Ch. 13-Disorders of Red Blood Cells

Why do so many older people develop anemia

because of chronic disease

Why can skin and mucous membranes are pale in someone who presents with anemia

because of insufficient hemoglobin

Why don't the effects of sickle cell anemia show up until a patient is school aged

because of the different hemoglobin in babies

Why are the red blood cells of older adults are not replaced as promptly as younger people

because of the effects of stress over time

What kind of thalassimias affects only adult hemoglobin

beta thalassimias (alpha affects both fetal and adult)

In what form of thalassemia do Heinz bodies impair DNA synthesis and cause damage to the red cell membrane

beta-thalassemia

What are 3 causes of anemia

blood loss, hemolysis, and impaired RBC production

Red blood cells (erythrocytes) are made in the ________ and destroyed in the _________

bone marrow, spleen

How do you calculate the mean cell volume (MCV) of a red cell

by dividing hematocrit by red cell count

What causes anemia due to raynaud phenomenon

cold-reacting antibodies

Mature red blood cells are also known as _________

erythrocytes

What kind of blood cells is the most common

erythrocytes

What occurs when red cells become less deformable, making it difficult for them to traverse the splenic sinusoids

extravascular hemolysis

True or False: Thalassemias are inherited disorders of platelet synthesis that cause severe bruising and bleeding

false

True or false: iron deficiency anemia only affects infants and toddlers

false

What can provide an index of body iron store for a low hemoglobin count

ferritin

How many molecules of oxygen can be carried by one molecule of hemoglobin

four (each hemoglobin molecule has two alpha and two beta protein chains. Each chain contains one heme group that binds to O2)

Rh disease of the newborn is an example of __________ anemia

hemolytic

What stimulates the secretion of erythropoietin

hypoxia (erythropoiesis is governed for the most part by tissue oxygen needs)

Why would administration of albumin help a burn patient

in burn patients, protein leaks out of the vascular spaces and leads to edema. Administration of albumin will help to increase intravascular volume and blood pressure and decrease edema

What occurs as a result of transfusion reaction

intravascular hemolysis

The rate at which hemoglobin is synthesized depends on availability of which substance

iron (for heme synthesis)

What usually causes microcytic hemochromic anemia

iron defficiency

What is a major complication of beta-thalassemia

iron overload (can be reduced by iron chelation therapy)

How do erythrocytes bring oxygen to the tissues

it binds to its heme groups

What are the benefits of umbilical blood donation

it can provide stem cells for transplantation

What does fluorescent light at 420 nm to 470 nm wavelength do to the bilirubin in physiologic anemia

it converts the bilirubin into a soluble form that is easily excreted in the stool and urine

If red blood cell destruction is excessive, bilirubin production is increased, causing a yellow discoloration of the skin called _________

jaundice

What are caused by impaired DNA synthesis that results in enlarged red cells

megaloblastic anemias (the mean corpuscular volume is over 100 fL)

The function of red blood cells is to transport __________ from the lungs to the tissues

oxygen

What is a form of megaloblastic anemia (elevated MCV) caused by atropic gastritis or gastrectomy, ileal resection, inflammation or neoplasms in the terminal ileum and malabsorption syndromes that leads to failure to absorb vitamin B12

pernicious anemia

What kind of anemia results from a vitamin B12 deficiency

pernicious anemia (from things like gastrectomy)

What causes increased red cell breakdown and the inability of the immature liver to conjugate bilirubin and can develop on the 2nd or 3rd day of life

physiologic jaundice

What is unregulated overproduction of the red cell mass is termed as

polycythemia

What is a neoplastic disease of the pluripotent cells of the bone marrow characterized by an absolute increase in total red blood cell (RBC) mass accompanied by elevated white cell and platelet counts.

polycythemia vera

What is characterized by an absolute increase in total red blood cell mass

polycythemia vera (primary polycythemia)

What results in a loss of plasma volume

relative polycythemia

What results from a physiologic increase in the level of erythropoietin, commonly as a compensatory response to hypoxia (conditions causing hypoxia include living at high altitudes, chronic heart and lung disease, and smoking)

secondary polycythemia

After birth, red blood cells are normally made in what location

the bone marrow

Which organ is responsible for erythropoietin production

the kidneys

What sites are used in all people older than 12 to 18 months of age for a bone marrow biopsy

the posterior or anterior iliac crest, the sternum, and the spinous processes of T10-L4

What organ is particularly vulnerable to abnormal hemoglobin S (associated with sickle cell anemia)

the spleen

What organ is responsible for destruction of red blood cells

the spleen

Why is a biconcave shape best for the erythrocyte

the thinness of the cell membrane enables oxygen to diffuse rapidly between the exterior and innermost regions of the cell

How can polycythemia lead to a blood clot

too much red blood cells cause a thickening of the blood and an increased risk of clots

Sickle cell disease is a chronic disorder that results from changes in the shape, rather than the size, of red blood cells

true

True or false: the rate at which hemoglobin is synthesized depends on the availability of iron for heme synthesis

true

True or false: there are two major types of hemoglobin: adult hemoglobin (HbA) and fetal hemoglobin (HbF)

true

Which foods are rich in folic acid

vegetables (especially greens), fruit, cereal, and meat (however, much of the vitamin is lost in cooking)

When is a blood transfusion recommended

when hemoglobin is below 7 g/dL

What is the typical life span of mature red blood cells

120 days

If an Rh-negative mother is giving birth to an Rh-positive infant, what should the nurse be prepared to administer

Rh immune globulin

Which type of deficiency is caused by pernicious anemia

Vitamin B12

What is a commonly performed screening test that determines the number of red blood cells, white blood cells, and platelets per unit of blood

a CBC (complete blood count)

What is used to diagnose immune hemolytic anemias by detecting the presence of antibody or complement on the surface of the red cell

a Coombs test

What kind of polycythemia results in increased red cell mass

absolute polycythemia

What is the most abundant type of plasma protein

albumin

What is polycythemia

an increased RBC count and hematocrit greater than 50%

__________ anemia describes a primary condition of bone marrow stem cells that results in a reduction of all three hematopoietic cell lines: red blood cells, white blood cells, and platelets

aplastic

What is caused by bone marrow suppression and usually results in a reduction of white blood cells and platelets, as well as red blood cells

aplastic anemia

What describes a disorder that results in a reduction of all three hematopoietic cell lines - red blood cells, white blood cells and platelets

aplastic anemia (in 2/3rds or the cases, the cause is unknown and it is referred to as idiopathic aplastic anemia)