PC 705 Module 6 Exam - Hematologic and Neoplasms

PC 705 Module 6 Exam - Hematologic and Neoplasms Pediatric hematologic system: -RBC count above adult levels at birth & gradually decline thereafter -Fetal Hemoglobin have an increased affinity for oxygen -Hemoglobin reaches adult levels between 6-12 months -Decreased erythrocyte lifespan for infants (60-80 days for full term; 20-30 days for premature infants) -Erythrocyte lifespan in children & adolescents is the same as adults (120 days) -Platelets are adult levels -Coagulation factors reach adult levels by 6 months -Leukocytes high at birth but gradually decline -Lymphocytes specifically might increase during 1st year of life before gradually declining Why might lymphocytes increase during a child's first year of life? -frequent viral infections -vaccinations Aging of the hematologic system: -changes little -Erythrocytes replenished slower -Iron deficiency is common -decreased lymphocyte & t-cell function -decreased humoral responsiveness -increase in clotting factors & activation -Increased adhesiveness of platelets What about chronic diseases puts an individual at risk for anemia? -suppressed erythropoiesis (decreased erythropoietin released from kidneys) -inflammation (iron sequestration from macrophages) -impaired iron utilization -failure to respond to low erythrocytes Ex: CHF Anemias can result from what 3 things? -blood loss (acute or chronic) -impaired erythrocyte production -Increased erythrocyte destruction OR a combination of these "Cytic" refers to what? cell size -microcytic means small cell size -macrocytic means large cell size "Chromic" refers to what? Hemoglobin content within the cell -hyper chromic means there is more hemoglobin which means it will look more "red" -hypo chromic means there is little hemoglobin which means it will look more "pale" What is relative polycythemia? -RBC count "appears" elevated but it's only because the plasma volume has decreased making it more "concentrated" -this happens with dehydration -this can also happen in relation to stress What could cause the RBC count to appear less than it really is? -fluid overload--causing a "dilution" of RBCs What is the main manifestation of anemia? -reduced oxygen carrying capacity causing hypoxemia and tissue hypoxia -"fatigue" is huge Symptoms of anemia depend on what? -compensation ability of the cardiac, respiratory, and hematologic system Having a lower than normal RBC content in the blood can do what? -decreases viscosity -allows blood to flow faster -causes a "hyper-dynamic state" -damaging to blood vessels -can lead to high output heart failure Is the anemia usually acute or chronic if an individual is only symptomatic on exertion? Chronic Clinical manifestations of generalized anemia? -pale skin, mucous membranes, lips, nail beds, conjunctivae due to decreased hgb -jaundice if hemolysis is occurring (build up of unconjugated bilirubin from broken down RBCs) -Tissue hypoxia--impaired healing, decreased elasticity -may have neurological symptoms depending on the cause of anemia -may have GI symptoms (abdominal pain, N/V, anorexia) -may have low grade fever from ischemic tissue If anemia is SEVERE or ACUTE what does the body do to compensate? -increased erythropoiesis (increase in reticulocytes--immature RBCs) -blood vessel constriction, SNS & RAAS system activation -fluid retention -can lead to failure of organs if the underlying cause is not corrected What are the two types of post hemorrhagic anemias? Acute blood loss or chronic blood loss What type of anemia is associated with acute blood loss? -Post hemorrhagic anemia -"normocytic-normochromic" anemia -the overall structure and content of the RBCs are normal--they are just decreased Major cause of acute blood loss anemia? Trauma Pathophysiology & clinical manifestations of acute blood loss anemia? -decreased venous return -SNS activation due to decreased BP & CO -fluids move from interstitial to vascular -tissue hypoxia causes stimulation of erythropoietin S&S related to decreased blood volume, SNS stimulation, and tissue hypoxia B12 & Folate are nutrients necessary for? -cell nuclear maturation & DNA synthesis What does the body need in order to absorb B12? -intrinsic factor--which is secreted by the parietal cells of the stomach -if intrinsic factor is released during digestion B12 can be absorbed by the small intestine -if intrinsic factor is absent--malabsorption of B12 Another word for Macrocytic cells? Meglablastic What causes a RBC to develop abnormally large (macrocytic)? -B12 or Folate deficiency -causes the cell cytoplasm to grow at a faster pace than the nuclei -however, the cell will not divide until the nucleus is mature -this results in the nucleus being much smaller compared to the cell cytoplasm--creating a "larger" cell -nuclear-cytoplasmic asynchrony -these cells can die prematurely causing decreased cells in circulation