Formulas and reference ranges

Reference range in males for RBC count:

4.5*10¹²- 5.5×10¹²

Reference range in females for RBC count:

4.0×10¹²- 5.0×10¹²

Hemoglobin abbreviation(s):

Hgb or Hb

Reference range in males for Hgb:

14-18 g/dL

Reference range in females for Hgb:

12-16 g/dL

Abbreviation for hematocrit:

Hct

Reference range in males for Hct:

42-52%

Reference range in females for Hct:

36-46%

What are the RBC indices?

MCV
MCH
MCHC

MCV stands for:

Mean Corpuscular Volume

Reference range for MCV:

80-100 fL

MCV formula:

(Hct*10)/RBC count

MCH stands for?
What does it measure?

Mean corpuscular hemoglobin
Average weight of hemoglobin

Reference range for MCH:

28-34 pg

MCHC stand for?
What does it measure?

Mean corpuscular hemoglobin concentration

RDW stands for?
What does it measure?

Red cell distribution width
Variation on cell size (Anisocytosis)

Reference range for RDW:

11.5-14.5%

T/F: Under normal conditions, the quantity of retics in the bone marrow is equal to the number of retics in peripheral blood.

True

What’s the purpose of taking a relative reticulocyte count?

Monitoring erythropoiesis
Detection of RBCs still containing RNA

What is the formula for relative retic count?

(( # of retics) * 100)/1000

When would you use a corrected retic count (CRC)?

When dealing with a patient with anemia

Formula for CRC:

(Retic%*Hct)/45

What does RPI measure?

Erythropoietic activity when stress retics are present (anemia)

What is the formula for RPI:

(CRC)/correction factor

What is the preferred method for counting retics?

Absolute retic count (ARC)

What is the ARC formula:

(retic% * RBC count)/100

Reference range for ARC:

25-75×10⁹

What are the formulas for rule of 3?

RBC*3=Hgb
Hgb*3=Hct±3

Why would we take a corrected WBC count?

If there’s a presence of nucleated RBCs

What is the formula for corrected WBC count?

(WBC count*100)/(100+# of NRBCs)

What is the reference range for corrected WBC count?

4.5-11.5×10⁹/L