Prothrombin Time And Blood Grouos

Question 1

Test for

Answer 1

Extrinsic pathway which is common pathway for clotting

Question 2

Test steps

Answer 2

Sodium citrate prevents coagulation by precipitating calcium ions which is important for coagulation
Centrifuge and separate plasma
Thromboplastin and excess calcium ions is added to compensate for calcium ions precipitated by sodium citrate
Record clotting time

Question 3

Normal value

Answer 3

10 to 14 seconds

Question 4

Normal values in hemophilia

Answer 4

Prothrombin time is dependent on extrinsic pathway which is factors 2,5,7 and 10 while hemophilia types affect factor 4,6 and 8
Prolonged values in vitamin k deficiency which is needed for factors 2,5,7 and 10
Patients treated with dicoumarol which inhibits prothrombin formation in liver

Question 5

Percentage of different blood groups

Answer 5

Group O is 45%
Group A is 40%
Group B is 10%
Group AB is 5%

Question 6

Test importance

Answer 6

Blood grouping and cross matching before blood transfusion to avoid blood agglutination or complications of blood transfusion
Medico legal importance to exclude not prove paternity

Question 7

Test complications

Answer 7

Cause of agglutination is reaction between donors red cells and recipient plasma as it is more important than reaction between donors plasma and recipient red cells and donors antibody is diluted by recipient blood

Question 8

Patients requiring blood transfusion

Answer 8

Hemorrhage
Erythroblastosis fetalis
Severe anemia
Restore one element

Question 9

Test precautions

Answer 9

Compatible
Free of diseases
Fresh and stored from 0 to 21 days at -4 degrees Celsius

Question 10

Complications incompatible blood transfusion

Answer 10

Agglutination of blood
Blockage of capillaries causing joint pain, stoke and myocardial infarction
Intravascular hemolysis release histamine which cause vasodilation and shock
Vitamin k cause cardiac arrhythmia
Hemoglobin cause hemolytic jaundice and block renal tubules