Lecture 1: Components of Blood

Question 1

What are the three components of blood?

Answer 1

(1) Plasma
- Water
- Proteins
- Non-protein solutes
(2) Leukocytes and Platelets
(3) Packed Red Blood Cells

Question 2

What is plasma comprised of?

Answer 2

• Water
• Proteins (Albumin, Globulins, Coagulation factors)\
• Solutes (Na+, Cl-, Ca++, HCO3-, urea)

Question 3

How much of extracellular fluid does plasma represent?

Answer 3

1/3

Question 4

What does the plasma act as?

Answer 4

Transportation system both to and from the body tissues

Question 5

T/F All blood (Red and White) cells come from pluripotent stem cells in bone marrow?

Answer 5

TRUE

Question 6

What is another term for Red Blood Cell?

Answer 6

Erythrocyte

Question 7

Where is the bone marrow located?

Answer 7

Axial skeleton in adults (long bones)

Question 8

What are RBCs regulated by? How are they regulated?

Answer 8

Erythropoietin (hormone); it is released by renal tubules in response to hypoxia or decreased RBC

Question 9

RBCs are dependent on what substances?

Answer 9

• Iron
• B12
• Folic acid
• B6
• Thyroid hormone

Question 10

What is the earliest identifiable form of RBC? How many mature RBCs does it produce?

Answer 10

Proerythroblast; 8

Question 11

T/F Nucleated RBCs are present in circulation.

Answer 11

FALSE; erythroblasts lose their nucleus right before entering circulation

Question 12

What is a good indicator of bone marrow production?

Answer 12

Reticulocytes

Question 13

How can you distinguish a reticulocyte from a mature RBC (as both are in circulation)?

Answer 13

Reticulocytes are larger and contain ribosomes

Question 14

Around how many reticulocytes should be in circulation?

Answer 14

Number of reticulocytes circulating should be equal to the number of RBC being removed from circulation

Question 15

Life span of RBC

Answer 15

120 days

Question 16

What happens to degraded RBCs?

Answer 16

They are partially recycled and partially converted into bilirubin

Question 17

What do erythrocytes do?

Answer 17

• Transport O2 from the lungs to the tissues of the body (HgB is the binding protein)
• Transport CO2 from the tissues to the lungs

Question 18

Why are RBCs shape important?

Answer 18

Bi-concave shaped cells to be flexible and fit through capillary system

Question 19

What are the 3 types of Granulocytes? What are their function?

Answer 19

(1) Neutrophils- phagocytic cells that respond to foreign bodies and bacteria
(2) Eosinophils- attack protozoa and helminths
(3) Basophils- become mast cells (hypersensitivity reactions)

Question 20

What type of Granulocyte accounts for most of the WBC in circulation?

Answer 20

Neutrophils (60-70%)

Question 21

What do monocytes play a role in?

Answer 21

• Become tissue macrophages

- Play a role in inflammation and initiating an immune response

Question 22

What 2 types of lymphocytes are there? What are their differences?

Answer 22

• B: differentiation occurs in bone marrow; synthesize antibodies; provide humoral immunity
• T: differentiation occurs in thymus; destroy foreign cells or infected native cells; provide cell mediated immunity

Question 23

Where are lymphocytes found?

Answer 23

In the lymphatic organs where they function as part of the immune system

Question 24

What is another name for platelets?

Answer 24

Thrombocytes

Question 25

What do platelets play a role in?

Answer 25

- Hemostasis - Inflammation - Wound healing

Question 26

What is the life span of a platelet? Where are they derived?

Answer 26

8-10 days; megakaryocyte in bone marrow

Question 27

What is the primary role of Hemoglobin? What is the iron containing portion of HgB?

Answer 27

Transports O2; Heme

Question 28

T/F Iron is stored well within the body.

Answer 28

False; daily dietary iron is necessary

Question 29

What are the 2 types of iron and where are they located?

Answer 29

- Active metabolic iron (80%; found within RBC) | - Iron reserve (ferritin- stored outside of the cell; stored in liver, spleen, bone marrow-hemosiderin)

Question 30

Hgb (meaning and values)

Answer 30

- the amount of Hgb in 100mL of blood - provides an indication of the O2 transport of the blood - Females: 12.3-15.3 g/dL - Males: 14-17.5 g/dL

Question 31

Hct (meaning and values)

Answer 31

- packed cell volume, percentage volume of blood that is made up of erythrocytes - usually 3 times the value of Hgb (decrease in anemia) NORMAL - Females: 36-45% - Males: 42-50%

Question 32

MCV (meaning and values)

Answer 32

- Mean Corpuscle Volume - Average size of a RBC - calculated by dividing Hct by RBC count - Normal: 80-100 fL

Question 33

WBC (meaning and values)

Answer 33

- number of leukocytes in a cubic millimeter of blood - increased in infections; decreased often but may represent malignancy - Normal: 4.4-11.3 x 10^3 cells/mm3

Question 34

Platelet count (meaning and values)

Answer 34

- Number of platelets in a cubic millimeter of blood - Normal: 150,000-450,000 (will read "150" on CBC)

Question 35

T/F ESR is not included in routine CBC.

Answer 35

TRUE (Erythrocyte Sedimentation Rate)

Question 36

What is ESR and what do increased and decreased ESR indicate?

Answer 36

- The rate at which erythrocytes settle from the blood - Increase: inflammation, infection, pregnancy - Decrease: CHF, sickle cell anemia

Question 37

What is a Wright stained blood smear?

Answer 37

- allows for manual evaluation of blood | - Looks at WBC and RBC morphology

Question 38

WBC morphology (blood smear)

Answer 38

Determines the type of leukocytes in circulation - Neutrophils (PMN: 45-73%, Band: 3-5%) - Eosinophils 0-4% - Basophils 0-1% - Monocytes 2-8% - Lymphocytes 20-40%

Question 39

Left shift

Answer 39

shift to a bunch of young, banded neutrophils; INFECTION

Question 40

RBC morphology (blood smear)

Answer 40

Determines size, shape, estimates of Hgb concentration (color of cell) and abnormalities - Normal: 7-8 micrometer in diameter - Important in determining pathology (target cells, sickle cells, spherocytes)

Question 41

Anisocytosis

Answer 41

variation in RBC size

Question 42

Poikilocytosis

Answer 42

variation in RBC shape

Question 43

T/F Reticulocyte counts come on regular CBC.

Answer 43

FALSE

Question 44

Reticulocyte count (measure and value)

Answer 44

Good indicator of RBC production - Normal: 0.5-2.5% (count should be equal to number of RBC being removed from circulation) - Elevated= anemia due to blood loss and/or hemolysis - Reduced= anemia due to problems with RBC production (vitamin def, bone marrow supp)

Question 45

What is the RPI

Answer 45

Raw Reticulocyte Count (%) x Patient's Hematocrit / 45 x 0.5

Question 46

Anemia + RPI .2

Answer 46

suggestshemolysis or acute hemorrhage

Question 47

Anemia + RPI < 1

Answer 47

consistent with decreased RBC production

Question 48

Indications for RBC transfusion

Answer 48

- Symptomatic deficit in oxygen carrying capacity - Acute blood loss: whole blood - Chronic anemia: packed RBC

Question 49

T/F Patient should be crossmatched and typed for RBC transfusion.

Answer 49

TRUE

Question 50

What is crossmatching?

Answer 50

Patient's blood is mixed with donor blood to evaluate for lysis and clotting reactions (in lab) - takes around 30 minutes

Question 51

When would you use uncrossmatched blood?

Answer 51

- in massive blood loss - with cardiovascular collapse - Group O, Rh (-)

Question 52

What is a Transfusion Reaction?

Answer 52

- antibody-mediated acute hemolytic reaction - potentially life threatening - most serious from mismatching of donor blood with recipient blood

Question 53

What is Post Transfusion Fever without hemolysis?

Answer 53

- due to presence of foreign proteins in donor plasma | - can cause urticaria

Question 54

What are platelet transfusions used for?

Answer 54

- usual dose: one unit per 10 kg body weight | - controlling bleeding in patients with thrombocytopenia due to bone marrow failure or chemo induced

Question 55

T/F Platelet transfusion is useful for secondary thrombocytopenia.

Answer 55

FALSE