MICROHEMATOCRIT DETERMINATION

Question 1

Ratio of volume of RBCs to that of whole blood expressed as percentage or in ratios

Answer 1

MICROHEMATOCRIT DETERMINATION

Question 2

T or F
Microhematocrit is unreliable as an estimate of anemia

Answer 2

T

Question 3

Used only in the past; large amount of blood needed
Large error due to trapped plasma

Answer 3

Macrohematocrit Method of Wintrobe

Question 4

Macrohematocrit Method of Wintrobe:
Centrifugation at _____g for ___ mins

Answer 4

2,000-2,300 g
30

Question 5

Most accurate manual method

Answer 5

Microhematocrit Method of Adams

Question 6

Microhematocrit Method of Adams:
Centrifugation at:

Answer 6

5 minutes (10,000-12,000 x g)

Question 7

Microhematocrit Method of Adams:
Blood filled:

Answer 7

5cm (capacity of tube is 7.5cm)

Question 8

Microhematocrit Method of Adams:
Clay Seal/ Plug:

Answer 8

4mm

Question 9

Inadequate centrifugation

Answer 9

Falsely elevated

Question 10

Incomplete sealing

Answer 10

Falsely low

Question 11

Including buffy coat in the
measurement

Answer 11

Falsely elevated

Question 12

Trapped plasma (causes 1-3%
higher than value obtained in
automated analyzers)

Answer 12

Falsely elevated

Question 13

Macrocytic anemia

Answer 13

Falsely elevated

Question 14

Hypochromic anemia

Answer 14

Falsely elevated

Question 15

Sickle cell anemia

Answer 15

Falsely elevated

Question 16

Overanticoagulation (occurs in
underfilled tubes)

Answer 16

Falsely low

Question 17

V fluid contamination

Answer 17

Falsely low

Question 18

Interstitial fluid from a skin
puncture

Answer 18

Falsely low

Question 19

• Can be used to quickly check the results of Hgb and Hct
• Applies only to specimens that have normocytic normochromic RBCs

Answer 19

Rule of Three

Question 20

Rule of Three

Answer 20

Hgb x 3 = Hct (±3)