Bleeding Disorders and Anti-Coagulation Flashcards
(178 cards)
1
Q
What are intentional bleeding disorders?
A
result of tx or prevention of a disease, ie just had a stroke, preventing another
2
Q
How are bleeding disorders acquired?
A
result of disease, side-effect of tx
3
Q
3 categories of why ppl bleed:
A
inherited, acquired, intentional disorders
4
Q
Phases of clotting;
A
vascular, platelet, coagulation (fibrinolytic)
5
Q
Phases of clotting we are concerned w:
A
platelet, coagulation,
6
Q
Bleeding can be instantaneous in these phases;
A
vascular and platelet phases
7
Q
When does bleeding occur int he coagulation phase?
A
min to hrs later
8
Q
coagulation phase is aka:
A
fibrinolytic phase
9
Q
Pts can have issues in this phase of clotting after they leave the office:
A
coagulation phase (fibrinolytic)
10
Q
When does the vascular phase begin?
A
immediately after injury
11
Q
What happens during vascular phase?
A
vessels constrict and retract, fluid pressure from blood collapses adjacent vessels
12
Q
What meds can affect the vascular phase?
A
none
13
Q
When does the platelet phase begin?
A
secs after injury
14
Q
What makes platelets sticky?
A
exposure of endothelial tissues, platelet plug seals site
15
Q
How long does the coagulation phase take?
A
10-20m
16
Q
Via which pwy(s) does blood in surrounding tissue coagulate?
A
both extrinsic and common pwys
17
Q
Via which pwy(s) does blood in vessels coagulate?
A
both intrinsic and common
18
Q
Intrinsic pwy:
A
(APPT) kininogen/ kallikrein, FXIIa, FXIa, FVIII (?), FXa, Thrombin, Fibrin
19
Q
Extrinsic Pwy:
A
(PT) FVIIa, FX, FXa, Thrombin, Fibrin
20
Q
Common Pwy:
A
X, Prothrombin, thrombin, fibrinogen, Fibrin
21
Q
Partial Thromboplastin Time measures which pwy>?
A
Intrinsic
22
Q
Prothrombin Time measures which pwy?
A
extrinsic pwy
23
Q
How to measure from fibrinogen to fibrin?
A
thrombin time
24
Q
All pwys end w formation of:
A
fibrin
25
Factors assoc w common pwy:
X, V, II, Fibrinogen, Fibrin
26
What activates the intrinsic pwy?
surface activation
27
What activates the extrinsic pwy?
tissue thromboplastin
28
Problems w vascular phase;
usually non-specific, confined to skin, mucosa and gingiva, petechiae, ecchymosis, purpura, aging, Cushing';s syndrome, collagen disorders, Vit C deficiency
29
How can Cushing's syndrome lead to non-specific minor bleeding problems?
high dose exogenous steroids
30
Collagen disorder related to CV defects and excessive growth:
Marfan
31
Lits 2 collagen disorders:
Marfan, Ehler-Danlos
32
Congenital platelet disorders, rare or common?
rare
33
Types of acquired thrombocytopenia:
Idiopathic, Immune
34
Types of immune thrombocytopenia:
lupus, HIV
35
What is thrombocytopenia?
low platelet count
36
ITP sf:
Idiopathic thrombocytopenia
37
Type of thrombocytopenia that can be cyclic:
idiopathic
38
Normal platelet count:
150,000-400,000/microL
39
Platelet count necessary for major surgery:
80,000
40
Platelet count necessary for minor surgery:
50,000+
41
At risk for spontaneous bleeding if platelet count is below:
20,000
42
TF? A pt will most likely not clot if their platelet count is ½ of low/normal.
F. probably will
43
How can a surgical proc be performed on a pt w low platelet count?
Call hematologist, use exogenous blood products
44
Thrombocytopenia can result from;
aplastic anemia, leukemia, bone marrow suppression (chemo), kidney disease
45
Is a platelet count needed for a pt who had chemo mos ago?
yes
46
TF? With platelet dysfunctino, the platelet count is normal.
T
47
Causes of platelet dysfunctino:
dialysis, meds
48
meds that can cause platelet dysfunction:
ASA, NSAIDS, platelet aggregate inhibitors
49
Why can dialysis lead to platelet dysfunction?
it damages platelets
50
Drugs that effect platelet aggregation:
aspirin, non-steroidals, plavix
51
How to test for platelets?
platelet count, platelet function tests
52
4 Platelet function tests:
closure time assay, viscoelastometry, Platelet aggregometry, flow cytometry (bleeding time)
53
Superficial wound healing is mainly about:
platelets
54
Platelet function test that is no longer done:
bleeding time
55
Coagulation phase disorders:
hemophilia A and B
56
Hemophilia A:
Factor VIII deficiency (intrinsic pwy)
57
hemophilia B:
Factor IX deficiency (intrinsic pwy)
58
hemophilia B is aka:
Christmas disease
59
Other factor deficiencies;
IX, X, XI, XII
60
TF? There are no factor deficiencies affecting the extrinsic pwy.
T. check (only 8-12)
61
Meds are most likely to effect which phase of clotting?
coagulation phase
62
hereditary disorder that effect platelet adhesion and FVIII:
Von Willebrand's, hereditary blood clotting disorder
63
How many types of Von Willebrand's are there?
4
64
Is Von Willebrand's usually serious?
no
65
Tx for Von Willebrand's;
nasal meds
66
Most severe type of Von Willebrand's:
Type 3, low FVIII
67
Acquired coagulation phase bleeding disorders:
Liver disease, meds, DIC
68
Factors involved w Vit K dependent, acquired bleeding disorder;
II, VII, IX, X
69
Where are Vit K dependant factors produced?
liver
70
Prevalence of alcoholism:
5%
71
Medical/ intentional anticoagulation:
recent MI, CVA (stroke), Thromophlebitis, Atrial fibrillation, pulmonary emboli, Deep vein thrombosis, Thrombogenic implanted devices
72
Drugs used to thin blood:
platelet aggregate inhibitors, Heparin, Low molecular weight heparins, Coumadin, New Xa inhibitors
73
Ex of platelet aggregate inhibitors:
ASA, Plavix, Persantine, Aggrenox, NSAIDs
74
Ex of Low molecular weight heparins:
Lovenox, Normiflo, Sandoparin
75
What does Plavix do?
inhibits ADP-induced platelet aggregation
76
Plavix is used to treat;
recent MI, stroke, established peripheral artery disease
77
Plavix is aka;
clopidorgel bisulfate
78
How many mg is a baby aspirin:
81mg
79
All pts taking Plavix are also taking:
Aspirin
80
When are platelet aggregate inhibitors used?
if pt can't tolerate ASA or in conjunction w ASA
81
ASA sf:
acetylsalicylic acid
82
NSAIDs may increase:
GI Bleeding
83
When to discontinue the use of platelet aggregate inhibitors:
only for major surgery
84
How long to discontinue the use of platelet aggregate inhibitors for major surgery:
7-10d prior to surgery
85
Why must platelet aggregate inhibitors be discontinued 7-10d prior to major surgery?
life span of the palatelet
86
What to ask pt on platelet aggregate inhibitors:
nosebleeds? Hard time stopping bleeding if you get minor cuts? spontaneous gingival bleeding?
87
Is Heparin available in oral form?
no, IV, subcutaneous injection
88
1/2 life of Heparin:
2-4h (short)
89
When is Heparin used?
inpatient basis, dialysis
90
How are the intrinsic and common pwys measured?
Partial Thromboplastin Time (PTT)
91
Drug of choice to anticoagulate briefly:
Heparin
92
Pts we can not see:
just had dialysis, drunk, 180 S BP, Dr lowered their Coumadin yesterday bc their INR was 6, ADA says INR above 4 provided local hemostatic measures are used, everyone else says INR under 3 is safe, Pt taking different doses of Coumadin throughout week bc they can’t stabilize pt, pt has blood coumadin levels checked weekly
93
Heparin is connected to this pwy and this test:
intrinsic and common pwy, PTT
94
How are Low molecular weight heparins delivered?
injection, themselves or PCP
95
What type of dug is Lovenox?
Low molecular weight heparin
96
When are Low molecular weight heparins most commonly used:
temporarily or bridging bw different meds, ie Weaning off coumadin for surgery but want to protect pt in the meantime, at risk or 4h vs. 4d
97
This is a structural analog of Vit K:
Coumadin (Warfarin)
98
TF? Coumadin is available in injectable form.
F
99
What does coumadin inhibit?
Vit K dependent synthesis of factors II, VII, IX, X in the liver (extrinsic, INR)
100
Which pwy and test is coumadin assoc w?
extrinsic, INR
101
Issue w Coumadin:
hard to titrate, rebound effects, hypercoagulable, hard to regulate
102
1/2 life of Coumadin:
active 2-3d after dose
103
When to discontinue Coumadin:
ONLY Inpatient, should never need to do, discontinue for 3d, treat on 4th
104
INR sf:
international Normalized Ratio
105
INR standardized:
PT values across labs (extrinsic pwy)
106
What does INR measure:
extrinsic and common pwy
107
elevated INR cold indicate:
severe liver disease w related bleeding
108
Normal INR value, healthy person not on meds
1
109
Therapeutic range for most condiitons EXCEPT valve replacement:
2-3
110
Threapeutic range for pts w valve replacements
2.5-3.5
111
Don't work on a pt if their INR value is:
4.5+
112
Most condition that ppl are on coumadin for want INR values of:
2.0-3.0 (therapeutic range)
113
INR value of 1.8, more or less likely to bleed?
less
114
Should coumadin levels be inc or dec of the pts INR value is 1.8?
inc
115
What does it mean if a drug has interactions w Aspirin?
it is very likely to have many other interactions
116
Interaction between two or more drugs or agents resulting in a pharmacologic response greater than the sum of individual responses to each drug or agent:
potentiation
117
Coumadin can interact via potentiation w these drugs:
ASA, acetaminophen, COX-2 inhibitors (osteoarthritis), penicillin, erythromycin, Tetracycline, cephalosporins, Fluconazole, Vitorin, Lexapro, Paxil, Zoloft, Effexor, Nexium, Prevacid, Protonix, Ultram
118
COX-2 inhibitors are sed to treat:
osteoarthritis
119
Coumadin can interact via antagonization w these drugs:
Barbiturates, steroids, ascorbic acid, dicloxicillin
120
Most important factor effecting anticoagulation and effects of Coumadin.
Diet, Vit K, esp leafy green veggies
121
Ask pts taking Coumadin this:
any changes in diet lately
122
When to stop Coumadin before dental proc:
never
123
Before doing dental proc we should:
verify INR is in therapeutic range
124
TF? Coumadin is volatile in terms of effects,
T
125
Which is more dangerous to do in terms of bleeding SRP or simple single tooth extraction?
SRP (perio procedure)
126
How recently should the last INR have been taken?
depends, # of proc sites, soft or bony tissue, stability of pt, freq of blood draws, dosage change, complications
127
INR has been the same level for years and been on the same dosage for years, accept INR value from
3mo ago (pushing it)
128
Level of pt stability if they have Coumadin levels checked every 4wk:
moderately stable
129
Level of pt stability if they have Coumadin levels checked every 12wk:
stable
130
If doctor recently changed Coumadin levels, you need an INR value within:
the last day
131
If a pt is changing Coumadin levels but needs an extraction, when should you schedule the extraction?
Day after next INR test
132
TF? Coumadin should be discontinued 7-10d prior to dental treatment
F. don't discontinue
133
INR 4 indicates:
overmedicated
134
Why don't we stop Coumadin:
excessive bleeding in mouth is detectable and stoppable, risk of bleeding to death is much lower than risk of throwing a clot and having a serious medical condition (stroke, death), initial start of Coumadin makes pt hypercoagulable in short term, very difficult to re-establish stable levels for some
135
Chance of bleeding to death in western society:
very low
136
What leads to the hypercoagulable state w initial restart fo Coumadin?
affects protein C and protein S, both natural anticoagulants
137
Eliquis, Xarelto xaban moa:
Factor 10a inhibitors (prothrombin to thrombin)
138
These are both natural coagulants:
Protein S, Protein C
139
MOA of Pradaxa:
acts a little further down cascade than Factor Xa, direct Thrombin inhibitor (IIa)
140
New Anticoagulants:
Eliquis, Xareltoo, Pradaxa
141
FII:
Prothrombin
142
FIIa:
Thrombin
143
FVIIIa is used to:
convert soluble fibrin monomers to insoluble fibrin polymers
144
Extrinsic and INtrinsic pwys meet at this point of the cascade:
FXA
145
Problem w Xa inhibitors:
don't know current numbers or how likley they are to bleed, no blood test
146
Higher bioavailability, Coumadin or Xa inhibitors.
Xa inhibitors
147
% of Xa that will be active in a persons body at any age:
90%
148
1/2 life of Xa ihibitors:
5-19h, good fo daily dosing
149
When to schedule pt taking Xa inhibitors if they take meds at night:
late afternoon, as little in their system as possible
150
Benefits of Xa inhibitors:
predictable pharmokinetics, no routine monitoring, high bioavailability, 1/2 life that works well w daily dosing
151
Bioavailability of Coumadin:
25-75% (varies w age, ethnicity, health status group)
152
What is the reversal agent for Xa inhibitors.
NONE
153
TF? Eliquis has a reversal agent.
F. in the works
154
TF? Xarelta has a reversal agent.
F. in the works
155
TF? Pradaxa has a reversal agent.
T. idarucizumab
156
Eliquis should be discontinued at least ___ prior to elective surgery or invasive proc w LOW risk of bleeding or where bleeding would be non-critical in location and easily controlled. (All dental proc)
24h
157
How long to discontinue Eliquis prior to elective surgery or invasive procedures with a MODERATE OR HIGH risk of unacceptable or clinically significant bleeding.”
at least 48hr
158
If anticoagulation must be discontinued to reduce risk of bleeding with surgical or other procedures, Xarelto should be stopped at least ___ before the procedure…
24hr
159
If possible, discontinue PRADAXA ___ (CrCL>150ml/min) or ____ (CrCl < 50 ml/min) before invasive or surgical procedures because of the increased risk of bleeding…
1-2 days, 3 to 5 days
160
What does, how long before surgery discontinuation of Pradaxa should begin?
creatinine clearance (kidney function
161
What does whether or not to discontinue anticoagulants for simple surgical proc depend upon?
If pt is at high or low risk for thromboembolism (time daily dose after proc or skip 1d)
162
Factors that inc risk of thromboembolism:
Recent deep vein thrombosis, or pulmonary embolism (w/in 3mo), High-risk prothrombotic condition (protein C or s deficiency), high risk prosthetic valve (caged-ball or tilting disk), high risk atrial fibrillation (CHADS score 5-6), atrial fibrillation w rheumatic heart disease, recent stroke from atrial fibrillation or heart valve (w/in 6mo)
163
What to ask PCP is pt is taking Eliquis:
My pt is on Eliquis, we want to extract 2 teeth, what do you recommend?
164
TF? If on XA inhibitor we must contact physician if doing invasive procedure.
T
165
For the new anticoagulants (Pradaxa, Eliquis, Xaralto) should we consult the PCP?
yes
166
Should we contact the PCP for pts w Hemophelia/ Von Willebranads disease?
contact hematologist, might need factor augmentation, DDAVP, local measures
167
What does DDAVP do?
slows amount of urine kidneys make, vasopressin replacement
168
Steps to take for pt w liver disease:
Contact PCP and ask for INR, Platelet count, local measures?
169
Steps to take for pt taking Coumadin:
INR? (how recent?), local measures
170
Local hemostatic measures:
Atraumatic surgical technique, sutures, direct pressure
Gelatin sponges “Gelfoam” placed in socket, cellulose polymer- “Surgicel” placed in socket, vasoconstrictors in LA, tranexamic acid (read about, but he’s never used, mouthrinse hemostatic props), topical thrombin (placed directly on wound, available in clinic)
171
Local hemostatic measure we have in clinic:
topical thrombin
172
Only coagulant meds that you might discontinue:
Xeralto, Eliquis
173
Pwy that Heparin and Lovenox both work on and test:
intrinsic, PTT
174
Pwy Coumadin works on and test:
extrinsic (INR)
175
Test for Xeralto and Eliquis:
non (Xa inhibitors)
176
Test for ASA, Plavix:
Platelet function test (rarely done)
177
Injectable only anticoagulants:
Heparin, Lovenox
178
What to do if platelet fxn test is too low for ASA and Plavix pts:
defer or transfuse
