Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Perf Tech II (exam 2) > Topic 8 Management of postop bleeding > Flashcards

Topic 8 Management of postop bleeding Flashcards

1
Q

Heparin that becomes protein bound:

A

-Unavailable for reversal
-May become free post-CPB
“HEPARIN REBOUND”

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

Excess Protamine induces

A

Induce bleeding

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

Hemodilution what % decrease is there in circulating factors ?

A

Appx 25-35% decrease in circulating factors

Institution dependent

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

Sources of Post Op Bleeding (7)

A 
-Reduced concentration of coagulation
factors
-Hyperfibrinolysis
-Thrombocytopenia
-Impaired Platelet Aggregation
-Platelet Fragmentation
-Loss of Membrane Receptors
-Increased inflammation after CPB impairs
coagulation and increases blood loss
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Extrinsic Factor of Post Op Bleeding (4)

A
  • Residual Heparin / Heparin Rebound
  • Excessive Protamine
  • Hemodilution
  • Hypothermia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Prevention of Post-Op Bleeding

A
  • Avoiding CPB
  • Improved biocompatibility of foreign surfaces
  • Alter conduct of bypass
  • Use hematologic strategies
  • Harvest whole blood / Plasma/PRP
  • Improved surgical technique
  • Making sure labs are normal pre-op
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Heparin has mild fibrinolytic effect

A

-Stimulates release of serum urokinase
plasminogen activator (UPA)
-Induces fibrinolysis

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

Tissue Plasminogen Activator (TPA)

A

-More potent than UPA.
-Primary activator of fibrinolysis during
heart surgery.

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

Large surge of what after protamine is

given

A

TPA

At the time of greatest thrombin production

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

If left unchecked, could result in large scale
clotting or diffuse intravascular
coagulation.

A

TPA (i.e.. No fibrinolysis)

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

Thrombin Produced/Surges when?

A
  • Produced throughout CPB
  • Surge @ termination of bypass
  • Surge after protamine administration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Thrombin

A

-Amplifier protein
-Activates many cell lines
-Inflammation
-Coagulation
-Fibrinolysis
-Metabolically active in sites where
heparin cannot reach it

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

Plasminogen Activator Inhibitor 1 (PAI-1)

 - regulates?
 - released by?
A
  • Regulates TPA

- Released by Liver and Endothelial Cells

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

Plasminogen Activator Inhibitor 1 (PAI-1)

-binds to what?

A
  • PAI-1 binds to TPA as it’s exported from endothelial cells
    • Therefore, TPA must over comecirculating
    • Initiate fibrinolysis
    • Buffer to surges of TPA
    • Released in response to inflammatory mediators
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Plasminogen Activator Inhibitor 1 (PAI-1)

A
  • is Prothrombic
    -Overcomes and suppresses fibrinolytic effect
    of TPA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does PAI-1 overcomes and supresses finbrinolytic effect of TPA?

A

-Thrombin–makes clot
-TPA breaks up clot PAI-1 prevents TPA from breaking down clots
›Hemostasis!

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

TPA directly cleaves ?

A

plasminogen-> Plasmin

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

When TPA cleaves plasminogen to plasmin what happens? (3)

A
  • Exposes Lysine binding sites
  • Fibrinogen and fibrin bind @ these lysine binding sites
  • Proteolytic attack leads to breakdown products
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

TPA breaks apart what?

A
  • Breaks apart fibrin and therefore, the clot

- Leads to post-op bleeding

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

Fibrin

A

crosslinks platelets to make a clot

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

Antifibrinolytic Agents

A

Lysing Analogs
›Aminocaproic Acid (ACA) / Amicar
›Tranexamic Acid (TA)
Aprotinin

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

Antifibrinolytic Agents

Lysing Analogs

A

›Aminocaproic Acid (ACA) / Amicar ›Tranexamic Acid (TA)

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

Aminocaproic Acid (ACA) / Amicar

A

Antifibrinolytic Agents

  • 2 lysine molecules stuck together
  • Competitively binds to lysine sites of plasminogen/ plasmin
  • Prevents Plasmin from binding to fibrinogen/fibrin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Aprotinin is?

A

Antifibrinolytic Agent

  • 58 amino acid polypeptide
  • Single Lysine>High affinity for plasmin at this site
  • Non-specific serine protease inhibitor
  • Has other actions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Aprotinin catalyzes what?

A

Catalyzes multiple reactions of inflammation,

coagulation, and other cellular attack mechanisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

2 commercially available lysine analogs

A

ACA and TA

Clinically available for 40+ years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Lysine Analogs Pharmavology

A
  • IV Administration
  • Uptake is immediate
  • Small, water-soluble molecules
28
Q

Where are Lysine Analogs Distributed ?

A

Distributed readily into extravascular water spaced before being taken up into various cells and tissues.

29
Q

TA specific pharmacology?

A

Weak protein-bound

›Crosses BBB and Placenta

30
Q

Lysine Analogs excretion

A

Renal excretion

31
Q

Lysine Analogs T1/2

A

Half-life: 1-2 hours with IV administration

32
Q

ACA loading dosing

A

Loading Dose: 75-150mg/kg (5-10gm in adults)

33
Q

ACA IV infusion dose?

A

IV Infusion: 10-15mg/kg/hr

›Continues until end of CPB or until Protamine is given

34
Q

ACA Pump dose

A

Pump Dose: 2-2.5g/L
›Some add/ some don’t
›Makes sense to add b/c of added plasma volume on pump

35
Q

ACA Daily, et al Protocol (aka: “10-10-10”) dosing?

A

›10g given as slow bolus (5-10min) pre-CPB
›10g in CPB prime
›10g after CPB

36
Q

ACA dosing Pt with kidney disease

A

›Normal/reduced LD
›Reduced continuous infusion rate
ACA: 5mg/kg/hr
TA: 0.5mg/kg/hr

37
Q

ACA timing of initial dose

A

-As early as induction and incision
-Reports of clot formation on PA Catheter and EKG ST-segmen changes
›Await full anticoagulation with heparin prior to administration

38
Q

TA stand for?

A

Tranexamic Acid

39
Q

Tranexamic Acid what is it?

A

Antifibrinolytic agent

Lysing Analogs

40
Q

TA Loading Dose:

A

10-15mg/kg over 10-15min

41
Q

TA Infusion Dose:

A

1-1.5mg/kg/hr

42
Q

TA Pump Dose

A

2-2.5mg/L

43
Q

TA doses compared to ACA dose

A

1/7 to 1/10th of ACA

44
Q

what is DIC?

A

Disseminated intravascular coagulopathy/tion or less commonly as consumptive coagulopathy,
- pathological process characterized by the widespread activation of the clotting cascade that results in the formation of blood clots in the small blood vessels throughout the body. This leads to compromise of tissue blood flow and can ultimately lead to multiple organ damage.

45
Q

Lysing Analogs Side affects in DIC patients

A

Intravascular Clots

46
Q

Lysing Analogs Side affects in Thromboembolic Complications (5)

A 
›Reduced Graft Patency
›DVT
›PE
›Stroke
›MI
›**All theoretically possible after heparin
neutralization, but no association has been
found
47
Q

Patients at low risk for transfusion (despite
CPB) may not benefit from what type of drugs?

(something to consider)

A

— may not benefit from prophylactic anti-fibrinolytics. But may help tip the scales between transfusion or not if they are on the fence.

48
Q

Aprotinin - structure?

found where?

A
  • 58 amino acid polypeptide
  • Found in all mammalian lung tissue
  • Isolated from bovine lung
49
Q

Aprotinin activated site?

A

-contains single lysine
-Binding site for most serine proteases it
inhibits

50
Q

KIU

A

Kilo international units

51
Q

Aprotinin: Full Hammersmith Regimen (Most common) – pump/pt/infusion?

A

›2 million KIU in pump
›2 million KIU to pt over 30-60 minutes
›500,000 KIU/hr infusion for pump run

52
Q

Aprotinin T1/2

A

5 hours with this regimen

›Renal excretion

53
Q

Aprotinin Blood loss and transfusions required are lowest with what dosing?

A

with full dose regimen

54
Q

Aprotinin Allergic reactions caused by?

found in peds when?

A

-Foreign protein from bovine source
-Size similar to protamine
-1st time exposure reaction rare
-Found reaction in kids with less than 6
months between exposures
›FDA revised advisory to put 12 months between exposures

55
Q

Aprotinin how to test dose for an allergic reaction?

A

-Test dose of 1mL given prior to loading dose
-Wait about 10 min after test dose before
starting loading dose

56
Q

Aprotinin effects what substances? (8)

A 
Non-specific serine protease inhibitor
Effects:
›Trypsin
›Chymotrypsin
›Plasmin
›Kallikrein !!!! (Know this one)
›Bradykinin
›TPA
›Urokinase Plasminogen Activator
›Complement
57
Q

Kallikrein does what?

A 
>Decrease inflammation
>Doesn’t affect bleeding
›DOES activate intrinsic cascade
›Activation of coagulation precursor proteins
›Activates pro-inflammatory WBCs
›Inhibits Platelet-WBC Interactions
58
Q

Are TA and ACA FDA approved for prophylactic use in cardiac surgery?

A

NO

59
Q

Aprotinin - FDA Revised labeling (2006)

A

Don’t give w/in 12 mo of prior exposure
›Only for patients who are at increased risk for blood loss and blood transfusion associated
with CPB in the course of a CABG

60
Q

Recombinant Factor VIIa cost?

A

$5,000-$9,000 /dose

May require multiple doses

61
Q

Aprotinin competes with what in the Acending Loop of Henle?

A

COmpetes with creatinine in the
ascending Loop of Henle.
›Expect the rise in creatinine with Aprotinin
> this does not mean there is necessarily renal damage

62
Q

What is the cheapest? ACA, TA or Aprotinin?

A 
ACA < TA < Aprotinin 
--ACA–generic›$1.50-$10 per 5gm vial
        ›Case: $5-$30
--TA–generic›Case: $20-$300
--Aprotinin–off patent, but costly to extract›$300-$450 per bottle
      ›Case: $1000-$1500
63
Q

In 2008 what happened to Aprotinin ?

A

Permanently withdrawn from the
market
›Use is limited to very select research

64
Q

Retrospective studies associate Aprotinin with: (adverse side effects {4])

A
  • Renal Failure
  • Stroke
  • MI
  • Increased Mortality
  • *NOT seen with Lysine Analogs
65
Q

How to avoid post op bleeding - in general?

A

-Rewarm the patient thoroughly
-Reverse Protamine
-Get all the surgical bleeders
-Be aware of hemodilution
-Consider use of antifibrinolytic/ lysine
analog

Perf Tech II (exam 2) (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions