Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

J Haem > Haemostasis > Flashcards

Haemostasis Flashcards

1
Q

is platelet plug formation primary or secondary haemostasis

A

primary haemostasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

is fibrin clot formation primary or secondary haemostasis

A

secondary haemostasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what injuries is platelet plug formation good for

A

small bleeds eg nose bleed, small cut

bc primary haemostasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what injuries is fibrin clot formation good for

A

larger bleeds

bc secondary haemostasis and platelet plug formation isn’t sufficient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how long is platelet lifespan

A

7-10 days

so need to stop antiplatelet (eg aspirin) 1 week before surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

first stage in platelet plug formation

A

endothelial damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is exposed after endothelial damage

A

collagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what factor is released bc of endothelial damage

A

von Willebrand factor (vWF)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what does exposed collagen and von Willebrand factor attract to endothelial damage

A

platelets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

once platelet adhesion at site of endothelial damage has occurred, what happens

A

platelet aggregation (more platelets come) = platelet plug formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

after platelet plug formation, what happens if insufficient to stop bleeding

A

fibrin clot formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

which clotting factors are attracted to platelet plugs to form a fibrin clot (8)

A 
tissue factor 
factor II (prothrombin) 
factor V 
factor VII 
factor VIII 
factor X 
factor IX

also fibrinogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

factor II

A

prothrombin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

factor IIa (activated factor II)

A

thrombin (activated prothrombin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

which clotting factors initiate V/Xa (and hence initiate fibrin clot formation)

A

TF/VIIa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

which clotting factors activate prothrombin (II) to thrombin (IIa)
via the production of which enzyme

A

V/Xa (most important ones, have central role)

via production of prothrombinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what does activation of thrombin (IIa) from prothrombin (II) cause (2)

A

conversion of fibrinogen to fibrin (to make fibrin clots) activation of VIII/IXa (which goes on to amplify V/Xa etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what does activation of VIII/IXa by thrombin cause

A

amplification of V/Xa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

which part of the fibrin clot formation system is classed as the ‘common’ pathway

A

from V/Xa onwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

which part of the fibrin clot formation system is classed as the ‘intrinsic’ pathway

A

VIII/IXa

XIIa converting XI to XIa combining with FVIII to convert IX to IXa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

which part of the fibrin clot formation system is classed as the ‘extrinsic’ pathway

A

TF/VIIa

THINK: extrinsic bc TF comes from tissue damage (external factor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

by what process are fibrin clots normally broken down (normal part of haemostasis)

A

fibrinolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

products of fibrinolysis

A

fibrin degradation productions (FDPs)

aka d-dimers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what substance is needed to break down fibrin clots to fibrin degradation products

A

plasmin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
how is plasmin made from plasminogen
tissue plasminogen activator (tPA)
26
what are the 2 natural anti coagulant defences used to ensure normal haemostasis
anti-thrombin | protein C and protein S
27
how does antithrombin work as anti coagulants
switches off thrombin directly = anti coagulant also switches off clotting factors = indirectly switches off thrombin
28
how does protein C and protein S work as anti coagulants
decrease factor V/Xa and VIII/Ixa =decreased thrombin production ie switches off thrombin indirectly
29
presentation of failure of platelet plug formation (primary haemostasis problem)
easy bruising nose bleeds purpura of lower limbs - non blanching rash menorrhagia
30
which type of haemostasis is lacking if failure of platelet plug formation
no primary haemostasis
31
how do steroids cause primary haemostasis
decrease collagen in vessel walls
32
what is the problem in Henoch-schonlein purpura who gets it
antibodies to vessel walls = primary haemostasis problem hence present with purpura) occurs in children
33
which congenital MSK condition presents with primary haemostasis failure why
marfans bc collagen deformity = decreased platelet plug formation
34
what are the 3 sources of problem that could cause primary haemostasis problems
vessel problem - eg marfans, steroids, Henoch schonlein purpura platelet problem - reduced number von Willebrand factor deficiency
35
what can cause reduced number of platelets (= primary haemostasis problem) (7 in total, 3 categories)
reduced platelet production - bone marrow cancer, alcohol increased platelet destruction - DIC, immune thrombocytopenic purpura (ITP), hypersplenism reduced platelet function - antiplatelet drugs eg aspirin, renal failure
36
haemostasis problem in alcoholics
probs primary and secondary primary haemostasis failure - bc alcohol is toxic to bone marrow = decreased platelet production secondary haemostasis failure - if liver failure = decreased clotting factor activation
37
which autoimmune condition can cause increased platelet destruction = primary haemostasis problem what is the problem
immune thrombocytopenic purpura (ITP) antibody produced against platelets = increased destruction
38
treatment of ITP causing primary haemostasis
immunosuppression prednisolone (bc autoimmune thing)
39
why does hypersplenism cause primary haemostasis
platelets are removed by the spleen so hypersplenism = increased platelet removal from circulation
40
most common inherited bleeding disorder | does it cause primary or secondary haemostasis problem
von Willebrand factor deficiency causes primary haemostasis problem (no platelet plug formation)
41
vWF deficiency inheritance pattern
autosomal dominant
42
which pathway isn't working (intrinsic or extrinsic) in vWF deficiency hence which 'time' is prolonged
intrinsic pathway not working need platelet plug formation to occur to allow VIII to bind APTT prolonged
43
presentation of failure of fibrin clot formation (secondary haemostasis problem)
delayed muscle bleeding | serious delayed post traumatic bleeding
44
investigations for primary haemostasis problem
platelet count if low = reduced production/increased destruction, need to do bone marrow aspiration to figure out which if high = reduced function/vascular problem/vWF deficiency
45
why do you want to do fundoscopy once primary haemostasis problem diagnosed
for retinal haemorrhages
46
causes of failure of fibrin clot formation (5 causes, 2 categories)
single clotting factor deficiency - haemophilia A, haemophilia B multiple clotting factor deficiency - DIC, liver failure, vit K deficiency
47
do males/females get haemophilia
males (X linked)
48
is haemophilia A or B more common
haemophilia A
49
clotting factor VIII deficiency
haemophilia A | bc A is before B and VIII is before IX
50
clotting factor IX deficiency
haemophilia B | bc B is after A so IX is after VIII
51
Christmas disease
another name for haemophilia B
52
in haemophilia, what happens if you have a small cut
will heal fine - bc still got platelet plug formation
53
in haemophillia, no factor VIII/IX causes no factor … which causes ...
factor X = cant make fibrin
54
presentation of haemophilia | at what age
``` haemarthrosis - spontaneous and prolonged bleeding in joints (knee, ankle, elbow) in toddlers (not babies bc not crawling) ```
55
v painful bleeding into knee joint
haemarthrosis | occurs in haemophilia
56
management of haemophilia A
IV factor VIII every 2-3 days, self administered
57
management of haemophilia B
IV factor IX every 2-3 days, self administered
58
APTT and PT in haemophilia
``` APTT prolonged (abnormal extrinsic pathway VIII/IX) PT normal (normal intrinsic pathway TF/VII) ```
59
how do you differentiate between haemophilia A and B if both prolonged APTT but normal PT (which investigation)
clotting factor assay
60
3 causes of multiple clotting factor deficiency
vit K deficiency DIC liver failure eg alcoholics (may present with primary haemostasis problem too bc of toxic effect of alcohol on bone marrow = decreased platelet production)
61
why does liver failure cause multiple clotting factor deficiency
clotting factors are made in the liver :(
62
which vitamin is needed for activation of clotting factors (hence deficiency causes multiple clotting factor deficiency)
vitamin K
63
causes of vitamin K deficiency
poor diet - is in leafy veg malabsorption neg chrons warfarin - is a vit K antagonist newborn (none acquired in diet yet so need IM vit K)
64
what does vit K deficiency in babies cause (if you don't give IM vit K after birth)
haemorrhagic disease of the newborn
65
which clotting factors does vit K activate
II, VII, IX, X KNOW THIS!!
66
causes of DIC
RTA sepsis obstetric emergencies malignancy lots of things - tbh any cause of bleeding
67
what is there an increase of in DIC = causes the problem
excessive platelet plug formation also lots of TF release = overactivation of haemostasis = use up other clotting factors = none left
68
presentation of DIC
'bleeding from everywhere' eg venflon holes, colostomy sites bruising, purpura and generalized bleeding (bc primary and secondary haemostasis problem)
69
PT and APTT in DIC
APTT prolonged | PT prolonged
70
vit D deficiency PT and APTT
APTT prolonged | PT prolonged
71
how do you differentiate between vit K deficiency and DIC as cause of prolonged APTT and PT
D-dimers increased in DIC | and presentation will differ !
72
management of DIC
``` treat underlying cause eg sepsis platelets and FFP (asap) fibrinogen replacement cryoprecipitate RBC transfusion if bleeding ```
73
what does a coagulation screen consist of
platelets APTT PT
74
PT prolongation | where is the problem
extrinsic pathway (TF/VIIa) problem THINK: extrinsic bc TF comes from tissue damage (external factor)
75
APTT prolongation | where is the problem
intrinsic pathway (VIII/IXa) problem THINK: Aptt = for All the many factors that contribute to VII/IXa (need XII, XI etc)
76
PT prolongation differentials (2)
DIC | vit K deficiency
77
APTT prolongation differentials (4)
DIC vit K deficiency haemophilia vWF deficiency (primary haemostasis problem but no VIII)
78
APTT prolonged PT prolonged what are the options (4)
DIC it K deficiency anticoags (warfarin) liver problem
79
increased d-dimers cause
fibrinolysis in DIC d-dimers = fibrillin degradation products (FDPs)

J Haem (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions