Hematocrit Determination (Worksheet #5 | M)

Question 1

What is hematocrit (what is its component)?

Answer 1

It is the volume of packed red blood cells (PRBCs) after the centrifugation of a blood sx

Question 2

What is the other term for Hct?

Answer 2

Packed cell volume (PCV) and erythrocyte volume fraction (EVF)

Question 3

How is Hct reported (what are the units used)?

Answer 3

1) Percent (%)
2) Cell volume percent (CV%)
3) Volume percent (vol%)

Question 4

What are the contributions (and advantages) of Hct determination?

Answer 4

It is one of the:
1) simplest
2) most accurate and 
3) valuable tests 
in hematological investigation

Question 5

What is more useful than RBC count when it comes to detecting cases of anemia?

Answer 5

Hct determination

Question 6

What are the values (or components) needed for the manual computation of RBC indices?

Answer 6

From the values of:

1) RBC count
2) Hemoglobin level
3) Hematocrit level

Question 7

What are the 2 methods of Hct determination?

Answer 7

1) Clay Adam’s Microhematocrit Method

2) Wintrobe Method (Macrohematocrit Method)

Question 8

What are the materials needed for Clay Adam’s method?

Answer 8

1) EDTA blood
2) Capillary tube (blue or red)
3) Sealing clay
4) Microhct centrifuge
5) Microhct reader
6) Disposable sterile blood lancet

Question 9

What is the process (or steps) of Clay Adam’s method?

Answer 9

1) Fill around 3/4 of the capillary tube w/ blood
2) Seal one end of the capillary tube w/ sealing clay (about 3 mm)
3) Centrifuge the blood at 10,000 rpm for 4 - 5 mins using a microhct centrifuge
4) Determine the lvl of PRBCs using a microhct reader

Question 10

What are the characteristics of red capillary tube (used in Clay Adam’s method)?

Answer 10

1) It is heparinized

2) It has a red colored ring at the top of the capillary tube

Question 11

What is the purpose of red capillary tube (in Clay Adam’s method)?

Answer 11

It is heparinized which is responsible for the anticoagulation of blood

Question 12

What are the characteristics of blue capillary tube (used in Clay Adam’s method)?

Answer 12

1) It is non-heparinized

2) It has a blue colored ring at the top of the capillary tube

Question 13

What is the purpose of blue capillary tube (in Clay Adam’s method)?

Answer 13

It is non-heparinized to not provide contribution to the anticoagulant properties of EDTA tube

Question 14

What is the depth of sealing to the capillary tube (for Clay Adam’s method)?

Answer 14

about 3 mm

Question 15

What is the rpm for centrifuging blood using a microhct centrifuge?

Answer 15

10,000 rpm

Question 16

What is the time for centrifuging blood using a microhct centrifuge?

Answer 16

4 - 5 mins

Question 17

What is used to determine the lvl of PRBCs?

Answer 17

Microhct reader

Question 18

What is utilized in Wintrobe method?

Answer 18

This method utilizes a wintrobe tube

Question 19

How many are the calibrations of a Wintrobe tube (used in Wintrobe method)?

Answer 19

2

Question 20

What are the 2 types of calibrations of Wintrobe tube?

Answer 20

1) 0 to 10
2) 10 to 0
* upwards

Question 21

What is the purpose of Wintrobe tube having 0 to 10 calibration?

Answer 21

It is used for ESR

Question 22

What is the purpose of a Wintrobe tube having a 10 to 0 calibration?

Answer 22

It is used for Hct

Question 23

What is the anticoagulant of choice for Wintrobe method?

Answer 23

Double oxalate

Question 24

What is the process (or steps) of Wintrobe method?

Answer 24

1) Fill the Wintrobe tube w/ blood using a Pasteur pipette
2) Centrifuge the tube at 3,000 rpm for 30 mins
3) Read the volume of PRBCs
4) Compute for the Hct lvl using the formula

Question 25

What should be used to fill the Wintrobe tube w/ blood (in Wintrobe method)?

Answer 25

Pasteur pipette

Question 26

What is the rpm in centrifuging the tube (in Wintrobe method)?

Answer 26

3,000 rpm

Question 27

What is the time duration for centrifugation of tube (in Wintrobe method)?

Answer 27

30 mins

Question 28

What is the formula used for computing the Hct lvl (in Wintrobe method)?

Answer 28

Hematocrit (%) = height of PRBCs / height of whole blood used X 100

Question 29

What are the normal values (in CU) of Hct for male and female?

Answer 29

1) Male: 40 - 54 % | 2) Female: 35 - 49 %

Question 30

What are the normal values (in SI) of Hct for male and female?

Answer 30

1) Male: 0.40 - 0.54 L/L | 2) Female: 0.35 - 0.49 L/L

Question 31

What is the conversion factor for computing the normal values of Hct?

Answer 31

0.01