Anesthesia for Cardiothoracic Procedures Flashcards
1
Q
3 types of Cardiothoracic surgery
A
- open heart surgery (sternotomy/ thoracotomy)
- Da Vinci (laparoscopic)
- endovascular (valve repair/ aortic repair)
2
Q
What does “invasive” cardiac surgery refer to?
A
sternotomy
-best exposure but most possible complications
3
Q
3 cardiac surgeries considered minimally invasive
A
- Da Vinci
- Thoracotomy
- Endovascular
4
Q
Minimally invasive cardiac surgery is aka?
A
MICS
5
Q
What kind of endotracheal tube may be used in a MICS?
A
Double lumen
-one of the lungs may need to be deflated
6
Q
Can MICS be performed “off pump”?
Bypass can be instituted with cannulation through which vessels?
A
Yes;
femoral vessels
7
Q
Which is more common for Aorta surgery?
- Invasive open repair with cross clamps
- minimally invasive endovascular repair
A
- minimally invasive endovascular repair
8
Q
How is a MICS CABG performed?
- what incision?
- commonly performed on or off pump?
A
- thoracotomy incision
- reserved for 1 or 2 vessel disease due to limited exposure of anterior vessels - off pump
- bypass via femoral vessels can be an option
9
Q
in a DaVinci CABG procedure, what is the main purpose of the robot?
A
to harvest the LIMA
10
Q
in a DaVinci CABG procedure, after the LIMA is harvested, how is the graft sewn on?
A
Through a small thoracotomy incision
11
Q
an operation in which the anterior vessels are bypassed with a MICS/thoracotomy approach (by a cardiac surgeon) and the more difficult to expose vessels are stented (by an interventional cardiologist)
A
Hybrid coronary revascularization
12
Q
What is the benefit of Hybrid coronary revascularization?
A
allows multiple CAD to be performed without sternotomy while still allowing a LIMA to LAD graft
-superior to intravascular stent placement
13
Q
Hybrid rooms are utilized for which 2 procedures?
A
- hybrid coronary revascularization
2. transcatheter aortic valve replacement/ transcatheter aortic valve implantation
14
Q
Hybrid rooms are utilized for procedures that use which 2 types of doctors?
A
- cardiac surgeon
2. interventional cardiologist
15
Q
Because CABG patients have CAD, the goal is to avoid which two occurrences?
Do we premedicate for CABG patients?
A
- anxiety
- tachycardia
Yes: Give higher dose of Midazolam
Patients undergoing CABG require heavier medication than valve replacement
16
Q
Are stenotic heart valves typically replaced or repaired
A
replaced
-leads to better outcomes
Repairs involve removal of calcifications
17
Q
Are regurgitant heart valves typically repaired or replaced?
A
Repaired
- although both repaired and replaced can be done
18
Q
Do we premedicate for valve repair/replacement patients?
why or why not?
A
NO:
Premedication can lower blood pressure and cause vasodilation = reduced preload and afterload
Patients for valve repair need to maintain preload/afterload
19
Q
In MICS valve repair/replacement surgeries:
are they most commonly performed On or Off pump?
If on pump, where are the cannulation sites?
A
on pump
femoral vessels
20
Q
Can valve repair/replacments be done with the Da Vinci robot?
A
yes
-bypass is possible via femoral vessels
21
Q
What are 6 surgical ways in which valves may be repaired or replaced
A
- MICS
- Da Vinci
- Endovascular (off pump)
- Full Bypass with an arrested/beating heart
- Right heart bypass for pulmonic/tricuspid valves
- Transapical (off pump)
22
Q
When would we consider using an endovascular valve repair technique?
A
in patients who do not qualify for open heart surgery
23
Q
Endovascular aortic valve replacement is referred to as what 2 names?
A
- Transcatheter aortic valve replacement (TAVR)
2. Transcatheter aortic valve implantation (TAVI)
24
Q
What are the 2 catheter/stent pathways for TAVR and TAVI?
Which is most common?
A
- femoral artery to aortic valve (most common)
2. axillary artery to aortic valve
25
What is the catheter/stent pathway for endovascular mitral valve repair?
femoral vein to intra-atrial septum to mitral valve
26
What is the catheter/stent pathway for tricuspid and pulmonic valve repair?
femoral vein, passes through the right side of the heart to the valve
27
A form of TAVR/TAVI that is the only example of a valve replacement being performed “off pump” with an “open” approach
Transapical valve replacement
-mini thoracotomy
28
6 risks associated with Endovascular TAVR
1. Associated with a higher risk of this compared to surgical replacement
2. What type of leak?
3. the most frequent adverse outcome associated with TAVR and can lead to life threatening hemorrhage
4. risk is due in part to the large contrast load used in placing the valve with fluoroscopy
5. What type of cardiac conduction abnormalities?
6. What type of post op complications?
1. stroke/ TIA
2. perivalvular leak
- aortic regurge
3. vascular complications
- perforation, dissection, rupture in the arteries
4. Acute kidney injury
5. mechanical impingement of the conduction system leading to LBBB
- complete heart block in patients with existing RBBB
6. bleeding and atrial fibrillation
29
What approach can limit vascular complications during Endovascular TAVR be limited?
transapical thoracotomy approach
30
anesthetic management of TAVR
1. What 2 things should be administered for Renal Protection (because of contrast dye used)
1. perioperative volume loading
| - administration of N-acetylcysteine prior to surgery
31
when keeping the heart still during valve deployment, what major hemodynamic event will occur?
Do you treat this?
hypotension
- surgeon may or may not request treatment
- valve deployment is quick (12 s) and if treated could cause a rebound hypertension and increase valvular regurge
32
Anesthetic management for TAVR:
2. What should be used for Stroke Prevention and for how long?
What therapy should be used for TAVI?
2. Dual antiplatelet therapy (aspirin and clopidogrel) started before the surgery and continued for 6 months
- TAVI: loading dose of 300-325mg of aspirin and 300mg of clopidogrel before the surgery
33
Anesthetic Management of TAVR:
3. (low/high) dose of heparin and what is the goal ACT?
low dose of heparin with an ACT goal of >250
34
Anesthetic Management of TAVR:
4. Two reasons for placement of transvenous placement leads
4. establish rapid ventricular pacing during valve deployment
- can pace the heart in case of heart block following the procedure
35
Anesthetic Management of TAVR:
5. Placement of these can treat life threatening arrhythmias
5. external defibrillator pads
36
Anesthetic Management of TAVR:
6. Purpose of TEE?
6. provides info about the results of the balloon valvuloplasty and the position of the prosthetic valve and may identify procedure related complications
37
Anesthetic Management of TAVR:
7. Amicar administration (is/ is not) necessary
7. Amicar Is NOT necessary
38
Anesthetic Management of TAVR:
8. Two options to keep the heart still during valve deployment
8. a. Rapid ventricular pacing at a rate of 180-220 bpm (temporary cessation of CO)
and reduction of systolic BP below 60 mmHG
b. stopping the heart with 12mg of adenosine
39
Anesthetic Management of TAVR:
9. 3 Hemodynamic goals for patients with aortic stenosis
Preload/afterload?
HR?
ECG?
1. Preload augmentation
2. Low HR (50-70 bpm)
- allow adequate diastolic filling time
3. maintenance of normal sinus rhythm
40
Anesthetic Management of TAVR:
10. What continuous postop monitor should be used and for how long after?
10. continuous electrocardiogram monitoring for 48 hours post-op
41
3 things for Endovascular Aortic Management
1. no sternotomy/ bypass
2. less heparin
3. no Amicar
42
this technique of aortic surgery is the most common
endovascular
| -more common than open
43
How is an aortic root replacement surgery performed?
traditional bypass with an arrested heart
| - a clamp can be placed on the ascending aorta
44
Surgical techniques for open ascending aorta repair:
If a clamp can be placed on the ascending aorta, what technique can be used?
traditional bypass (without circ. arrest)
45
Surgical techniques for open ascending aorta repair:
If the aneurysm extends into the aortic arch, what 2 techniques can be used?
1. deep hypothermic circ. arrest
- with or without antegrade or retrograde perfusion
2. normothermic antegrade perfusion
46
What is the problem with open descending open aorta repair?
It is not possible to perfuse both the head and lower extremities with one perfusion cannula
47
What 3 techniques can be used for open descending aorta repair?
1. partial cardiopulmonary bypass
2. left heart partial bypass
3. Circ. arrest
- decreases the risk of post-op organ dysfunction and paralysis
48
Open descending aorta repair with aortic clamps:
Blood flow to the head is provided by?
Blood flow to the body is provided by?
left ventricle
bypass machine
49
Open descending aorta repair:
Clamps on the descending aorta increase the chance of _____ from inadequate perfusion of the spinal cord
paralysis
50
Descending Aorta Repair with Partial CPB:
SOME blood is removed from the ____ _____ through the venous cannula, travels to the bypass machine, and perfuses the ____ _____
```
right atrium
lower extremities (distal to the clamp)
```
51
Descending Aorta Repair with Partial CPB:
SOME blood stays in the heart and goes to the _____ before being pumped into the left ventricle and aorta to perfuse _____ and ______.
lungs
| head, upper extremities (proximal to the clamp)
52
In Descending Aorta Repair with Partial CPB, does the oxygenator need to be used?
YES
53
Descending Aorta Repair with Left Heart Partial Bypass:
SOME blood is removed from the ____ _____ through a reservoir cannula, travels to the bypass machine, and perfuses the ____ _____ through the arterial cannula
```
left atrium
lower extremities (distal to the clamp)
```
54
Descending Aorta Repair with Left Heart Partial Bypass:
SOME blood stays in the heart and is pumped to the ____ to perfuse the _____ and _____.
aorta
| head, upper extremities (proximal to the clamp)
55
Anesthetic Considerations for Left Heart Bypass:
1. hemodynamics for left heart bypass with partial CPB
1. Shared circulation in place by both the anesthetist and the perfusionist
- perfusionist can divert too much blood from the heart and deprive the heart, brain, and upper extremities of adequate blood supply
56
Anesthetic Considerations for Left Heart Bypass:
2. What is measured to assess pressure distal to the clamp?
where should this be placed?
2. arterial pressure
| Right radial artery and femoral artery
57
Anesthetic Considerations for Left Heart Bypass:
If arterial pressure is too high proximally and too low distally, what does this mean?
Flow should be INCREASED through the CIRCUIT
58
Anesthetic Considerations for Left Heart Bypass:
If arterial pressure is too low proximally and too high distally, what does this mean?
Flow should be LOWERED through the CIRCUIT
59
Anesthetic Considerations for Left Heart Bypass:
If proximal arterial pressure and distal arterial pressure are both low, what should you do?
administer fluids or vasoconstrictors
60
Anesthetic Considerations for Left Heart Bypass:
If proximal arterial pressure and distal arterial pressure are both high, what should you do?
administer a vasodilator
61
Anesthetic Considerations for Left Heart Bypass:
3. Filling of the ventricles should be assessed by what two pressures?
CVP should be compared to PA diastolic or PCWP
62
Anesthetic Management for Open Descending Aorta Repair:
1. Where should the arterial line be placed? Why?
1. RIGHT arm
| - clamping proximal to the left subclavian artery may be necessary
63
Anesthetic Management for Open Descending Aorta Repair:
2. What type of ETT should be used? Why?
2. Double Lumen Tube
| - Thoracotomy approach may be used
64
List 4 specific Anesthetic Management for Open Descending Aorta Repair
1. Place the arterial line in the Right arm
2. Double Lumen Tube
3. Prepare standard cardiac drugs
4. consider techniques for spinal cord protection
65
List 4 possible Spinal Cord techniques for Open Descending Aortic Repair
1. SSEP/ MEP monitoring
2. Lumbar Drain
- increases spinal cord perfusion pressure
3. Steroids
- decrease swelling
4. Mannitol
- increases spinal cord perfusion (Decrease CSF production)
- increases renal perfusion (beneficial when aorta is clamped)
66
What is the equation for spinal perfusion pressure
MAP- CSF pressure
67
What is an aortic wrapping procedure?
Is it an open or closed chest procedure?
What is it primarily used to treat?
What patients is this reserved for?
Sleeve wrapped around the external Aorta
Open chest procedure
Primarily used to treat aortic aneurysm
Less common; used for patients already undergoing aortic valve replacement but are too high risk for ascending aortic replacement
68
This heart transplant approach requires replacing the recipient heart with the donor heart
Orthotopic
69
After the donor heart is removed, how long do you have until it needs to be placed into the recipients body?
4-5 hours
70
What are 3 types of Orthotopic heart transplants?
1. Biatrial
2. Bicaval
3. Total
71
Hear transplant approach where the donor heart is placed in the right chest alongside the recipient organ, and anastomosed in such a way as to allow blood to pass through either or both hearts
Heterotropic (piggyback)
72
What is a Biatrial heart transplant?
Only the ventricles are removed
73
A biatrial heart transplant requires how many anastomosis?
4
74
What is a bicaval heart transplant?
ONLY the entire right atrium is removed
| - but the left atrium stays intact
75
In a biatrial heart transplant, where will the anastomoses be with the donor and recipient heart?
midatrial level
76
In a bicaval heart transplant, the right side of the donor heart will attach to the right side of the patients heart with anastomosis where?
at the SVC and IVC
77
a bicaval heart transplant requires how many anastomosis?
5
78
What is a total heart transplant?
Removing ALL of the heart, including the left atrium
79
How many anastomosis does a total heart transplant require?
6
80
2 primary advantages of the biatrial technique
1. shorter operation times (less anastomosis)
| 2. less anastomotic complications
81
disadvantage to a biatrial technique
higher risk of post-op arrythmias, atrial enlargment, thrombi, tricuspid valve regurge
82
Which as better post-op function? Biatrial heart transplant or total transplant
total transplant
| -just longer operation times
83
In normal patients, atropine and robinul ______ HR through parasympathetic input
increase
| -block Ach from binding to to postjunctional muscarininc receptors on the SA node
84
What does a "denervated" heart mean?
a heart that is no longer connected to sympathetic or parasympathetic stimulation (including vagus nerve)
85
A patient that has had a heart transplant has a (higher/lower) normal resting HR
higher
86
In heart transplant patients, do atropine and robinul speed up the HR?
no
| -no Ach from presynaptic receptors released
87
What does neostigmine do?
floods the body with Ach and goes to SA node to cause bradycardia
88
Can neostigmine cause bradycardia in a patient with a heart transplant?
yes
| -floods the body/ SA node with Ach
89
When is the only time Atropine and Robinul work on a patient with a heart transplant?
When neostigmine is given
| -prevents neostigmine induced bradycardia
90
What happens to a patients right ventricle who has heart failure with pulmonary hypertension?
Right ventricular hypertrophy
| -pump against the pulmonary resistance
91
Patients with heart failure and pulmonary hypertension have a (weak/strong) left ventricle and a (weak/strong) right ventricle
weak left ventricle= low cardiac output
| strong right ventricle
92
What heart transplant procedure is best for patients with pulmonary hypertension?
Heterotropic heart transplant
- Old original heart has strong right ventricle to push against pulmonary hypertension
- new donor heart has strong left ventricle to increase CO
93
Implications of "Denervation":
1. Resting heart rate?
Resting Heart Rate is typically faster( >90 bpm)
| -loss of vagal tone
94
Implications of "Denervation":
2. Atropine and Robinul?
Atropine and Robinul will not work to increase HR
95
Implications of "Denervation":
3. Neostigmine?
Neostigmine will cause bradycardia
| -antimuscarinics (anticholinergics) can reduce neostigmine induced bradycardia
96
Implications of "Denervation":
4. How is bradycardia treated?
-pacing wires or beta-1 agonists
| isoproterenol, dobutamine, Epi, Norepi
97
Implications of "Denervation":
5. Can the patient still experience angina?
no
98
Implications of "Denervation":
6. baroreceptor reflex?
Does not work
| - no changes in HR with BP and no reflex bradycardia
99
Implications of "Denervation":
7. Sympathetic nervous system?
Sympathetic re-innervation can occur within 12 months of the operation
- varies
- parasympathetic is less likely
100
Implications of "Denervation":
8. What is cardiac output due to?
Increase in STROKE VOLUME
| - NOT HR
101
Implications of "Denervation":
9. Which Heart transplant technique shows 2 P waves on the ECG?
Biatrial
| -SA node of recipient stays intact and Patient will have another SA node from donor
102
Which SA node determines the HR in a biatrial heart transplant: the donor's (new) or the recipient's (old)?
The donor's (new)
103
Anesthetic Management for Heart Transplant Procedure:
1. PA pressures?
1. PA pressure should be kept low
104
List 4 strategies to reduce PAP in a heart transplant procedure
1. Hyperventilation
2. high FiO2
3. pulmonary vasodilators (nitrates, prostaglandin, nitric oxide)
4. avoid acidosis
105
Anesthetic Management for Heart Transplant Procedure:
2. Inotropes?
Yes,
| -more likely to be needed than in other heart procedures
106
Anesthetic Management for Heart Transplant Procedure:
3. Immunosupressive therapy?
-most regimens include triple therapy of azathioprine, cyclosporine, corticosteroids
107
What is a common drug that is used to prevent transplant rejection and when is it dosed?
Methylprednisolone: steroid
| -dosed right after release of the cross clamps
108
Anesthetic Management for Heart Transplant Procedure:
4. Hyperkalemia/ hypokalemia?
Hyperkalemia post transplant
- preservative solution is rich in K+
- consider ways to lower K+ prior to anastomosis
- hyperventilation?
109
Where are bypass venous cannulas placed in heart transplant?
SVC and IVC
| -standard CPB case
110
What is transmyocardial revascularization (TMR)?
laser creates a series of holes in the myocardium
111
What is the primary purpose of TMR?
relieve angina in patients not eligible for bypass or angioplasty
(small vessel coronary disease or who don't have any grafts)
112
2 theories for how TMR works
1. stimulates angiogenesis
- creates new channels for blood flow
2. Destroys nerve endings associated with angina
113
Anesthetic considerations for TMR:
1. used in combo with what procedure?
1. used in combo with CABG to compensate for ungraftable areas of the heart
114
Anesthetic considerations for TMR:
2. When done by itself, what is the surgical technique?
What 2 things are required from an anesthesia standpoint?
2. Left anterior thoracotomy
| - requires a double lumen tube and left lung isolation
115
Anesthetic considerations for TMR:
3. when the laser is applied and when the surgeon applies pressure to stop the bleeding, what 2 things can be expected?
What 3 drugs should be available to treat this?
1. arrhythmias and a decrease in CO
Anti-arrhythmias, inotropes, vasopressors
116
What is a pericardial effusion?
fluid around the heart or accumulation of fluid in the pericardial cavity
117
What is cardiac tamponade?
What risks are associated with this?
when pericardial effusion gets large enough to adversely affect heart function
- decreased EF
Severe hypotension and Cardiac arrest
118
What are the 2 Hemodynamic effects of Cardiac Tamponade?
1. decreased CO
2. Becks Triad
- hypotension
- jugular venous distension
- muffled heart tones
119
What are 2 treatment options for Cardiac Tamponade?
1. pericardiocentesis
- can be done under local/sedation
2. Pericardial window
- done under GA
- VATS approach
- Subxiphoid approach
120
Anesthetic Management for Pericardial Window:
1. Type of anesthesia?
1. General or MAC with subxiphoid under local and sedation
121
Anesthetic Management for Pericardial Window:
2. Approach for an emergency? (impending cardiac tamponade)
Approach if patient is stable?
2. Subxiphoid is quickest and utilized in an emergency
- airway with single lumen ETT
Thoracotomy Approach if patient is stable
-lung isolation with double lumen ETT or bronchial blocker
122
Anesthetic Management for Pericardial Window:
3. Induction of Anesthesia in unstable patients
3. head of bed should be elevated 45 degrees to decrease dyspnea
- avoid propofol (ketamine or etomidate should be used)
- surgeon is scrubbed and gowned prior to induction
123
Anesthetic Management for Pericardial Window:
4. HR?
Bradycardia should be avoided!
| -Cardiac output is dependent on HR (like pediatrics)
124
Anesthetic Management for Pericardial Window:
5. Ventilation?
Spontaneous ventilation should be maintained
- PPV will decrease venous return and CO
- awake fiberoptic intubation can be considered to avoid PPV
125
This procedure enables visualization of the contents of the space between the lungs inside the chest (mediastinum), usually for the purpose of obtaining a biopsy to rule out types of cancer
Mediastinoscopy
126
In a mediastinoscopy, the scope can compress which artery?
brachiocephalic = innominate
127
Where does the innominate artery supply blood?
Right arm and right common carotid
128
Which patients are at risk for cerebral ischemia during a mediastinoscopy?
Patients with Left carotid stenosis
129
What type of ETT is used for a mediastinoscopy?
single lumen tube
130
Where is the arterial line most COMMONLY placed in a mediastinoscopy?
What do you need on the other arm?
Right arm
-inform the surgeon when compressing the innominate artery
NIBP on left arm
- to monitor BP when innominate is being compressed
131
It is mandatory to monitor pulse in which arm during mediastinoscopy?
right arm
-can use Spo2 on right arm and arterial line on left arm (continual BP but not common)
132
What is the primary concern with mediastinal mass?
```
compression of vital structures
1. Heart
2. trachea
3. bronchi
4 Central blood vessels
```
133
3 symptoms of mediastinal mass causing SVC obstruction
1. decreased CO
2. airway/ facial edema
3. increased ICP
134
What is superior vena cava syndrome
When a patient shows signs/ symptoms of superior vena cava obstruction
135
What is the most common cause of SVC syndrome?
malignancy
136
What is Pemberton's sign?
When a patient experiences facial congestion, cyanosis, and possible respiratory distress after raising both arms in the air
- caused by venous obstruction usually in patient with goiters
- shows that positioning can cause or alleviate obstruction from the mediastinal mass
137
What type of ventilation is better with patients who have Tracheobronchial compression with a mediastinal mass?
spontaneous ventilation
-mechanical ventilation should only be used if tube is distal to obstruction and pt can tolerate
138
How should the anesthetist intubate someone with trachobronchial obstruction from a mediastinal mass?
Intubate distal to the obstruction
-surgical intervention may be necessary with tracheal/bronchial stenting with rigid bronchoscopy
139
What is jet ventilation?
The use of high pressure to ventilate a patient through a small catheter or stricture in the airway
-hooked up to oxygen wall supply and administered with lever
140
Anesthetic Management for Mediastinal Mass
1. Diagnostic tests?
1. CT scan
- best for assessing tracheal compression
Chest XR
Echocardiogram
-used to evaluate direct compression of the heart
Pulmonary function tests
141
When the cross-sectional area of the trachea is ____% of normal, there is a high incidence of complications with GA
<50%
142
Anesthetic Management for Mediastinal Mass:
If the patient has______ significant abnormal findings in CT, spirometry, or ECHO, there is a significant risk of complications from GA
2 or more
-tumor should be shrunk with steroids or radiation prior to GA
143
Anesthetic Management for Mediastinal Mass:
2. Ventilation?
spontaneous ventilation
| -avoid complete airway obstruction
144
Anesthetic Management for Mediastinal Mass:
3. Intubation?
Awake fiberoptic intubation in the sitting position if patient is symptomatic
-safest and most reversible
145
Anesthetic Management for Mediastinal Mass:
4. ETT?
Armored (reinforced) ETT
| -embedded wire coil which keeps the tube from getting kinked or compressed
146
Anesthetic Management for Mediastinal Mass:
5. 2 things to avoid if not doing an awake intubation
1. hypotension
- need to maintain Cerebral perfusion pressure
2. Cardiovascular collapse on induction
147
Anesthetic Management for Mediastinal Mass:
Advantage of inhalation induction
Disadvantage of inhalation induction
patient remains spontaneously ventilating
may precipitate an airway obstruction
148
Anesthetic Management for Mediastinal Mass:
When is a routine induction used?
When patients show no clinical signs or symptoms of airway or cardiovascular compression
-performed with/without ketamine
149
Anesthetic Management for Mediastinal Mass:
6. If SVC syndrome, where should IV's be placed?
Place IV's in lower extremities
-maintain preload
150
Anesthetic Management for Mediastinal Mass:
7. Immediate surgical interventions?
In case of sudden airway or cardiovascular collapse:
GA: arterial line and and heart team on standby with patient's groin prepped for CPB
151
Anesthetic Management for Mediastinal Mass:
It is recommended that in all patients with more than____ reduction in caliber of the airway preoperatively,_____ vessels should be cannulated in the preparation of cardiopulmonary bypass before the induction of general anesthesia
50%
| femoral
152
Anesthetic Management for Mediastinal Mass:
If cardiovascular collapse occurs, what should you do?
attempt to reposition the patient to alleviate mediastinal mass
153
What is laser lead extraction?
laser sheaths are guided over pacing wires to remove tissues surrounding the leads allowing a more safe pacing wire removal
-prevents tearing of heart tissue from encapsulated pacing leads
154
What 2 things are necessary in laser lead extraction?
1. arterial line
- in case of severe hypotension
2. cardiac team on standby
- in case of severe hemorrhage
