Substitution tests

Question 1

Substitution test purpose

Answer 1

Identify factor deficiency, detect lupus anticoagulant, and specific factor inhibitors

Question 2

Fresh plasma in substitution test

Answer 2

Contains all coagulation factors except III and IV

Question 3

Aged plasma in substitution test

Answer 3

Contains all factors except V and VIII

Question 4

Aged serum in substitution test

Answer 4

Contains factors I, V, VIII, XIII, II

Question 5

Adsorbed plasma in substitution test

Answer 5

Contains all factors except Vitamin K dependent (II, VII, IX, X)

Question 6

Prolonged PT and aPTT

Answer 6

Missing coagulation factors in common pathway (I, II, V, X)

Question 7

Normal PT, prolonged aPTT

Answer 7

Missing intrinsic factors (VIII, IX, XI, XII)

Question 8

Prolonged PT, normal aPTT

Answer 8

Missing extrinsic factor (Factor VII)

Question 9

Stypven time (Russel’s Viper Venom Time) purpose

Answer 9

Detect deficiencies in fibrinogen, prothrombin, factors V and X

Question 10

Stypven time difference from PT

Answer 10

Factor VII deficiencies are not detected

Question 11

Coagulant used in Stypven time test

Answer 11

Russel’s viper venom from Vipera russeli