Unit 3 - CBC

Question 1

Volume of blood in the body

Answer 1

4-6 Liters

Question 2

Approximately what % of the total body weight is blood?

Answer 2

8%

Question 3

What percent of blood is plasma?

Answer 3

~55%

Question 4

What makes up plasma?

Answer 4

Proteins, electrolytes, hormones
Water

Question 5

What percent of blood is cellular elements?

Answer 5

~45%

Question 6

What is the optional component in CBC?

Answer 6

Microscopic evaluation

Question 7

What does extra anticoagulant do?

Answer 7

Cause shrinkage

Question 8

Ideal peripheral smears are made within

Answer 8

3 hours

Question 9

What does EDTA do

Answer 9

Chelates calcium

Question 10

Perform CBC on room temp blood within

Answer 10

6 hours

Question 11

Perform CBC on refrigerated blood within

Answer 11

24 hours

Question 12

When should a sample be prepared for blood smear?

Answer 12

within 2-3 hours of collection

Question 13

What if a blood smear is prepared after more than 5 hours after collection have passed

Answer 13

Results in artifacts

Question 14

When is it acceptable to prepare a blood smear without anticoagulant?

Answer 14

Smear from direct finger puncture

Question 15

When must a finger puncture blood smear be prepared?

Answer 15

Immediately

Question 16

When to reject CBC specimen?

Answer 16

Too old
Any clotting! even if microscopic

Question 17

Why is clotting not accepted for CBC specimen?

Answer 17

Activates and consumes coagulation factors
Blood cells bind

Question 18

WBC reference range in CBC

Answer 18

4.0-11.0x10^3 cells/mcL
No sex difference

Question 19

RBC reference range in CBC

Answer 19

Male: 4.50-5.90x10^6 cells/mcL
Female: 3.80-5.20x10^6

Question 20

PLT reference range in CBC

Answer 20

150-450x10^3
No sex difference

Question 21

Hgb concentration reference ranges

Answer 21

Male: 13.5-17.5 g/dL
Female: 12.0-16.0 g/dL

Question 22

Hct reference ranges

Answer 22

Male: 42-52%
Female: 36-46%

Question 23

Which of the indices are not averages?

Answer 23

RDW: Red cell distribution width

Question 24

What is MCV

Answer 24

Mean corpuscular volume

Question 25

MCV reference ranges

Answer 25

80.0-100.0fL

Question 26

Normocytic

Answer 26

80-100fL

Question 27

Microcytic

Answer 27

<80fL

Question 28

Macrocytic

Answer 28

>100fL

Question 29

What is MCH

Answer 29

Mean corpuscular hemoglobin

Question 30

MCH Reference interval

Answer 30

26.0-36.0 pg

Question 31

Normochromic

Answer 31

26.0-36.0 pg

Question 32

Hypochromic

Answer 32

<26.0 pg

Question 33

Hyperchromic

Answer 33

>36.0 pg

Question 34

What is MCHC

Answer 34

Mean corpuscular hemoglobin concentration

Question 35

MCHC reference interval

Answer 35

32.0-36.0 g/dL

Question 36

Which index would you rather use for cell color?

Answer 36

MCHC

Question 37

What does MCH not take into account?

Answer 37

Cell size

Question 38

Larger cells have... ___ hgb?

Answer 38

More

Question 39

Normochromic (MCHC)

Answer 39

32-36 g/dL

Question 40

Hyperchromic (MCHC)

Answer 40

>36 g/dL

Question 41

Hypochromic (MCHC)

Answer 41

<32 g/dL

Question 42

Hyperchromic is never valid except in...

Answer 42

Spherocytes

Question 43

What is RDW?

Answer 43

Variation of size in RBC population

Question 44

MCV Calculation

Answer 44

(HCT/RBC)*10 = fL

Question 45

MCV is evaluating...

Answer 45

Size of cells

Question 46

MCH is evaluating...

Answer 46

Concentration of hgb in cell. Evaluating color only

Question 47

MCHC is evaluating...

Answer 47

Concentration of hgb in cell taking into account size

Question 48

MCH Calculation

Answer 48

(Hgb/RBC)*10 = pg

Question 49

MCHC Calculation

Answer 49

(Hgb/HCT)*100 = g/dL

Question 50

RDW calculation

Answer 50

(1SD of MCV/MCV)*100 = %

Question 51

High RDW & What it means

Answer 51

>14.5% indicates the RBC is heterogenous

Question 52

Anisocytosis

Answer 52

Variation in red cell size

Question 53

When does high RDW occur?

Answer 53

Diseases with abnormal RBC Transfusions Microcytosis (MCV) because denominator is lower

Question 54

When does Low RDW occur?

Answer 54

No known disease causes this Macrocytosis can cause a lower number because denominator is higher

Question 55

What makes a good blood smear?

Answer 55

2/3 to 3/4 of slide Thumbprint shape Lateral edges visible Smear is smooth Feathered edge Entire blood drop is used

Question 56

What components of Wright Giemsa stain ?

Answer 56

Fixative - Methanol Eosin Methylene Blue

Question 57

What pH should romanowski stain be at?

Answer 57

6.4-6.8

Question 58

Can you wave or blow a blood smear to make it dry faster?

Answer 58

no

Question 59

High MCV =

Answer 59

Macrocytes

Question 60

Low MCHC =

Answer 60

Large central pallor

Question 61

High RDW =

Answer 61

Anisocytosis or variation in abc

Question 62

What is the rule of 3?

Answer 62

Internal QC check on values related to RBC, Hgb, Hct

Question 63

Rule of 3 formulas

Answer 63

RBC count x 3 = Hgb Hgb x 3 = Hct ± 3%