Exam 4 (Formulas, Reference Ranges)

Question 1

WBC Count Units

Answer 1

One decimel place x 10^3/mm^3

Ex: 5,5000 is 5.5 x 10^3/mm^3

Question 2

PLT Count Units

Answer 2

Whole number, no decimels x 10^3/mm^3

Ex: 350,000 is 350 x 10^3/mm^3

Question 3

Manual WBC Formula

Answer 3

(Count Average x Dilution x 10)/# primary squares

Ex: Average 250, Dilution 1:20, 4 primary square

(250 x 20 x 10) / 4

Question 4

Manual PLT Formula

Answer 4

(Count Average x Dilution x 10)/ portion of primary squares

Ex: Average 250, Dilution 1:1000, 10/25 primary square

(250 x 100 x 10) / (10/25)

Question 5

WBC Adult Reference Range

Answer 5

4.4 - 11.0 x 10^3 WBC/mm^3

Question 6

RBC Male & Female Reference Ranges

Answer 6

Male: 4.5 - 5.9 x 10^6/mm^3

Female: 4.0 - 5.2 x 10^6/mm^3

Question 7

PLT Adult Reference Range

Answer 7

150 - 400 x 10^3/mm^3

Question 8

Primary square volume

Answer 8

0.1 mm^3

Question 9

Secondary square volume

Answer 9

0.004 mm^3

Question 10

Tertiary square volume

Answer 10

0.00025 mm^3

Question 11

RBC Count Units

Answer 11

Two decimel places x 10^6/mm^3

Ex: 4,230,000 becomes 4.23 x 10^6 / mm^3

Question 12

Corrected WBC Formula

Answer 12

if more than 5 nRBCs are present

(100 x uncorrected WBC) / (100 + nRBC)

Question 13

Beer’s Law (what is it used for)

Answer 13

Used to calculate the concentration of hemoglobin in an unknown sample

Question 14

Beer’s Law Formula & Units

Answer 14

( [ ] of unknown/ [ ] of known ) / (Abs. or unknown / absorbance of known) x dilution

Where dilution = (TOTAL volume/sample volume)

Reported in grams/deciliter!!! Make sure to convert if known hemoglobin is given in mg/dl (divide by 1000).

Question 15

Hemoglobin Male & Female Reference Ranges

Answer 15

Male: 13.5 - 17.5 g/dl

Female: 12.0 - 16.0 g/dl

Question 16

Hematocrit definition

Answer 16

% of whole blood occupied by RBCs

Varies with age, sex, altitude, nutrition, smoking

Question 17

Rule of 3

Answer 17

RBC x 3 ~ HgB

HgB x 3 ~ Hct

Question 18

Hematocrit Male & Female Reference Ranges

Answer 18

Male: 41.0 -53%

Female: 36.0 - 46.0%

Question 19

Mean Cell Volume Formula

Answer 19

(Hematocrit x 10) / RBC in millions

Question 20

MCV Reference Range

Answer 20

80.0 - 96.0 fl

Question 21

Mean Cell Hemoglobin Formula

Answer 21

(Hemoglobin x 10) / RBC in millions

Question 22

Mean Cell Hemoglobin Reference Range

Answer 22

29.0 - 32.0 pg

Question 23

Mean Cell Hemoglobin Concentration

Formula

Answer 23

(Hemoglobin/Hematocrit) x 100

Question 24

MCHC Reference Range & Troubleshooting

Answer 24

33.4-35.5 g/dl or %

Should never be <30% or >36%

Question 25

Red Cell Distribution Width reference range

Answer 25

11.5 - 15.0 g/L or %

Question 26

Retic Math Process

Answer 26

Retics counted = 60 (ex, 60 found after 111 cells counted), patient 35% Hct

Raw Retic % = 6.0%

Corrected Retic = 6.0 x (35/45) = 4.7%

Days to maturation =
45-35 = 10
10/2 = 5
5 * 0.1 = 0.5
1 + 0.5 = 1.5 days

RPI = 4.7/1.5 = 3.1%

Question 27

RPI Reference Range

Answer 27

0.5 - 1.5%

1 is normal, 3 is an “appropriate response” to low hematocrit

Question 28

ESR Male & Female Reference Ranges

Answer 28

Male: 0-20 mm/hr

Female: 0-30 mm/hr

Question 29

RBC Histogram Normal distribusion

Answer 29

large peak at ~80-100, small tail to 200

Question 30

PLT Histogram Normal Distribution

Answer 30

Main peak between 2 & ~15, medium tail to 20.

Question 31

WBC Histogram Reference Ranges

Answer 31

Lymphs: 50-90 fl

Monos: 90-160 fl

PMNs: 160-450 fl

Question 32

Threshold

Answer 32

Electrically setting a size limit for the pulse size

Question 33

Channel

Answer 33

the area between thresholds (a subgroup of cells by size)