Cardiac Surgery Concepts Flashcards

(230 cards)

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)
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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 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

some cardiac surgeries require the heart to stop or drain blood from heart
the CPB machine allows the pt to stay alive

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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

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23
Q

how is the heart arrested?

A

surgeons inject cardioplegia into heart

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24
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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25
when do you need to drain the blood from the heart?
any surgery where you have to open up the heart
26
6 parts of the CPB machine circuit
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
27
what are the places that the venous cannula is placed?
right atrium (most common) SVC IVC femoral vein
28
what does the venous reservoir do?
stores a surplus of blood and helps remove any air that inadvertently entered the bypass circuit
29
what happens during step 3 of the CPB machine (4)
fat globules and air particles are filtered out temp is controlled blood oxygenated CO2 removed
30
what are the two reasons that an aorta crossclamp is placed?
1-prevent blood from backing up into the heart | 2- keep heart arrested by keeping cardioplegia solution in heart
31
what are the 8 bypass machine components?
``` venous cannula(s) venous reservoir main pump oxygenator heat exchanger arterial filter arterial cannula ultrafilter cell salvage suction ```
32
when can you not use a venous cannula in the RA?
when you have right sided heart operation
33
what is the most common venous cannulas to use for open right sided heart surgeries?
SVC and IVC cannulas
34
what cannula can you place without having to open the chest?
femoral cannula (venous and arterial)
35
when is the femoral and arterial cannulation for CPB particularly useful?
when bypass must be initiated emergently
36
what are the two primary purposes of the venous reservoir?
1-remove air that enters the venous drainage line | 2- stores a surplus of blood in the bypass circuit
37
does the traditional venous reservoir remove all air in the venous blood?
no
38
what does the reservoir act as a buffer for?
imbalances between venous return and arterial flow, when the heart and lungs are exsanguinated the reservoir may need to hold as much as 1-3 L
39
main pump
pumps blood to the body via arterial cannula and it has the option of pulsatile flow or non pulsatile flow
40
non pulsatile flow
more common since 2016 | centrifuge pump
41
pulsatile flow
``` new technique (less common since 2016) roller or diagonal pumps ```
42
advantage of pulsatile flow
perfusion is better because it is more physiologic and stimulates the endothelium
43
disadvantage of pulsatile flow
achieving pulsatile flow from CPB machine is difficult | you could damage the blood elements
44
heat exchanger
cools and heats blood | allows perfusionist to control the temp of pt
45
what can form when blood is heated?
air bubbles bc gas solubility decreases as temp increases
46
what type of temp control is implemented during CPB
modest hypothermia ~34 degrees C for organ protection
47
advantages to modest hypothermia (2)
decreases oxygen requirements | decreases anesthetic requirements (hypothermia acts as anesthetic)
48
decreasing body temp by 1 degree decreases cerebral oxygen consumption by how much
5%
49
decreasing body temp by 10 degree decreases cerebral oxygen consumption by how much
50%
50
disadvantages of hypothermia (2)
more likely coagulopathy (more bleeding) | increased blood viscosity (decrease perfusion)
51
3 things oxygenator does
oxygenates blood removes co2 site for volatile agent entry into bypass machine (perfusionist controls volatile agent)
52
2 types of oxygenators
bubble oxygenator | membrane oxygenator
53
bubble oxygenator
simple and low cost more trauma to blood RARELY USED
54
membrane oxygenator
increased complex and cost less blood trauma USED MORE COMMON
55
what is the main problem with oxygenator
damages blood inflammatory respinse/organ dysfunction decrease white blood cells and platelets and increased PAP
56
arterial filter
removes fat globules and air bubbles from circuit
57
what causes the spontaneous formation of microbubbles in the extracorpreal circuit?
excessive negative pressure in particular in the venous part of circuit
58
ultrafilter
hemoconcentrator that is sometimes added | removes excess water and electrolytes when low Hct
59
what are the two types of suction used during CPB?
standard suction | blood salvage suction
60
what are the three types of blood salvage suction
cardiotomy suction cell saver suction left ventricular vent
61
blood salvage suction definition
blood that will eventually return to pt, decreases chance of pt needing donor transfusion
62
cardiotomy suction
aspirated blood from chambers and surgical field prevents distension and air embolism returned to extracorporeal circuit via cardiotomy reservoir
63
where does the blood go after it is in the cardiotomy reservoir?
venous reservoir
64
Is cardiotomy used before or after the patient is heparinized?
after
65
can cardiotomy suction be used when the patient is off the bypass machine?
No
66
cardiotomy suction advantage
it is whole blood | includes: clotting factors, platelets and PRBC
67
cardiotomy suction disadvantage (2)
1- blood is damaged by the bypass machine | 2-contributes to hemolysis and particulate emboli during CPB
68
what type of suction is associated with a more pronounced systemic inflammatory response?
cardiotomy
69
How does the cardiotomy suction cause hemolysis, GME, fat globule formation, activation of coagulation and fibrinolysis, cellular aggregation and platelet injury or loss?
amount of room air that is aspirated with blood causes turbulence and high sheer stress that causes damage
70
cell saver suction definition (2)
1- blood suctioned from field, washed and centrifuged | 2- RBCs moved to infusion bag and transfused back into patient
71
what is the Hct of cell saver blood?
50-70%
72
cell saver advantages 2
1- particles (fat, air, tissue) are filtered out | 2- blood is less damaged bc it does not go through bypass machine
73
cell saver disadvantages 2
1 it is not whole blood (mostly PRBC) | 2 takes longer before it can be reinfused
74
can you use cardiotomy and cell saver?
yes this is a good option to use both, choose one depending on the type of fluid
75
left ventricle vent placement
inserted into the left ventricle through the pulmonary vein
76
what blood does the LV vent remove?
venous blood not picked up by venous reservoir (bronchial and thebesian veins)
77
purpose of LV vent
prevent left ventricular distension
78
what is the most likely time to get an air embolism with LV vent? prevention?
insertion or removal of the vent, or excessive suction | prevention by letting heart fill before insertion and flooding the field with fluid during removal
79
what does excessive suction lead to?
air introduction drawn from purse string sutures in left atrium or aorta
80
what is the most common way of arresting the heart?
antegrade cardioplegia (CP)
81
antegrade cardioplegia definition
arresting the heart by injecting cardioplegia into the coronary arteries through the coronary ostia (os)
82
coronary ostia (os)
the openings from the aorta to the coronary arteries
83
what is the most common way to do antegrade cardioplegia?
CP is injected into the aortic root via cardioplegia cannula **cross clamp is needed to keep CP from washing out into the body**
84
what is the less common way to do antegrade CP?
direct cannulation of the coronary os and CP is injected through those
85
how do we perfuse the heart during CPB?
the CP line can also infuse blood into the coronary arteries so the heart is perfused
86
what are the the two reasons that you would need to perfuse the heart via the CP line?
ascending aortic clamp is placed | heart needs to be arrested
87
retrograde CP definition
CP being injected retrograde through the coronary sinus
88
what is the main risk with retrograde CP?
coronary sinus is more likely to rupture during CP injection because its a vein, surgeon will measure pressure during injection
89
steps to monitoring pressure with retrograde cardioplegia (3)
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
90
Stopcock on transducer is turning to the side; what are you measuring?
CVP or PAP
91
stopcock on transducer is turned up; what are you measuring?
retrograde cardioplegia (if attached)
92
what are the two indications for retrograde CP?
1- helps arrest areas of heart distal to high grade obstruction 2- helps arrest heart when antegrade CP would wash out easily
93
what situations would antegrade CP wash out easily?
ascending aorta repair | open aortic valve repair
94
where does the aortic cross clamp need to be placed in reference to the arterial cannula
proximal to the arterial cannula on the ascending aorta
95
what would happen if you placed the aortic cross clamp while the heart was beating and full of blood?
heart attack or aortic rupture and death
96
sequence for arresting the heart and going on bypass (3)
drain blood from heart via venous cannula place aortic cross clamp then arrest heart with CP solution
97
When can you place an aortic cross clamp on a beating heart?
when the heart has been drained of blood | this will happen when going on and coming off pump
98
what two ways can the heart be arrested without using an aortic cross clamp?
retrograde CP | directly cannulating the coronary os for CP
99
advantages of aortic cross clamp 3
1 easier to arrest heart 2 prevents air from entering circulation 3 prevents reinfused blood from backing up into heart
100
disadvantage to aortic cross clamp 2
1physiologic perfusion to the heart is not possible is perfused through CP cannula 2 increases risk of stroke from possible dislodging of emboli
101
partial aortic cross clamp
used when graft is sewn in and hole must be made | also associated with emboli and stroke
102
when are the two times that CPB is necessary
heart needs to be empty | heart is going to be arrested
103
what are the two advantages to bypass
easier for surgeon | more hemodynamic stability
104
what are the 7 disadvantages of CPB
``` 1-priming fluid causes hemodilution (Hct decrease) 2- aortic clamp usually placed 3- difficulty coming off pump 4- pulm complications more likely 5- perfusion less effective 6- pt blood is damaged 7- large volume shifts may occur` ```
105
how much fluid is the bypass machine primed with?
2,000mL
106
what % of the pts circulating blood volume is the hemofilutional bolus equal to
30-50%
107
what are the contents of the priming fluid
``` heparin bicarb mannitol colloid possible steroids or antifibrinolytics ```
108
when would the machine be primed with blood?
pediatrics, to prevent over dilution of blood
109
what are the two pulmonary complications that could be seen with bypass
pulmonary edema more likely from activation of complement | reduces the effectiveness of natural surfactant
110
what are the two organs that have decreased perfusion on bypass and why does it matter
renal, hepatic | drugs arent cleared well
111
3 causes of blood damage on bypass
hemolysis platelet conc is reduced and clotting factor function decrease intense inflammatory response
112
what can the intense inflammatory response cause?
disturbances in vascular tone, permeability, fluid shifts and organ dysfunction heart function compromised when coming off pump
113
what can a large volume shift cause?
transient cerebral edema
114
what is the part of the machine that determines whether it is an open or closed bypass system
the type of venous reservoir
115
is an open or closed bypass system more common?
open bypass system
116
open bypass system definition
venous drainage flows by gravity into venous reservoir thats open to atmosphere air naturally vented but in direct contact with air (bad) hardshell reservoir
117
closed bypass system definition
venous reservoir removed from system or is closed to atmosphere collapsible bag
118
benefits to using the open bypass system
automatically eliminates air (less risk of air embolism) volume delineation is clear actively purging air from closed system is distracting
119
advantages of closed bypass system 3
limited contact with air (limits injurt to elements of blood) decreased inflammatory response and fewer hematological disruptions some have smaller priming volumes
120
disadvantages of closed bypass 3
``` less precise visual monitoring of venous return air is not automatically purged (requires additional systems) less filters (more microemboli exiting) ```
121
what parts does a mini CPB circuit have
pump oxygenator reduced tubing length (reduction of priming volume) arterial filter (usually)
122
what parts does a mini CPB circuit NOT have
venous reservoir cardiotomy suction heat exchanger
123
what is the priming volume reduced to in a mini cardiopulmonary bypass circuit?
600mL
124
Is the mini CPB circuit open or closed?
closed (limits air contact)
125
advantages of mini CPB circuit 4
advantages of closed system improves myocardial protection (less problems restoring SR and less afib) associated with less blood transfusion associated with earlier recovery times and reduced ICU and hosp time
126
why is mini CPB circuit associated with less blood transfusion
lower priming volume | less hemodilution
127
disadvantages of mini cardiopulmonary bypass
demanding for perfusionist (must pay more attention to air handling) some studies say it isnt beneficial
128
off pump heart surgery
suction clamps applied good bc no negative effects from bypass machine bad bc clamps may cause significant hypotension and/or arrhythmias
129
partial CPB
only drains part of venous blood and goes through the bypass machine and some blood goes through the pulmonary circulation
130
if a surgeon attempts an off pump and the pt cant tolerate it what are the two options?
full bypass: heart arrested and heart perfusion non physiologic partial bypass: heart beating and heart perfusion physiologic
131
3 implications of partial CPB
heart must stay beating pt needs to be oxygenated/ventilated/ volatile agent delivered aortic clamp doesnt need to be placed
132
left heart partial bypass 6
1-blood travels through right heart and pulm 2-some blood removed from left atrium and travels through machine and perfuses lower extremities 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
133
left heart bypass circuit parts
tubing | centrifugal pump
134
indication of left heart partial bypass
open descending thoracic aortic aneurysm repair
135
what perfuses the head during partial left heart bypass
the heart
136
what perfuses the lower body during partial left heart bypass
arterial cannula
137
left/right heart bypass advantages 5
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
138
what does lower circuit prime volume lead to? 3
less hemodilution less blood damage less heparinization needed
139
what is the target ACT?
150-200 seconds
140
what are the % chance of renal failure for left heart bypass, simple cross clamp, and CPB?
left- 4% simple- 9% CPB- 11%
141
left/right heart bypass disadvantages
no blood or fluid can be added to the bypass system (without reservoir) pt cant be warmed or cooled by machine air embolization may be more likely
142
right heart bypass 4
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
143
why is there a lower stroke risk with right heart bypass
no aortic cross clamp is needed
144
3 indications for right heart partial bypass
tricuspid valve repair pulmonic valve repair right ventricle assist device (RVAD) placement
145
when on right heart partial bypass the surgeon can complete surgery without: (3)
arresting heart clamping aorta using oxygenator
146
where do they place the cross clamps for ascending or aortic arch aneurysms?
proximal and distal to aneurysm
147
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?
deep hypothermic circulatory arrest (DHCA) retrograde cerebral perfusion antegrade cerebral perfusion ** yes you can use more than one of these techniques
148
deep hypothermic circulatory arrest
perfusionist makes pt so cold that oxygen demands are so low they can survive a short amount of time without perfusion
149
indications for DHCA
ascending aorta repair aortic arch repair descending aorta repair clipping certain complex brain aneurysms
150
how does the circ arrest process work?
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
151
during circ arrest where is the arterial cannula placed?
femoral artery or axillary artery
152
what is the target temp before starting circ arrest?
15 to 17 degrees C | longer the operation they may need to be colder
153
what monitors are used to monitor the depth of hypothermia and ensure electrial silence during DHCA
BIS and EEG
154
when is the EEG usually isoelectric?
between 15-20 degrees C
155
how much longer is the patient cooled after they are isoelectric?
10 minutes to ensure homogenous cooling of brain
156
how long is circ arrest safe? chart
temp -- mins 20- 30-40 16- 45-60
157
circ arrest should not be performed for longer than?
60 min
158
time limit for most have no neurologic complications
<30 min
159
time limit for increased incidence of brain injury
>40 min
160
time limit for most suffer from irreversible brain damage
>60min
161
who can tolerate longer periods of circ arrest?
neonates and children
162
complications of DHCA 3
complications of hypothermia neurologic complications potential neurologic complications from cooling or rewarming pt too rapidly
163
what can rapid cooling cause
<20 min to deep hypothermia | lower neurodevelopmental outcome scores
164
what can rapid rewarming cause 4
organ damge deleterious to neurologic outcome promotes gas bubble formation (solubility decrease and temp increase) cerebral desaturation and uneven warming
165
what is the rewarming rate not to exceed?
1C core temp per 3 min of bypass time
166
when should rewarming stop?
nasopharyngeal temp reaches 35C
167
DHCA anesthetic management 2
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
what are the two temp probes to have for circ arrest?
nasal (brain) | bladder (core)
169
retrograde cerebral perfusion during circ arrest
extra perfusion line, perfuses head through SVC
170
normothermic antegrade cerebral perfusion
extra perfusion line is placed in right axillary artery to perfuse head USED WITHOUT CIRC ARREST
171
antegrade cerebral perfusion
used with normothermia or circ arrest | disadvantage: may increase incidence of stroke
172
cerebral oximetry
near infrared spectroscopy (NIRS) measure oxygen saturation in cerebral vessels (rSO2)
173
what is the normal rSO2?
60-80%
174
why is rSO2 lower than normal SO2?
cerebral vascular bed is 75% venous and 25% arterial
175
what is cerebral oximetry an indicatory of?
cerebral perfusion
176
if there is a low rSO2 value and cerebral perfusion has decreased what should you do?
increase blood flow and oxygenation to the head
177
what are two applications for cerebral oximetry
``` heart surgery (alerts the moment perfusion is disrupted to better intervene the issue) sitting/beach chair surgery (easier to know if you are perfusing the brain rather than using the BP) ```
178
when should the anesthetist intervene?
rSO2 < 50% >20% drop from baseline rSO2 difference >30% from the left and right hemispheres
179
what are the rSO2 values that correspond to poor neurologic outcomes
<45% absolute | >25% declines
180
4 factors that decrease rSO2 values
decrease in cerebral blood flow (hypotension/low CO, hyperventilation) hypoxemia anemia mechanical disturbances
181
ways to increase cerebral SpO2 (6)
``` 1- increase cerebral perfusion pressure (MAP-ICP) 2- increase cerebral blood flow 3- increase FiO2 4- increase cardiac output 5- increase hematocrit 6- decrease cerebral metabolism ```
182
ways to increase the cerebral perfusion pressure
``` increase MAP (if hypotensive) potentially decrease intracranial pressure ICP ```
183
how do you decrease intracranial pressure ICP?
mannitol- decreases CSF production, shrinks brain cell volume place lumbar drain
184
how do you increase cerebral blood flow
increase PaCO2 | nitroglycerin?
185
PT
prothrombin time examines extrinsic pathway of coagulation cascade 12-15sec
186
PTT
partial thromboplastin time examines intrinsic pathway of cascade 25-40 sec
187
INR
international normalized ratio standardized PT result 0.9-1.1
188
standard unfractioned heparin
binds and enhances activity of antithrombin III 1000 fold | effects intrinsic pathway
189
what can heparin be reversed by
protamine
190
lovenox (enoxaparin)
``` LMWH dosed subcutaneously longer lasting 12-24 hr doesnt prolong PTT as much not reversed reliably with protamine ```
191
what is the half life of standard heparin?
1 hr when dosed intravenously
192
what is a good test for lovenox
anti- Xa assay
193
coumadin
warfarin by mouth vitamin K antagonist effects extrinisic pathway effects PT and INR more
194
what can warfarin be reversed with?
FFP | vitamin K
195
plavix
clopidogrel by mouth antiplatelet not reliably reversed (usually with platelets) half life 5-7 days
196
dual antiplatelet therapy
aspirin and plavix | indicated for recent coronary balloon angioplasty or stent
197
pt that is on dual antiplatelet therapy should wait how long for elective surgery if balloon angioplasty?
at least 14 days
198
pt that is on dual antiplatelet therapy should wait how long for elective surgery if metal stent placed
at least 6 weeks
199
pt that is on dual antiplatelet therapy should wait how long for elective surgery if drug eluting stent placed
at least a year
200
what if the pt is on dual antiplatelet therapy and has to have emergency surgery?
aspirin usually continued and surgeon/cardio make plan for pt needs
201
xarelto (rivaroxiban)
by mouth direct Xa inhibitor | reversed with prothrombibn complex concentrates (PCC)
202
when should xarelto be discontinued before surgery?
at least 24 hours before
203
eliquis (apixaban)
direct factor Xa inhibitor | reversed with PCC
204
when should eliquis be discontinued before elective surgery?
at least 48 hours before
205
heparin dose for standard CPB
300-400 units/kg dosed before aortic cannulation
206
ACT
activated clotting time; blood test used to measure coagulation during cardiac surgery when heparin is given
207
normal ACT
100-150 sec
208
goal ACT prior to going on pump
>450 sec
209
heparin induced thrombocytopenia (HIT)
patients immune system has antibodies against heparin which: thrombocytopenia (lack of platelets) thrombosis (clotting) usually occurs with standard heparin
210
what is used for anticoagulation in patients that have HIT?
direct thrombin inhibitors (argatroban) | more difficult to control post op bleeding
211
antithrombin III deficiency
low levels of ATIII and show resistance to heparin | can be acquired as a result of recent heparin administration
212
anesthetic management of ATIII deficiency
``` replaced AT III (concentrates available) administer FFP (if concentrates are not available) ```
213
protamine
salmon sperm reverses heparin brings ACT back to normal
214
when is protamine given during cardiac surgery?
when the pt is taken off bypass
215
dose of protamine
1mg per 100 units heparin
216
how is heparin given?
peripherally and slowly over 10 min
217
protamine mechanism of action
binds heparin and it is no longer bound to ATIII
218
what does protamine do when given without prior administration of heparin?
it is an anticoagulant
219
what could excess protamine cause?
increase bleeding especially in thrombocytopenia or low VIII
220
2 adverse effects of protamine
(with rapid/central admin) hypotension anaphylactoid reaction
221
when is a anaphylactoid reaction to protamine more likely?
prior exposure to protamine allergic to fish male pts with vasectomy diabetics exposed through insulin
222
why does a male with vasectomy have reaction to protamine?
because they can develop antibodies to sperm
223
what reverses the effects of warfarin?
FFP and vitamin K FFP and PCC work quickest but they dont reverse they just replace the clotting factors vitamin K will help the patient make their own clotting factors
224
Prothrombin Complex Concentrates (PCC)
contains vitamin K dependent clotting factors | reverse the effects of coumadin, xarelto, eliquis
225
What can PCC replace in massive transfusion protocol?
FFP
226
how much higher of a concentration are the clotting factors in PCC compared to FFP
25 fold higher
227
1 vial of PCC= _?__ units FFP?
2
228
advantages of PCC
twice as fast as FFP single dose every 24 hours (less volume required) half the adverse effects of FFP faster prep time (no thawing)
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disadvantages of PCC
20x more expensive shorter acting than FFP (should be administered with vitamin K)
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FFP vs PCC???
jury still out some studies say half blood products used for PCC some studies say higher mortality rate at 45 days for PCC