Hematocrit

the hematocrit of venous blood which represents the hematocrit of peripheral blood and does not indicate the proportion of erythrocytes to plasma in the entire circulation.

venous hematocrit

is the ratio of total erythrocyte mass to total blood volume and is calculated by a different method.

body hematocrit

Packing of cells can be achieved at various centrifugal speeds maintained for various periods of time. A given hematocrit therefore expresses only the volume of erythrocytes packed under certain conditions of centrifugation. These are:

1. The radius of the centrifuge

2. The speed of centrifugation

3. The duration of centrifugation

If radius is 22.5 cm, spin tube at _____ rpm for _____

3,000 rpm for 30 minutes

If radius is 15 cm, spin tube at ____ rpm for ___

3,500 rpm for 30-45 minutes

used in determining erythrocyte indices, calculating blood volume and total erythrocyte mass, and establishing whether or not the patient a patient is anemic

hematorcrit

low hematorcrit indicates the cincentration of erythrocytes is ___

reduced

normal hematocrit value at birth

45% to 60%

normal hematocrit value of women

36% to 48%

normal hematocrit value of men

40% to 55%

does hematocrit incrase/decrease after 50 yrs old

decrease

does hct increa/decrease in anemia?

decrease

does hct increase/decrease in polycythemia

increase

manual method

1. macrohematocrit

2. microhematocirt

automated method (hct is a computed parameter)

hct= mcv x rbc

anticoagulant used in wintrobe and landsberg

double oxalate

anticoagulant used in von allen

sodium oxalate

anticoagulant used in haden

sodium oxalate

anticoagulant used in sanford margath

sodium oxalate

anticoagulant used in bray

heparin

length and bore of wintrobe tube

11.5 cm; 3mm

wintrobe tube should be calibrated from ___ to ___ for ESR

0 to 100mm

wintrobe tube should be calibrated from ___ to ___ for hct

100 to 0mm

speed centrifugation of wintrobe tube

2,000 to 2,300 x g for 30 minutes

name the macromethods

1. wintrobe and landsberg

2. van allen

3. haden

4. sanford margath

5. bray

antocoagulant used for Adam (micromethod)

heparin

advantages of Adam:

1. less blood

2. less time consumed

3. better packing of cells

length and bore of micromethod- adam

7 to 7.5 or 70 to 75mm

micromethod- Adam holds about ____ of whole blood or filled at least ____

0.5ml; 5cm

clay seal for micromethod - adam should be around

4 to 6mm long

centrifucation of ___ at RCF of ____

5 minutes; at RCF 10,000 to 15,000g