coagulation disorders

Question 1

haemostasis

Answer 1

arrest of bleeding

Question 2

thrombosis

Answer 2

inappropriate formation of clots within vascular system

Question 3

bleeding

Answer 3

failure of blood to clot in response to appropriate stimulus

Question 4

stages of haemostasis

Answer 4

1. vessel spasm
2. formation of platelet plug
3. blood coagulation or development of insoluble fibrin clot
4. clot restriction
5. clot dissolution

Question 5

requirements of blood clotting process

Answer 5

platelets (produced in bone marrow)
Von Willebrand factor (generated in vessel endothelium)
clotting factors (synthesised in liver using Vit K)

Question 6

clotting factor I

Answer 6

fibrinogen

Question 7

clotting factor II

Answer 7

prothrombin

Question 8

clotting factor III

Answer 8

thromboplastin

Question 9

clotting factor IV

Answer 9

calcium

Question 10

clotting factor VIII

Answer 10

anti-hemophilic factor

if don’t have = haemophilia A

Question 11

intrinsic blood clotting pathway

Answer 11

disease within body triggers clot formation, vitamin K dependent

Question 12

extrinsic blood clotting pathway

Answer 12

external stimulus triggers blood clot

Question 13

terminal steps of blood clotting process

Answer 13

1. calcium, factors V and X, platelet phospholipids combine to form prothrombin activator
2. prothrombin activator converts prothrombin to thrombin
3. this causes the conversion of fibrinogen to fibrin strands which create the insoluble clot

Question 14

hypercoagulability states

Answer 14

increase risk of clot or thrombus formation in the arterial or venous circulations

caused by accelerated activity of coagulation system or increased platelet function

Question 15

conditions that create increased platelet function

Answer 15

atherosclerosis, diabetes, smoking, elevated blood lipids and cholesterol, increased platelet levels

Question 16

conditions that cause accelerated activity of coagulation system

Answer 16

pregnancy, peurperium (6 weeks after delivery), oral contraceptives, post-surgical state, immobility, congestive heart failure, malignant diseases

Question 17

arterial thrombi

Answer 17

associated with conditions that produce turbulent blood flow and platelet adherence

Question 18

venous thrombi

Answer 18

associated with conditions that cause stasis of blood flow with increased concentrations of coagulation factors

Question 19

coagulation defects

Answer 19

impaired synthesis of coagulation factors

hereditary disorders - hemophilia A and Von Willebrand disease

Question 20

conditions associated with disseminated intravascular coagulation

Answer 20

obstetric conditions, cancer, infections, shock, trauma and surgery, hematologic conditions

Question 21

disseminated intravascular coagulation

Answer 21

plenty of blood clots and blockages = tissue and organ death, but some bleeding occurring too

Question 22

hemophilia

Answer 22

inherited bleeding disorder in which there is a deficiency or lack of factor VIII (A) or IX (B)

Question 23

detection of hemophilia

Answer 23

family history, symptoms (bruising, bleeding after minor surgery, muscle/joint/soft tissue bleeding), lab testing, hemostatic challenges (surgery, dental work, trauma)

Question 24

types of bleeds

Answer 24

joint bleeding, muscle hemorrhage, soft tissue, life threatening and other

Question 25

Von Willebrand disorder

Answer 25

bleeding disorder - hereditary pseudohemophilia prolonged bleeding despite normal platelet count - VW factor deficiency

Question 26

platelet function

Answer 26

formation of mechanical plug during normal hemostatic response to vascular injury adhesion, activation and release, aggregation

Question 27

normal platelet count

Answer 27

250 000 uL life span 7-10 days

Question 28

platelet adhesion

Answer 28

platelet adheres to sub-endothelial collagen dependent on VW factor and glycoproteins

Question 29

platelet activation

Answer 29

changes shape and release chemical signals (ADP, serotonin, prostaglandins)

Question 30

platelet aggregation

Answer 30

stick to cells going past to form the plug

Question 31

causes of bleeding

Answer 31

decrease in number of circulating platelets or impaired platlet function

Question 32

scurvy causing bleeding

Answer 32

poor collagen synthesis and failure of endothelial cells to cement together = fragile wall

Question 33

cushing's disease causing bleeding

Answer 33

protein wasting and loss of vessel tissue support because of excess cortisol

Question 34

VW factor

Answer 34

role in anchoring platelets to site of injury and links exposed collagen to platelets function in hemostasis - protects factor VIII from proteolytic degradation and localised it to site of injury