Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Coagulation > Coagulation Testing > Flashcards

Coagulation Testing Flashcards

1
Q

Clotting End Point

A

Photo-optical
Electromechanical
Chromogenic
Immunologic

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

Photo-optical

A

Most Common
Measure change in optical density

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

Electromechanical

A

Clot completes the circuit
Clot impedes movement of steel ball

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

Chromogenic

A

Use of synthetic substrate
- Mimics natural counterpart
- Subtrate is linked to color indicator
- P-nitroanilide (yellow color)

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

Immunologic

A

Detection/measurement by antigen-antibody
- Electrophoresis
- Latex agglutination
- RID
- EIA

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

Prothrombin Time (PT)

A

Function of Extrinsic & Common Pathway
Factors: 7, 10, 5, 2, 1

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

PT Normal Time

A

12-15 seconds

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

PT Clinical Correlation

A

Prolonged
- Liver disease
- Vitamin K deficiency
- Factor deficiency of 1, 2, 5, 7, or 10
- Anticoagulatns
- DIC (Disseminated Intravascular Coagulation)

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

Activated Partial Thromboplastin Time (APTT)

A

Tests function of Intrinsic and Common Pathways
Factors: 12, 11, 9, 8, 10, 5, 2, 1

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

APTT Reagent

A

Phospholipid (PF3)
Contact activator (Silica, ellagic acid, kaolin)
CaCl2

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

APTT Normal Time

A

25-35 seconds

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

APTT Clinical Correlation

A

Prolonged
- Liver disease
- DIC
- Factor deficiencies: 12, 11, 9, 10, 5, 2, 1
- Anticoagulants

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

Thrombin Time (TT)

A

Thrombin added to plasma
Testing Factor 2

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

TT Normal Time

A

15-19 seconds

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

TT Clinical Correlation

A

Prolonged
- Hypofibrinogenemia
- Dysfibrinogenemia
- DIC
- Liver diease
- Increased FSP
- Heparin

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

Fibrinogen Assay

A

Determines amount of Factor 1 (fibrinogen)

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

Fibrinogen Assay Testing

A

Plasma diluted 1:10 with veronal buffer
Thrombin reagent added

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

Fibrinogen Normal Amount

A

200-400 mg/dl

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

Fibrinogen Clinical Correlation

A

Decreased amounts in:
- Liver disease
- DIC
- Fibrinogen deficiencies

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

FSP/D-Dimer Testing

A

Determines amount of FSP or D-Dimers present
Latex agglutination testing
- Visible agglutination above normal range

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

FSP (Fibrin Split Products) Normal Range

A

0-0.5 ug/mL or <400 ng/L

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

FSP Increased fibrinolysis Condition

A

DIC
Primary fibrinolysis
Pulmonary embolism

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

FSP Decreased or Incomplete Condition

A

Liver Disease

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

False Increase to Clotting Times

A

Hematocrit >55%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Unreliable Clot Times
Hematocrit <25%
26
Specimen Anticoagulant
Sodium Citrate 1:9 of citrate:blood Chelates Calcium
27
Adjustment for Hematocrit Calculation
(0.5 x (100-patient hct))/60
28
Testing Correction with Normal Plasma
Mix equal volumes of Pooled Normal Plasma (NP) to patient plasma Correction: within 2 sec PT within 5 sec APTT
29
Correction with NP
Consistent with Factor deficiencies
30
No/Partial Correction with NP
Consistent with presence of circulating anticoagulants - Heparin, Coumadin, FSPs, Lupus Inhibitor, Factor Inhibitors
31
Testing Correction with Saline
Mix with equal volumes of Normal Saline and Patient Plasma Correction: within 2 sec of PT or within 5 sec of APTT
32
Full/Partial Correction with Saline
Consistent with presence of circulating inhibitors
33
No Correction with Saline
Consistent with Factor deficiencies
34
Correction with NP, No with Saline
PT prolong, APTT normal - Possible Factor 7 PT normal, APTT prolong - Possible deficiency of PK, HMWK, 12, 11, 9, 8 PT prolong, APTT prolong - Deficiencies of any factor(s)
35
Pre Kallekrein Screening
Repeat APTT with increased incubation time - Allows for more contact activation - If correction is seen, evidence of deficiency
36
Pre Kallekrein Followup Test
PK Assay
37
Factor VIII:c Inhibitor
Most Common specific inhibitor
38
Reasons for 8:c Inhibitor
Hemophiliacs Drugs Post partum women Autoimmune disease Lymphoproliferative disease Unknown
39
Clinical Signs of 8:c Inhibitor
No response to therapy Severe bleeding Hemarthrosis (bleeding into joints)
40
Laboratory Signs of 8:c Inhibitor
Increased APTT, normal PT Correction with NP at 0 hrs No correction with NP at 2 hrs * TIME AND TEMPERATURE DEPENDENT *
41
Bethesda Titer
Determine the strength of Factor 8:c inhibitor
42
Bethesda Test
Equal volumes patient plasma and NP Incubate for 2 hrs at 37 C Factor assay test to determine amount of residual 8:c
43
Other Specific inhibitors
Possible with any inherited factor deficiency Caused by exposure to factor through treatment Not time or temperature dependent
44
Heparin
Acts as co-factor with Antithrombin Makes Antithrombin 280x more effective Most common cause of prolonged APTT in hospitalized patients Monitored by Heparin assay, Xa assay, or APTT
45
Heparin Laboratory Signs
Prolonged APTT, PT, TT No Correction with NP Correction/partial with Saline
46
Heparin Correction Testing
Protamine sulfate Reptilase Time
47
Low Molecular Weight Heparin
Inactivates platelet bond with Xa and resists PF4 inhibition No interference with platelets or endothelial cells Less antigenic Laboratory monitoring not required
48
Coumadin (Coumarin or Warfarin)
Vitamin K antagonist Common cause of prolonged PT Monitored with PT and INR
49
Coumadin Laboratory Signs
Prolonged PT, APTT Correction with NP No Correction with saline
50
Fibrin Split Products (FSP)
Acts by complexing with fibrin monomers and preventing polymerization
51
FSP Laboratory Signs
Prolonged PT, APTT, TT No correction with NP Correction/Partial with saline
52
Lupus Inhibitor (Anticoagulant)
Second most common cause of prolonged APTT Antibody (IgM, IgG) directed against phospholipid Inhibits reagent in APTT testing
53
Lupus Inhibitor Causes
SLE Drugs Infections Lymphoproliferative Disease Unknown
54
Lupus Inhibitor Clinical Signs
No Bleeding problems Thrombosis Possible increased platelet aggregation
55
Lupus Inhibitor Laboratory Signs
Prolonged APTT No correction with NP Correction/Partial with Saline Correction with platelet Neutralization procedure
56
Tissue Thromboplastin Inhibition Test (TTIT)
Used for Lupus Anticoagulant (LA) PT with dilute thromboplastin (contains phospholipids) - LA will cause greater prolongation of PT Results are compared with normal control
57
TTIT Calculation
Dilute PT/Orig PT Ratio >1:3 is consistent with LA
58
Dilute Russell Viper Venom Time (RVVT)
Used in LA testing Dilute RVV + phospholipid + CaCl2 + patient plasma RVV directly activates X if dRVV is higher than normal control = evidence of LA
59
Test Results Consistent with Heparin
FSP - normal TT - corrected with protamine sulfate PNP - NA
60
Immunological Assays
Laurel Rocket PIVKA (Prothrombin Induced VItamin K Antagonist)
61
Laurel Rocket Assay
Antibody to factor in agar Serial dilutions of NP, Control plasma, and patient are electrophoresed Antigen/Antibody complex precipitate and are stained
62
Factors Tested Using Laurel Rocket
VWF:Ag VIII Ag IX Ag
63
PIVKA
Antibody to factor 2 in agar Patient plasma is adsorbed with barium carbonate to remove carboxylated factor 2 Adsorbed sample is electrophoresed
64
Reptilase Time (RT)
Snake venom - Bothrox atrox Clots fibrinogen in different way than thrombin
65
Increased RT Associated with
FSPs Dysfibrinogenemia Hypofibrinogenemia
66
RT Removes Interference
Heparin
67
Factor Assays
Reagents for PT or APTT Factor deficient plasma - contains 100% factor of all factors except for specific one Pooled Normal Plasma
68
Factor XIII (13) Assay
Not tested by PT or APTT 5M Urea or Clot Solubility Test
69
5M Urea or Cold Solubility Test
Patient Plasma + CaCl2 = clot Add 5M urea Observe clot for lysis Clot lysis within 24 hrs indicates <5% XIII activity or inhibitor
70
Factor Antigenic Testing
Determines AMOUNT of protein present, not activity
71
Stypven Time (ST)
Also called Russell Viper Venom Time (RVVT) Snake venom - Viper russellii Activates coagulation pathway at X, bypassing 7
72
ST Interpretation
Prolonged PT and normal ST = 7 deficiency Prolonged PT and ST = common pathway deficiency
73
Activated Clotting Time (ACT)
Screening test for coagulation system Whole blood clotting time (performed at bedside)
74
ACT Testing
Venous sample Tube contains silaceous earth
75
Normal Clot time with ACT
80-125 seconds
76
VIII: VWF:Rco
Determines activity of the VWF portion of factor 8 molecule Serial dilutions of normal plasma, control, and patient Dilution + ristocetin + reagent platelets Observe for platelet aggregation

Coagulation (6 decks)

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