Blood Measurements

Question 1

What is Packed cell volume (PCV)?

Answer 1

This is the percentage volume of red blood cells present in a given sample of blood

Question 2

Packed cell volume is also called ____________

Answer 2

Hematocrit

Question 3

Hematocrit can be used to diagnose blood disorders such as

Answer 3

Anaemia
Hypoxia
Systemic ischemia

Question 4

______________ and _______________ are the methods for PCV determination

Answer 4

Wintrobe method
Capillary tube method

Question 5

What is hemostasis?

Answer 5

Stoppage of bleeding after a blood vessel is punctured, cut or damaged

Question 6

What are the stages of hemostasis?

Answer 6

Vasoconstriction
Platelet plug formation
Blood clot formation
Fibrinolysis

Question 7

What is Bleeding time?

Answer 7

Time interval between when a blood vessel gets punctured to when there is cessation of bleeding.

Question 8

What is clotting time?

Answer 8

Time interval from oozing of blood from an injury or puncture to the formation of clot

Question 9

What is the normal range for bleeding time?

Answer 9

3-6 minutes

Question 10

What is the normal range for clotting time?

Answer 10

3-8 minutes

Question 11

________________, ________________ and ________________ are methods of assessing bleeding time

Answer 11

Ivy’s method
Duke’s method
Simplate

Question 12

What are the methods of assessing clotting time

Answer 12

Venous blood clotting time
Capillary blood clotting time
Drop method

Question 13

_______________ and ______________ are the two important blood group determination systems

Answer 13

ABO
RH (Rhesus)

Question 14

What is the clinical importance of knowing blood groups?

Answer 14

Important for blood transfusions and tissue transport
Used for settling parental disputes in medicolegal cases

Question 15

_____________, ______________ and ______________ are reagents used in the estimation of prothrombin time

Answer 15

Plasma samples
Thromboplastin
Calcium chloride 0.025m

Question 16

Thromboplastin used in the estimation of prothrombin time is obtained from ____________________

Answer 16

Human or rabbit brain tissue

Question 17

Outline the method of prothrombin time estimation

Answer 17

A 75*10mm tube is placed in a water bath at 37°C
0.1ml of plasma is deposited inside
0.1ml of thromboplastin is added after 1 minute delay
0.1ml of calcium chloride 0.025m is added and the mixture is carefully mixed
Submerge lower end of the tube and start stopwatch
Fibrin clot formation marks the end point

Question 18

Normal range for prothrombin time is about ______________

Answer 18

10 to 14 seconds

Question 19

What is Erythrocyte sedimentation rate?

Answer 19

This is the rate at which red blood cells settle in a collected blood sample

Question 20

Why do RBCs settle at the bottle of a blood sample instead of plasma?

Answer 20

This is because RBCs have a greater specific gravity than that of Plasma

Question 21

2 factors affecting velocity of ESR

Answer 21

Sedimentation rate is directly proportional to the size of RBCs
Sedimentation rate is inversely proportional to the viscosity of plasma
Increased rouleaux formation rate increases sedimentation rate

Question 22

ESR is used to ____________

Answer 22

Measure progress of chronic diseases e.g. Rheumatism, tuberculosis.

Question 23

Normal range of ESR in males is ___________

Answer 23

0-5mm/hr

Question 24

Normal range of ESR in females is ___________

Answer 24

0-7mm/hr