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Sp: Methods 1 > 11. Cardiac Surgery Concepts > Flashcards

11. Cardiac Surgery Concepts Flashcards

1
Q

CABG

A

coronary artery bypass

procedure where normal blood flow is restored to an area of the heart that has an obstructed coronary artery

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2
Q

3 steps for CABG

A

1- blood vessels are harvested
2- grafts are sewn proximal and distal to blockage
3- blood flows through graft and bypasses the blockage

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3
Q

what are the 3 vessels that can be harvested for CABG?

A 
radial artery (not common)
saphenous vein
left internal mammary artery (LIMA)
right internal mammary artery (RIMA)
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4
Q

where is proximal anastomosis

A

on the aorta

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5
Q

where is distal anastomosis

A

on the coronary artery distal to obstruction

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6
Q

In what case would you have 1 proximal anastomosis and 3 distal anastomosis’?

A

triple bypass using the LIMA

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7
Q

Which anastomosis’ usually get sewn on first?

A

the distals

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8
Q

What is the most commonly used graft?

A

left internal mammary artery LIMA

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9
Q

what is the LIMA usually anastomosed to?

A

LAD

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10
Q

Are arterial or venous grafts preferred for CABG?

A

arterial because they have to carry arterial blood

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11
Q

10 year rate of reocculsion for saphenous (%)

A

60% rate of reocculsion

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12
Q

10 year patency rate for LIMA (%)

A

90%

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13
Q

which is more patent the LIMA or radial artery?

A

LIMA

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14
Q

what is the most likely reason for the high patency of the LIMA?

A

it is a “live graft” meaning that the proximal origin from the subclavina is left intact

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15
Q

which is less invasive PCI or CABG?

A

PCI- percutaneous coronary intervention

balloon angioplasty or stenting (alternative to CABG)

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16
Q

better 5 year survival and patency? CABG or PCI?

A

CABG

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17
Q

lower risk of stroke at 5 years? CABG or PCI?

A

PCI

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18
Q

drug eluting stents

A

newer stents that slowly release a drug in order to slow the narrowing process

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19
Q

cardiopulmonary bypass machine

A

“heart lung machine”

functions as heart and lungs bc drains deox blood and oxygenates and removes CO2 then pumps back into body

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20
Q

purpose of CPB machine

A

keep the pt alive while the surgeon:
1. stop the heart
2. drain the blood

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21
Q

does the heart have to be arrested for cardiac surgery?

A

it is not mandatory but it is common and sometimes the surgeon will do it anyway

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22
Q

does the heart have to be arrested when the patient goes on cardiopulmonary bypass?

A

no, it is possible for the heart to remain beating while on bypass

however, it is most common to be arrested for bypass

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23
Q

how is the heart arrested?

A

surgeons inject cardioplegia into heart

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24
Q

how does cardioplegia stop the heart?

A

it alters transmembrane electrical potential in cardiac myocytes

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25
Q

what is in cardioplegia?

A

potassium

other additives:
glucose, magnesium, calcium, bicarb, buffers, and free radical scavengers (mannitol)
it can be mixed and injected with blood

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26
Q

when do you need to drain the blood from the heart?

A

any surgery where you have to open up the heart

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27
Q

6 parts of the CPB machine circuit

A

1- deox blood is drawn from heart through venous cannula
2- venous blood is stored in venous reservoir
3- blood sent through oxygenator/heat exchanger and arterial filter
4/5- blood reinfused into the body via “main pump” that pumps blood into aorta through “arterial cannula”
6- aortic cross clamp is usually placed on ascending aorta

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28
Q

what are the places that the venous cannula is placed?

A

right atrium (most common)
SVC
IVC
femoral vein

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29
Q

what does the venous reservoir do?

A

stores a surplus of blood and helps remove any air that inadvertently entered the bypass circuit

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30
Q

what happens when blood goes through the oxygenator, heat exhanger, and filter
(4)

A

fat globules and air particles are filtered out
temp is controlled
blood oxygenated
CO2 removed

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31
Q

what are the two reasons that an aorta crossclamp is placed?

A

1-prevent blood from backing up into the heart
2-prevent CP washout

2- keep heart arrested by keeping cardioplegia solution in heart

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32
Q

what are the 8 bypass machine components?

A 
venous cannula(s)
venous reservoir
main pump
oxygenator
heat exchanger
arterial filter
arterial cannula
ultrafilter
cell salvage suction
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33
Q

most common method for removing deoxygenated blood from the pt during bypass

A

venous cannula in RA

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34
Q

when can you not use a venous cannula in the RA?

A

when you have right sided heart operation

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35
Q

what is the most common venous cannulas to use for open right sided heart surgeries?

A

SVC and IVC cannulas

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36
Q

what cannula can you place without having to open the chest?

A

femoral cannula (venous and arterial)

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37
Q

when is the femoral and arterial cannulation for CPB particularly useful?

A

when bypass must be initiated emergently

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38
Q

what are the two primary purposes of the venous reservoir?

A

1-remove air that enters the venous drainage line

2- stores a surplus of blood in the bypass circuit

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39
Q

does the traditional venous reservoir remove all air in the venous blood?

A

no

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40
Q

what does the reservoir act as a buffer for?

A

imbalances between venous return and arterial flow when the heart and lungs are exsanguinated

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41
Q

how much blood may the venous reservoir need to hold?

A

1-3L

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42
Q

main pump

A

pumps blood to the body via arterial cannula and it has the option of pulsatile flow or non pulsatile flow

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43
Q

non pulsatile flow

A

more common since 2016

centrifuge pump

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44
Q

pulsatile flow

A 
new technique (less common since 2016)
roller or diagonal pumps
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45
Q

advantage of pulsatile flow

A

perfusion is better because it is more physiologic and stimulates the endothelium

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46
Q

disadvantage of pulsatile flow

A

achieving pulsatile flow from CPB machine is difficult

you could damage the blood elements

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47
Q

heat exchanger

A

cools and heats blood

allows perfusionist to control the temp of pt

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48
Q

what can form when blood is heated?

A

air bubbles bc gas solubility decreases as temp increases

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49
Q

what type of temp control is implemented during CPB

A

modest hypothermia ~34 degrees C for organ protection

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50
Q

advantages to modest hypothermia (2)

A

decreases oxygen requirements

decreases anesthetic requirements (hypothermia acts as anesthetic)

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51
Q

decreasing body temp by 1 degree decreases cerebral oxygen consumption by how much

A

5%

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52
Q

decreasing body temp by 10 degree decreases cerebral oxygen consumption by how much

A

50%

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53
Q

disadvantages of hypothermia (2)

A

more likely coagulopathy (more bleeding)

increased blood viscosity (decrease perfusion)

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54
Q

3 things oxygenator does

A

oxygenates blood
removes co2
site for volatile agent entry into bypass machine (perfusionist controls volatile agent)

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55
Q

2 types of oxygenators

A

bubble oxygenator

membrane oxygenator

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56
Q

bubble oxygenator

A

simple and low cost
more trauma to blood
RARELY USED

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57
Q

membrane oxygenator

A

increased complex and cost
less blood trauma
USED MORE COMMON

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58
Q

problems (6) with oxygenator

A

damages blood
inflammatory respinse
organ dysfunction
decr WBC
decr platelets
incr PAP

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59
Q

arterial filter

A

removes fat globules and air bubbles from circuit

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60
Q

what causes the spontaneous formation of microbubbles in the extracorpreal circuit?

A

excessive negative pressure in particular in the venous part of circuit

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61
Q

ultrafilter

A

hemoconcentrator that is sometimes added

removes excess water and electrolytes when low Hct

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62
Q

what are the two types of suction used during CPB?

A

standard suction

blood salvage suction

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63
Q

what are the three types of blood salvage suction

A

cardiotomy suction
cell saver suction
left ventricular vent

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64
Q

blood salvage suction definition

A

blood that will eventually return to pt
decreases chance of pt needing donor transfusion

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65
Q

cardiotomy suction

A

aspirated blood from chambers and surgical field
prevents distension and air embolism
returned to extracorporeal circuit via cardiotomy reservoir

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66
Q

Is cardiotomy used before or after the patient is heparinized?

A

after

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67
Q

can cardiotomy suction be used when the patient is off the bypass machine?

A

No

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68
Q

cardiotomy suction advantage

A

it is whole blood

includes: clotting factors, platelets and PRBC

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69
Q

cardiotomy suction disadvantage (3)

A

1- blood is damaged by the bypass machine
2- Hct is lower
3- contributes to hemolysis and particulate emboli

2-contributes to hemolysis and particulate emboli during CPB

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70
Q

what type of suction is associated with a more pronounced systemic inflammatory response?

A

cardiotomy

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71
Q

How does the cardiotomy suction cause hemolysis, GME, fat globule formation, activation of coagulation and fibrinolysis, cellular aggregation and platelet injury or loss?

A

amount of room air that is aspirated with blood causes turbulence and high sheer stress that causes damage

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72
Q

cell saver suction definition (2)

A

1- blood suctioned from field, washed and centrifuged

2- RBCs moved to infusion bag and transfused back into patient

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73
Q

what is the Hct of cell saver blood?

A

50-70%

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74
Q

cell saver advantages 3

A

1- particles (fat, air, tissue) are filtered out
2- Hct is higher
3- blood is less damaged

2- blood is less damaged bc it does not go through bypass machine

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75
Q

cell saver disadvantages 2

A

1 it is not whole blood (mostly PRBC)

2 takes longer before it can be reinfused

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76
Q

can you use cardiotomy and cell saver?

A

yes this is a good option to use both, choose one depending on the type of fluid

cardiotomy is during bypass
cell saver is off-bypass

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77
Q

left ventricle vent placement

A

inserted into the left ventricle through the pulmonary vein

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78
Q

what blood does the LV vent remove?

A

venous blood not picked up by venous reservoir (bronchial and thebesian veins)

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79
Q

purpose of LV vent

A

prevent left ventricular distension

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80
Q

risk of LV suction

A

air embolism causing a stroke

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81
Q

what is the most likely time to get an air embolism with LV vent? prevention?

A

insertion or removal of the vent, or excessive suction

prevention by letting heart fill before insertion and flooding the field with fluid during removal

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82
Q

what does excessive suction lead to?

A

air introduction drawn from purse string sutures in left atrium or aorta

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83
Q

what is the most common way of arresting the heart?

A

antegrade cardioplegia (CP)

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84
Q

antegrade cardioplegia definition

A

arresting the heart by injecting cardioplegia into the coronary arteries through the coronary ostia (os)

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85
Q

coronary ostia (os)

A

the openings from the aorta to the coronary arteries

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86
Q

what is the most common way to do antegrade cardioplegia?

A

CP is injected into the aortic root via cardioplegia cannula
cross clamp is needed to keep CP from washing out into the body

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87
Q

what is the less common way to do antegrade CP?

A

direct cannulation of the coronary os and CP is injected through those

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88
Q

how do we perfuse the heart during CPB?

A

the CP line can also infuse blood into the coronary arteries so the heart is perfused

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89
Q

what are the the two reasons that you would need to perfuse the heart via the CP line?

A

ascending aortic clamp is placed

heart needs to be arrested

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90
Q

retrograde CP definition

A

CP being injected retrograde through the coronary sinus

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91
Q

what is the main risk with retrograde CP?

A

coronary sinus is more likely to rupture during CP injection because its a vein, surgeon will measure pressure during injection

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92
Q

steps to monitoring pressure with retrograde cardioplegia (3)

A

1- surgeon throws sterile non compliant tubing over drape (attached to CP line)
2- anesthetist hooks tubing to either CVP or PAP stopcock on triple transducer
3- during phase when heart is arrested the stopcock will be off to the pt and open to the retrograde line

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93
Q

Stopcock on transducer is turning to the side; what are you measuring?

A

CVP or PAP

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94
Q

stopcock on transducer is turned up; what are you measuring?

A

retrograde cardioplegia (if attached)

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95
Q

what are the two indications for retrograde CP?

A

1- helps arrest areas of heart distal to high grade obstruction
2- helps arrest heart when antegrade CP would wash out easily

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96
Q

what situations would antegrade CP wash out easily?

A

ascending aorta repair
open aortic valve repaire

open aortic valve repair

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97
Q

where does the aortic cross clamp need to be placed in reference to the arterial cannula

A

proximal to the arterial cannula on the ascending aorta

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98
Q

where must the aortic cross clamp be placed

A

ascending aorta to allow for total body perfusion

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99
Q

what would happen if you placed the aortic cross clamp while the heart was beating and full of blood?

A

heart attack or aortic rupture and death

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100
Q

sequence for arresting the heart and going on bypass (3)

A
  1. Bypass and drain blood from heart via venous cannula
  2. place aortic cross clamp
  3. arrest heart with CP solution
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101
Q

When can you place an aortic cross clamp on a beating heart?

A

when the heart has been drained of blood

this will happen when going on and coming off pump

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102
Q

what two ways can the heart be arrested without using an aortic cross clamp?

A

retrograde CP

directly cannulating the coronary os for CP

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103
Q

advantages of aortic cross clamp 3

A

1 easier to arrest heart
2 prevents air from entering circulation and going to the braine
3 prevents reinfused blood from backing up into heart

104
Q

disadvantage to aortic cross clamp 2

A

1physiologic perfusion to the heart is not possible
is perfused through CP cannula
2 increases risk of stroke from possible dislodging of emboli

105
Q

partial aortic cross clamp

A

used when graft is sewn in and hole must be made

also associated with emboli and stroke

106
Q

when are the two times that CPB is necessary

A

heart needs to be empty
- open valve repair
- open aorta repair
heart is going to be arrested

heart is going to be arrested

107
Q

what are the two advantages to bypass

A

easier for surgeon
more hemodynamically stable

more hemodynamic stability

108
Q

what are the 8
disadvantages of CPB

A 
1 - hemodilution (decr Hct)
2 - aortic cross clamp risk for embolism
3 - blood damage
4 - large volume shift
5 - postperfusion syndrome
6 - less effective tissue perfusion
7 - difficulty coming off pump
8 - pulmonary complications more likely
109
Q

how much fluid is the bypass machine primed with?

A

2,000mL

110
Q

what % of the pts circulating blood volume is the hemodilutional bolus equal to

A

30-50%

111
Q

what are the contents of the priming fluid

A 
heparin
bicarb
mannitol
colloid
possible steroids or antifibrinolytics (amicar)
112
Q

priming volume of bypass for adults

A

2L

113
Q

when would the machine be primed with blood?

A

pediatrics -> to prevent over dilution of blood

114
Q

what are the two pulmonary complications that could be seen with bypass

A

pulmonary edema more likely from activation of complement

reduces the effectiveness of natural surfactant

115
Q

what are the two organs that have decreased perfusion on bypass and why does it matter

A

renal
hepatic

drugs arent cleared well

116
Q

3 causes of blood damage on bypass

A

hemolysis
platelet conc is reduced and clotting decr clotting factor function
intense inflammatory response

117
Q

what can the intense inflammatory response cause?

A

disturbances in vascular tone, permeability, fluid shifts and organ dysfunction
heart function compromised when coming off pump

118
Q

what can a large volume shift cause?

A

transient cerebral edema

119
Q

off pump heart surgery

A

suction clamps applied
good bc no negative effects from bypass machine
bad bc clamps may cause significant hypotension and/or arrhythmias

120
Q

off pump pros

A

no negative effects from bypass machine

121
Q

off pump cons

A

clamps cause:
- significant hypotension
- arrythmias

122
Q

partial CPB

A

only drains part of venous blood and goes through the bypass machine and some blood goes through the pulmonary circulation

123
Q

if a surgeon attempts an off pump and the pt cant tolerate it what are the two options?

A

full bypass: heart arrested and heart perfusion non physiologic

partial bypass: heart beating and heart perfusion physiologic

124
Q

3 implications of partial CPB

A
  1. heart must stay beating
  2. pt needs to be oxygenated/ventilated/volatile agent delivered
  3. aortic clamp doesnt need to be placed
125
Q

benefits of partial CPB

A
  1. pulsatile flow
    (physiologic perfusion)
  2. decr risk of stroke (no cross clamp)
126
Q

LH partial

A

half the blood is taken out

127
Q

left heart partial bypass 6

A

1-blood travels through right heart and pulm
2-some blood removed from LA with venous cannula to bypass machine to perfuse lower extremities via arterial cannula
3-some blood stays in left atrium and goes out the aorta to perfuse the head
4- only left heart bypassed
5- blood already oxygenated
6- heart must stay beating and lungs must be ventilated

128
Q

implications of LH partial bypass

A

only LH is bypassed
lungs must be ventilated w/VA
heart must stay beating
no oxygenator required

129
Q

do you need oxygenator for LH partial bypass

A

no

130
Q

LH partial bypass requires

A

ventilator on
volatile agent on

131
Q

left heart bypass circuit parts

A

tubing

centrifugal pump

132
Q

indication of left heart partial bypass

A

open descending thoracic aortic aneurysm repair

133
Q

LH Partial Bypass implications

A

only left hear is bypasses
lungs must be ventilated w/VA
heart must stay beating
bypass machine does not need oxygenator

134
Q

what perfuses the head during partial left heart bypass

A

the heart

135
Q

what perfuses the lower body during partial left heart bypass

A

arterial cannula

136
Q

left/right heart bypass advantages 5

A

1 heart stays beating (physiological perfusion remains)
2 lower circuit prime volume
3 lower chance of postop renal failure
4 blood pressure is controlled by perfusionist
5 no air blood contact = less blood damage

137
Q

what does lower circuit prime volume lead to? 3

A

less hemodilution
less blood damage
less heparinization needed

138
Q

what is the target ACT for partial CPB?

A

150-200 seconds

139
Q

what are the % chance of renal failure for left heart bypass, simple cross clamp, and CPB?

A

left- 4%
simple- 9%
CPB- 11%

140
Q

left/right heart bypass disadvantages

A

cant add blood or fluids
cant warm/cool pt
air embolization may be more likely

141
Q

right heart bypass 4

A

1- venous cannula in SVC and IVC remove blood and sent to machine
2- reinfused blood though arterial cannula in pulm artery, cross clamp on pulm artery
3- blood goes to lungs thus we need to ventilate and oxygenate
4- heart stays beating and lungs are ventilated

142
Q

why is there a lower stroke risk with right heart bypass

A

no aortic cross clamp is needed
(cross clamp placed on pulmonary artery)

143
Q

3 indications for right heart partial bypass

A

tricuspid valve repair
pulmonic valve repair
right ventricle assist device (RVAD) placement

144
Q

when on right heart partial bypass the surgeon can complete surgery without: (3)

A

arresting heart
clamping aorta
using oxygenator

145
Q

where do they place the cross clamps for ascending or aortic arch aneurysms?

A

proximal and distal to aneurysm

146
Q

what are the options to protect the brain when total body perfusion isnt feasible with arterial cannula due to clamp location (3)
can you use these together?

A

deep hypothermic circulatory arrest (DHCA)
circ arrest w/antegrade and/or retrograde
antegrade w/normothermia

147
Q

deep hypothermic circulatory arrest

A

perfusionist makes pt so cold that oxygen demands are so low they can survive a short amount of time without perfusion

148
Q

indications for DHCA

A

ascending aorta repair
aortic arch repair
descending aorta repair
clipping certain complex brain aneurysms

149
Q

how does the circ arrest process work?

A

1- pt put on bypass
2- heat exchanger decreases temp
3- heart is arrested and circulation is slowed to near stand still
4- decrease in oxygen consumption allows for the pt to have minimal blood flow

150
Q

during circ arrest where is the arterial cannula placed?

A

femoral artery
innominate artery
axillary artery

151
Q

what is the target temp before starting circ arrest?

A

15 to 17 degrees C

longer the operation they may need to be colder

152
Q

what monitors are used to monitor the depth of hypothermia and ensure electrial silence during DHCA

A

BIS and EEG

153
Q

when is the EEG usually isoelectric?

A

between 15-20 degrees C (nasopharyngeal temp)

154
Q

how much longer is the patient cooled after they are isoelectric?

A

10 minutes to ensure homogenous cooling of brain

155
Q

how long is circ arrest safe? chart

A

temp – mins
20C- 30-40mins
16C- 45-60mins

156
Q

circ arrest should not be performed for longer than?

A

60 min

157
Q

time limit for most have no neurologic complications

A

<30 min

158
Q

time limit for increased incidence of brain injury

A

> 40 min

159
Q

time limit for most suffer from irreversible brain damage

A

> 60min

160
Q

who can tolerate longer periods of circ arrest?

A

neonates and children

161
Q

complications of DHCA 3

A

complications of hypothermia
- DIC (coagulopathy)
- incr bleeding
neurologic complications
potential neurologic complications from cooling or rewarming pt too rapidly

162
Q

what can rapid cooling cause

A

lower neurodevelopmental outcome scores

lower neurodevelopmental outcome scores

163
Q

rapid cooling

A

<20 min to deep hypothermia

164
Q

what can rapid rewarming cause 4

A

organ damge
deleterious to neurologic outcome
promotes gas bubble formation (solubility decrease and temp increase)
cerebral desaturation and uneven warming

165
Q

what is the rewarming rate not to exceed?

A

1C core temp per 3 min of bypass time

166
Q

when should rewarming stop?

A

nasopharyngeal temp reaches 35C

167
Q

DHCA anesthetic management 2

A

1- must use nasal temp probe (reflection of brain temp)
2- additional brain protection
- periop steroids
-hyperoxygenation before
- 20 min of cooling for adequate cerebral protection
- pack head in ice
-intermittent cerebral perfusion in 15-20 min periods

168
Q

what are the two temp probes to have for circ arrest?

A

nasal (brain)

bladder (core)

169
Q

why use nasal temp probe during circ arrest

A

accurate reflection of brain temperature

170
Q

additional brain protection during DHCA

A

steroids
hyperoxygenation
packing head with ice
intermit cerebral perfusion between 15-20 min periods

171
Q

retrograde cerebral perfusion during cxirc arrest

A

cold blood perfused to head via extra cannula in SVC

172
Q

normothermic antegrade cerebral perfusion

A

extra perfusion line is placed in right axillary artery to perfuse head
USED WITHOUT CIRC ARREST

173
Q

where is the extra perfusion line placed in antegrade cerebral perfusion?

A

proximal to cross clamp

174
Q

antegrade cerebral perfusion

A

used with normothermia or circ arrest

disadvantage: may increase incidence of stroke

175
Q

normothermic antegrade cerebral perfusion: head

A

extra perfusion line
(R axillary)

176
Q

normothermic antegrade cerebral perfusion: lower extremity

A

arterial cannula

177
Q

antegrade cerebreal perfusion CON

A

incr incidence of stroke

178
Q

circ arrest is ______ perfusion

A

partial perfusion

179
Q

antegrade normothermia is ______ perfusion

A

complete perfusion

180
Q

PT

A

prothrombin time

Extrinsic pathway

181
Q

normal PT

A

12-15 seconds

182
Q

PTT

A

partial thromboplastin time

intrinsic pathway

183
Q

normal PTT

A

25-40 sec

184
Q

INR

A

international normalized ratio
standardized PT result

185
Q

INR normal range

A

0.9-1.1

186
Q

INR value that an epidural or catheter placement/removal is unsafe

A

INR > 1.4

187
Q

how do pts survive aortic cross clamping?

A

pt is placed on the bypass and heart emptied prior to placing the clamp

188
Q

order of cross clamping

A

bypass
cross clamp
CP solution

189
Q

unfractionated heparin mechanism

A

enhances antithrombin III 1000x

190
Q

unfractionated heparin pathway

A

Intrinsic
PTT

191
Q

heparin reversal

A

protamine

192
Q

how should heparin be given during cardiac surgery

A

via central line

193
Q

hepain dose for bypass

A

300-400 units/kg prior to aortic cannulation

194
Q

ACT

A

clotting time test used to assess coag
done when heparin is given

195
Q

normal ACT

A

100-150 s

196
Q

goal ACT prior to going on pump

A

> 450 s

197
Q

HIT mechanism

A

pt immune system develops antibodies against heparin

198
Q

HIT symptoms

A

thrombocytopenia
thrombosis

199
Q

HIT is most often caused by

A

standard heparin
(sometimes fractionated heparin)

200
Q

alternat to heparin for cardiac surgery

A

Argatroban
(direct thrombin inhibitor)

201
Q

argatroban reversal

A

none

202
Q

significance of Antithrombin III deficiency

A

heparin will not work

203
Q

causes of antithrombin III deficiency

A

genetic
acquired from previous heparin admin

204
Q

management for antithrombin III deficiency

A
  1. give antithrombin III
  2. give FFP
205
Q

LMW heparin delivery

A

subQ

206
Q

unfractionated heparin delivery

A

IV

207
Q

LMW heparin duration

A

12-24 hrs (longer)

208
Q

standard heparin duration

A

1 hr half life

209
Q

most common type of fractioned heparine

A

lovenox (enoxaparin)

210
Q

LMW heparin PTT impact

A

does not prolong as much

211
Q

LMW heparin alternative to PTT

A

anti-Xa assay

212
Q

which is reversed more easily: LMW or standard heparin

A

standard heparin is more easily reversed with protamine

213
Q

vitamin K antagonist

A

coumadin (warfarin)

214
Q

coumadin pathway

A

Extrinsic

215
Q

coumadin delivery

A

PO

216
Q

coumadin coag tests impacted

A

PT
INR

217
Q

which factor does coumadin impact most

A

factor VII

218
Q

how long should coumadin be withheld before elective surgery

A

5 day

219
Q

management of coumadin for emergent surgeries?

A

reverse coumadin:
FFP
vit K

220
Q

antiplatelet drugs

A

aspirin
plavix (clopidogrel)

221
Q

plavix drug categroy

A

P2Y12 inhibitor

222
Q

can plavix be reveresed

A

no
(plts might help)

223
Q

delay elective surgery for ____ days after taking plavix

A

5-7 days

224
Q

discontinue aspirin ____ days before elective surgery

A

7 days

225
Q

dual antiplatelet therapy is typically used in which pts

A

pts with recent coronary baloon angioplasty and/or
stent

226
Q

dual antiplatelet therapy drugs

A

plavix + aspirin

227
Q

balloon angioplasty wait time for elective surgery

A

14 days
(continual DAT)

228
Q

bare metal stent wait time for elective surgery

A

1 month
(continue DAT)

229
Q

drug eleuting stent wait time for elective surgery

A

6 months
(continue DAT)

230
Q

when can you consider elective surgery at 3 months after drug eluting stent (DAT)

A

risk for delay > risk for ischemia

231
Q

DAT and urgent surgery

A

typically continue aspirin
balance risk of plavix based on thrombotic/hemorrhagic risk

232
Q

what should pts take after DAT is discontinued

A

lifelong aspirin therapy

233
Q

when should pts discontinue aspiring

A

low embolic
high hemorrhagic risk

spine
neuro
eye

234
Q

direct factor Xa inhibitors

A

xarelto (rivaroxiban)
eliquis (apixaban)

235
Q

xarelto delivery

A

oral

236
Q

xarelto reversal

A

andexxa

237
Q

xarelto discontinue before surgery

A

24 hrs

238
Q

eliquis reversak

A

andexxa

239
Q

eliquis discontinue prior to surgery

A

48 hrs

240
Q

thrombolytics

A

rTPA
streptokinase
urokinase

241
Q

thrombolytics discontinue before surgery

A

10 days

242
Q

direct thrombin injibitors

A

argatroban

243
Q

what can be used for anticoag in pts that cannot receive heparin due to HIT

A

direct thrombin inibitors
(argatroban)

244
Q

when is protamine dosed in cardiac surgery

A

after pt is off bypass

245
Q

protamine dose

A

1mg per 100 units heparin

246
Q

prtamine should be given

A

peripherally
slowly (over 10 mins)

247
Q

protamine mechanism

A

binds heparin
heparin cannot bind antithrombin iii

248
Q

protamine side effects

A

hypotension
anaphylaxis
pulmonary vasoconstriction

249
Q

anaphylaxis reactions to protamine are more common in

A

rapid/central admin
prior protamine delivery
fish allergies
male pts w/vasectomy
diabetics

250
Q

warfarin reversal

A

FFP
vit K

251
Q

what is an alternate to FFP

A

PCC

252
Q

PCC

A

vit K dependent clotting factors

253
Q

PCC can reverse

A

warfarin (coumadin)

254
Q

vit K dep clotting factors

A

II
VII
IX
X

255
Q

PCC advantages

A

2x fast as FFP
1 dose every 24 hrs (less volume)
less adverse effects
faster prep time

256
Q

PCC disadvantages

A

20x more expensive
shorter acting
requires vit K co-admin

Sp: Methods 1 (15 decks)

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