotic pressure exerted by proteins. Major protein is Albumin.
• Hydrostatic Pressure


  Force within a fluid compartment
• Sodium (Na)


  Major electrolyte in the extracellular fluid (90% of ECF). Essential to maintain osmolality. Regulated by kidneys and aldosterone.
• Hyponatremia


  Symptoms: altered neurologic functioning (confusion, lethargy, convulsions, agitation, difficulty concentrating). Effects: decreases osmotic pressure, hypovolemia, hypotension. Treatment: hypertonic IV solution, increase sodium intake.
• Hypernatremia


  Symptoms: dehydration, altered neurologic functioning (confusion, lethargy, convulsions, agitation, difficulty concentrating). Effects: hypertension, edema, renal failure, dry mucous membranes. Treatment: low salt diet, hypotonic IV solution.
• Potassium (K)


  Major electrolyte in the intracellular fluid. Essential for proper nerve impulse conduction, muscle contraction, and heart contraction.
• Hypokalemia


  Symptoms: Cardiac changes (arrhythmias), cardiac arrest, muscle weakness, muscle cramps. Effects: metabolic alkalosis. Treatment: potassium diet, IV Potassium Chloride.
• Hyperkalemia


  Symptoms: cardiac changes, muscle weakness, muscle cramps, paralysis. Effects: metabolic acidosis. Treatment: IV insulin (promotes K+ uptake by muscle and liver cells), low K diet.
• EKG Changes in Hypokalemia

  • U wave is formed, T wave is inverted, ST segment is depressed.
• EKG Changes in Hyperkalemia

  • T wave is peaked, QRS complex is widened, P wave is flattened.
• Calcium (Ca)


  Normally stored in bones. Parathyroid hormone (PTH) increases calcium levels. Requires Vitamin D for cellular absorption of Ca.
• Hypocalcemia


  Symptoms: neuromuscular excitability (convulsions), tetany (rigidity), spasms, numbness in extremities. Effects: metabolic alkalosis. Treatment: diet high in calcium and Vitamin D. Clinical Tests: Chvostek's Sign, Trousseau's Sign.
• Hypercalcemia


  Symptoms: cardiovascular changes (dysrhythmias). Causes: hyperparathyroidism. Treatment: diet, calcitonin (inhibits calcium reabsorption).
• EKG Changes in Hypocalcemia

  • QT interval is lengthened.
• EKG Changes in Hypercalcemia

  • QT interval is shortened.
• Magnesium (Mg)


  Heavily influenced by diet. Alcoholism is a great risk factor for hypomagnesemia.
• Hypomagnesemia


  Symptoms: neuromuscular excitability (convulsions), muscle weakness. Effects: changes in mood and level of consciousness. Treatment: diet, avoid alcohol use.
• Hypermagnesemia


  Symptoms: loss of deep tendon reflexes, depressed respirations. Effects: renal failure. Treatment: diet.
• EKG Changes in Hypomagnesemia

  • T wave is peaked, ST segment is depressed.
• EKG Changes in Hypermagnesemia

  • QRS complex is widened.
• Isotonic Solutions


  Concentration of fluid is similar to that of blood plasma. Isotonic solution doesn't shift solutes, but distributes them equally.
• Isotonic Solutions


  • 0.9% NaCl (Normal Saline), Lactated Ringers (LR)
• Hypotonic Solutions


  Concentration of solutes in fluid is LESS than that of blood plasma. Water moves into cell as there are more solutes in the cell.
• Hypotonic Solutions


  • 0.45% NaCl (1/2 NS), 5% Dextrose in Water (D5W)
• Hypertonic Solutions


  Concentration of solutes in fluid is MORE than that of blood plasma. Water moves out of the cell as there are more solutes in the solution.
• Hypertonic Solutions


  • Higher NaCl concentrations (above salinity of NS, 0.9%), 3% NaCl, 5% NaCl, 5% Dextrose in Normal Saline (D5NS), 5% Dextrose in Lactated Ringers (D5LR), 10% Dextrose in Water (D10W), Total Parenteral Nutrition (TPN)
• Colloid Solutions


  Act as blood volume expanders or plasma expanders. Are large protein molecules that don't pass through semipermeable membranes, so they remain in the intravascular compartment.