Coags Flashcards
Virchows triad
3 possible settings of thrombus formation
Hypercoagulable
Vascular wall injury
Circulatory stasis
How far in advance should heparin, aspirin, warfarin, nsaids, and plavix be stopped?
H 1-2 days
A 7 days
W 2-4 days
NSAIDS- 1-2 days
P 5-7 days
What percent of PTT is due to heparin?
50% or less
Protamine sulfate dose
1mg per 100u heparin
Dose drops over hours to .5 mg per, .25mg per
SLOW 3 minutes
When can I restart heparin after surgery?
24 if low risk
48 if high risk
DOACs names
Rivaroxaban xarelto
Apixaban eliquis
Edoxaban
Andexxa high vs low dose
H- 800mg in 30 min, 8 mg /min 120 mins
L-400mg in 30 min, 4mg/min 120 mins
Warfarininterferes with which factors
2
7
9
10
Warfarin antidote
Vit k but it takes 24h
Intracranial hemmorhage in thrombolytics risk rate
1%
Who needs bridge therap after surgery?
Pt on warfarin who are very high risk- mechanical valve, recent stroke 3 months, VTE 3 months
P2Y12 inhibitors
Platelet aggregation inhibitors (top of cell which starts whole process)
Clopidogrel (plavix)
Prasugrel
Ticagrelor (brilinta) (reversible)
Cangrelor (reversible)
COX inhibitors
Prevents platelet aggregation
Prevents ADP/ TXA2 activation at top of cell, prevents CA inside the cell, prevents the breakdown of AA - > TXA2
COX specifically stops AA to TXA2
Aspirin
GP2B/3A inhibitors
Platelet aggregation inhibitors (holding hands)
Abciximab
Eptifibatide
Tirofiban (aggrastat)
Anti platelets
P2Y12 inhibitors (top of cell)
COX inhibitors (AA to TXA12)
GP2B3A inhibitors (holding hands)
What coagulation factors does the liver make?
2,7,9,10- pro coagulants
C, S- anti coagulants
All are dependent on Vitamin K to make them functional
How common is heparin toxicity, and what are the signs?
1-10%
Bleeding
HIT (thrombocytopenia)
ABNM LFT
HIT signs and causes
Platelet under 100,000 or drop from baseline
1-15% risk, 5% with heparin flush, 10x lower with LMWH
5-15 days after treatment
Caused by antibodies
How to diagnose HIT
4Ts
Thrombocytopenia, timing of TCP, thrombosis, other causes of TCP
If score over 3, ELISA testing
SRA (serotonin release assays) is gold standard
HIT treatment
Stop heparin
Administer other anticoagulants
Add allergy to chart
Protamine sulfate?
DOACs
Direct acting anti coagulants on factor X (XA in name)
Apixiban (xarelto)
Rivoroxiban (eliquis)
Edoxaban
—
Direct thrombin inhibitors
dabigatran
argatroban
bivalruden
Anticoagulants and anesthesia
DOAC- d/c doac 4-5 days, but dabigatran is 3-5 days, restart 24-72 h after procedure depending on risk level
When can u give activated charcoal when bleeding? what med
Dabigatran DOAC
But the antidote is idarucizumab and ciraparantag
VKAs
Warfarin 2 7 9 10
What naturally prevents platelets
NO
PG
Protein C, S
Fibrinolytics
Clot busting- increases plasminogen to plasmin to break down fibrin, and break down fibrinogen so they dont hold clots together
Alteplase
reteplase
tenecteplace
streptokinase
urokinase
When are thrombolytics used
PE
DVT
clot on IV catheter
Acute MI
How long do fibrinolytics last?
7-24h post d/c
Who is at risk for sodium citrate toxicity?
hypothermia, liver/kidney pt, hypocalcemia
Anti coags that can stop factor 10 and 2
Via AT3 -Heparin, LMWH, fondaparinux
DOACs- xa- Apixiban (xarelto)
Rivoroxiban (eliquis)
Edoxaban
Direct thrombin inhibitors
dabigatran
argatroban
bivalruden
Which are good for arterio vs venous
Artery- anti platelet
Venous-
Both- anti coagulants
ACS treatment
Aspiring COX
P2Y12 Plavix
GP2B3A tirofiban (aggrastat) maybe
Heparin anti coag
ASA risks with use
PUD
Liver dmg <19yo reye syndome
Asthma exacerbation
What can inhibit CYP450 and for what drug does it matter
Warfarin
PAAAM
PPI
Amio
Azoles
Acetaminophen
Macrolides
CYP450 inducer drugs
Important for warfarin
C arbomazepine
P phenytoin
R ifampin
Hematology teratogenic drug
Warfarin
Minor vs major bleeding after hem drugs
minor- epistaxis (minimal), bleeding from wound, gingival,
major- GI bleed, massive uterine bleeding, cereberal hmg, hemothorax, hemopericardium
Hem reversal agents
APA- desmopressin
Heparin- protamine sulfate
DOACs- Xa- andexxa, 4-factor PCC (2,7,9,10)
Thrombin inhibitors- idaracizumab (reverse dabigatran)
What does andexanet alpha reverse
DOAC 400/4mg/min 800/8g/min
Thrombolytic major risk and %
Hemmorhage 2-4%
ICH 1%
Anti coagulants
Block factor 10 (and 2) in coagulation cascade
Blocks via AT3
Heparin
LMWH
Fondaparinux
LKW limits for thormbolytics
TPA- 3-4 hours
What lab to monitor for heparin and LMWH
H- aptt and anti xa
L- aptt and anti xa
