Calculations to Memorize

Question 1

%Transferrin saturation

Answer 1

%Saturation = (serum iron/TIBC) * 100

Question 2

UIBC

Answer 2

UIBC = TIBC - serum iron

Question 3

TIBC

Answer 3

TIBC (µg/dl) = serum transferrin (mg/dl) X 1.43 according to Harr
or TIBC = serum iron + UIBC

Question 4

Unconjugated/indirect bilirubin

Answer 4

Unconjugated bilirubin = Total bilirubin - direct bilirubin

Question 5

LDL/Friedwald equation

Answer 5

LDL-C = Total cholesterol - HDL - (triglyceride/5)

Question 6

Albumin/Globulin (A/G) ratio

Answer 6

1.1:1.8

Question 7

Glomerular filatration rate (ml/min)

Answer 7

urine creatinin/plasma creatinine X volume

Question 8

Creatinine clearance

Answer 8

creat clearance = (urine creat/plasma creat) X (volume/time (min)) X (1.73/BSA)

Question 9

Beer’s law

Answer 9

A = Ebc
E = molar absorptivity
b = length of light path
c = concentration of analyte

Question 10

Corrected WBC counts when nRBC < 10

Answer 10

Corrected WBC = (WBC X 100)/(nRBC + 100)

Question 11

Manual hemocytometer count (cells/ml)

Answer 11

• cells/ml = (avg # cells/volume counted) X df
  OR
• cells/ml = (avg #cells/ # primary squares) X 10 X df

Question 12

MCV (fL)

Answer 12

MCV = (Hct X 10/RBC in millions

Question 13

MCH (pg)

Answer 13

MCH = (Hgb X 10)/ RBC in millions

Question 14

MCHC (g/dl)

Answer 14

MCHC = (Hgb/Hct) X 100