Anesthesia for Congenital Heart Disease Flashcards
1
Q
____ refers to a normal opening in the body that has been narrowed or closed
A
atresia
2
Q
______ means “narrowing
A
coartication
3
Q
another name for right ventricular hypertrophy (RVH)
A
cor pulmonale
4
Q
____ a muscle below the pulmonic valve
A
infundibulum
5
Q
to an operation that is intended to decrease the severity of symptoms until a patient can tolerate an operation that will fix their condition
A
palliative surgery
-An example of a palliative operation would be placement of a Blaylock-Taussig (BT) shunt to keep a child alive until they are old enough to better tolerate an operation to repair their tetralogy of Fallot (TOF)
6
Q
an artificial connection between the aortic arch and the pulmonary artery
aka an artificial ductus arteriosus
A
BT shunt
-It allows blood to get into the lungs from the aorta, and can be placed in patients that have reduced blood flow to the lungs (ex: pulmonary stenosis)
7
Q
The risk of ______ remains a major concern in patients with congenital heart disease (CHD), whether unrepaired, palliated, or corrected
A
infective endocarditis (IE)
- Abx prophylaxis has long been recommended in patients with a history of congenital heart disease who need to undergo operations
8
Q
Many patients with congenital heart disease suffer from hypoxia, and in an effort to compensate for the hypoxia, they make more red blood cells (which can cause them to have an abnormally high hematocrit)
The abnormally high hematocrit is referred to as ______
A
compensating polycythemia
- these patients are more prone to thrombosis
- generous fluid replacement can be beneficial because it can help bring the hematocrit level back to normal
9
Q
A “normal” embolism will travel to the lungs and stay on the (right/left) side of the heart/pulmonary artery
A
right
10
Q
A “paradoxical” embolism is an embolism that travels to the (right/left) side of the heart (through an ASD or a VSD) and ends up in the arterial circulation (and most likely causes a stroke)
A
left
11
Q
If patients have a heart condition where blood shunts (right to left/ left to right) across an ASD or VSD, the risk of paradoxical embolism increases substantially, which means anesthetist need to be very vigilant in not allowing any air bubbles to in an IV line
A
right to left
12
Q
increases in SVR promote more _____ shunting and (increase/ decrease) pulmonary blood flow
A
left to right
increase
13
Q
decreases in SVR promote more ______ shunting and (increase/decrease) pulmonary blood flow
A
right to left
decrease (can lead to hypoxia)
14
Q
increases in PVR promote more ______ shunting and (increase/ decrease) pulmonary blood flow
A
right to left
decrease (worsen hypoxemia)
15
Q
decreases in PVR promote more _____ shunting and (increase/ decrease) pulmonary blood flow
A
left to right
increase
16
Q
How can we decrease PVR?
A
higher FiO2 and hyperventilation
17
Q
How can we increase PVR?
A
lower FiO2 and hypoventilation
18
Q
Because of the hypoxia, patients with right to left intracardiac shunts are more prone to _______ than are patients with left to right intracardiac shunts
A
compensating polycythemia
19
Q
is inhalational induction faster or slower in right to left cardiac shunts?
A
slower
Blood from the right side is entering the left side without having picked up any inhalational anesthetic
This dilutes the vapor in the arterial blood
20
Q
is IV induction slower or faster in right to left cardiac shunts?
A
faster
Drugs get to the left side of the heart faster
21
Q
How should the anesthetist manage SVR and PVR in right to left shunting?
A
Increase SVR
- regional and general anesthesia should be titrated slowly
- use ketamine
- single spot spinal is CONTRAINDICATED
Decrease PVR
22
Q
What type of cardiac shunting are IV bubbles the most dangerous?
A
right to left shunting, however left to right shunting can turn into right to left shunting which makes it equally as dangerous (Eisenmenger’s syndrome)
23
Q
What is “Eisenmenger’s syndrome”?
A
the left to right shunts can convert to a right to left shunt
24
Q
before birth, blood shunts ________across the PDA
A
right to left
25
How is inhalational induction changed in left to right shunts?
Anesthetic induction is minimally affected
26
how is IV induction changed with left to right shunts?
slightly prolonged IV induction
| -Probably due to the drug being slightly diluted
27
How should the anesthetist manage a left to right cardiac shunt?
increase PVR
decrease SVR
28
after birth, blood shunts ______ across the PDA
left to right
29
Assuming no other defects are present, blood is expected to shunt in a ______ fashion in patients with a PDA, leading to increased _______
left to right
| pulmonary blood flow/ pulmonary congestion
30
Patients with a PDA often exhibit (high/ low) diastolic blood pressure
low
| - some blood falls back into the pulmonary system during diastole
31
in patients with a PDA, how should the anesthetist control shunting?
decrease left to right shunting
| good preload, lower FiO2, slight hypoventilation
32
what is indomethacin used for?
used to close the PDA
-up to 3 doses
33
to blood flow to areas of the body PROXIMAL TO THE DUCTUS ARTERIOSUS
preductal circulation
34
blood flow to areas of the body DISTAL TO THE DUCTUS ARTERIOSUS
postductal circulation
35
if the PDA connects distal to the subclavian artery, preductal circulation includes?
1. head
2. right arm
3. left arm
36
if the PDA connects distal to the subclavian artery, postductal circulation includes?
1. abdomen
| 2. lower extremities
37
if the PDA connects proximal to the subclavian artery, preductal circulation includes?
1. head
| 2 right arm
38
if the PDA connects proximal to the subclavian artery, postductal circulation includes?
1. left arm
2. abdomen
3. lower extremities
A paradoxic air embolism in this situation becomes much more likely
39
in order to obtain a preductal blood sample, the anesthetist should use?
right radial artery
40
in order to obtain postductal blood sample, the anesthetist should use?
femoral, dorsalis pedis, or posterior tibial artery
41
What does it suggest if preductal oxygen saturation is significantly different from postductal oxygen saturation?
suggests a heart defect that includes right to left shunting across a PDA that is causing hypoxemia in the postductal circulation
42
What is a patent foramen ovale?
the foramen ovale never closed after birth like it was supposed to
43
What is the anesthetic management for patent foramen ovale:
1. the anesthetist should (decrease/increase) left to right shunting
2. the anesthetist should not allow any _____ in the IV tubing
1. decrease
- good preload, lower FiO2, slight hypoventilation
2. air bubbles
44
a hole between the right and left atria, so it can kind of be considered a “larger” patent foramen ovale
ASD
45
How should patients with an ASD be anesthetically managed?
same way as patients with a PFOs and PDAs
| decrease left to right shunting
46
hole between the left and right ventricles
VSD
47
What is the most common congenital cardiac defect in adults?
VSD
48
How should patients with a VSD be anesthetically managed?
same as ASD, PFO, and PDA
| decrease left to right shunting
49
a malformation of the tricuspid valve that results in tricuspid regurgitation
Ebstein's Anomaly
-eventually results in high right atrial pressure & right atrial enlargement
50
2 problems with Ebstein's anomaly
1. heart defect?
2. which way will blood shunt?
1. the increase in right sided heart pressures makes it 80% more likely an ASD will be present
2. If an ASD were present, blood would most likely shunt right to left
- decrease pulmonary blood flow, increase hypoxia, and increase the chances of a paradoxic air embolism and compensating polycythemia
51
How should Ebstein's anomaly be managed?
| 1. decrease or increase PVR?
1. decrease PVR
52
What is the main problem with Eisenmenger's physiology/
pulmonary blood flow is 4X greater than systemic blood flow
53
What is the anesthetic management of Eisenmenger's physiology?
1. SVR? PVR?
maintain SVR and PVR
-because a disruption one way or the other could cause a reversal of the shunt, leading to either heart failure or cyanosis
54
a narrowing of the aorta DISTAL to the left subclavian artery
coarctation of the aorta
| -Postductal coarctation is more common
55
What are the 3 main problems with coarctation of the aorta?
1. decreased cardiac output
- poor peripheral perfusion, high afterload, congestive heart failure, aortic regorge
2. risk for aortic dissection
3. blood pressure in the lower extremities will be lower than the upper extremities
56
4 things for Anesthetic management for coarctation of the aorta
1. Preload should be maintained to ensure adequate forward flow
2. avoid high heart rate due to aortic dissection
3. SVR should be maintained, low afterload avoided
4. avoid bradycardia
- The left ventricular stroke volume (due to the coarctation) is even more fixed, meaning that cardiac output can only be increased if the heart rate increases
57
a condition in which the aorta isn’t fully developed, and the patient ends up with a gap between the ascending and descending aorta
interrupted aortic arch
58
With an interrupted aortic arch, the proximal aorta is perfused with ______
oxygenated blood from the left ventricle
This usually consists of blood flow to the head and right arm. In other words, the head and right arm should have a normal blood pressure and SpO2
59
in interrupted aortic arch, the distal aorta/ lower extremities are perfused with _______
mixed venous/ arterial blood coming from the right ventricle through a PDA
-This means that the lower extremities will have a lower SaO2, and most likely a lower blood pressure as well
60
in interrupted aortic arch, what must be present in order for the lower extremities to receive oxygen?
VSD (left to right shunt= pulmonary congestion)
| -The VSD allows oxygenated blood from the left side of the heart to mix on the right side before going out to the body
61
What is the anesthetic management for interrupted aortic arch? (2)
1. keep PDA patent
- only thing allowing lower extremity blood flow
2. maintain an appropriate PVR/ SVR balance
- Allowing left to right shunting across the VSD is what allows oxygen to get to the lower extremities, but too much left to right shunting can cause pulmonary congestion
62
What 4 defects are present in tetralogy of fallot (TOF)?
1. pulmonic stenosis (right ventricular outflow tract obstruction)
2. right ventricular hypertrophy
3. VSD
4. overriding aorta
63
in TOF, which way does blood shunt across the VSD?
right to left
64
in TOF, what ventricle does an "overriding aorta" arise from?
both ventricles (sits directly above the VSD)
65
anytime an overriding aorta is present, the patient will be perfused with _______ blood
mixed venous/arterial blood
66
What are 2 ways blood can get into the lungs in TOF?
1. left to right shunt through a PDA
| 2. though the stenotic pulmonary valve
67
a sudden onset, life threatening hypoxic spell in patients with tetralogy of Fallot
Tet spell
68
What causes a Tet spell?
1. infundibular spasm
| 2. increase in right to left shunting of blood
69
What are 2 causes of a Tet spell?
1. sympathetic stimulation/ crying/ anxiety
- Tachycardia and increased contractility worsen infundibular spasm and subsequent right to left shunt
- Hyperventilation (with spontaneous ventilation) decreases intrathoracic pressure, which increases venous return, which increases right to left shunt
2. hypovolemia
- An underfilled heart decreases the diameter of the right ventricular outflow tract (RVOT)
70
What are 6 treatments for a Tet spell?
1. 100% oxygen and moderate hyperventilation
2. ketamine or phenylephrine to increase SVR
3. give fluid bolus to enhance preload
4. place the child in knee-chest position (increases SVR by reducing blood flow to lower extremities)
- valsalva maneuver
5. beta blocker (esmolol)
- tachycardia can worsen infundibular spasm
6. avoid beta agonists when trying to raise blood pressure
71
Anesthetic management of TOF? (7)
1. PDA should be kept open
2. increase SVR and decrease PVR to limit right to left shunting
3. avoid hypotension on induction
4. phenylephrine to control SVR
5. minimize sympathetic stimulation to cause infundibular spasm (ketamine dart before IV placement)
6. avoid air bubbles in IV line
7. preload should be elevated/ maintained
72
What is the best induction method for patients with TOF/
Use IV ketamine and AVOID mask induction with sevoflurane
| - avoid decreases in SVR
73
What is the palliative procedure patients will receive with TOF?
BT shunt
74
What is the final surgery patients with TOF will receive?
replacement of the pulmonic valve and closure of the VSD
75
defect where the right ventricle pumps into the aorta, while the left ventricle pumps to the pulmonary artery
transposition of the great arteries
76
What two shunts need to be present in transposition of the great arteries?
1. at least one right to left shunt
| 2. at least one left to right shunt
77
in transposition of the great arteries, a right to left shunt will shunt blood towards the _____
lungs
78
in transposition of the great arteries, a left to right shunt will shunt blood towards the ____
aorta
79
5 problems with transposition of the great arteries?
1. blood flow?
2. patient is perfused with what blood?
3. What is the most catastrophic in this abnormality?
4. onset time for inhalational anesthetics?
5. IV drugs?
1. blood flow to the lungs is decreased (only gets blood through VSD)
2. mixed venous arterial blood= low SpO2= compensating polycythemia
3. air bubbles in the IV line
4. slower
5. more potent
80
Management of transposition of the great arteries (7)
1. Keep the PDA open with PGE1
2. favor pulmonary blood flow and increase right to left shunting (increase SVR and decrease PVR)
3. IV induction is preferred over inhalational induction
4. doses and rates of IV drugs may need to be reduced
5. TIVA is preferred
6. avoid air bubbles in the IV lines
81
cardiac abnormality where the pulmonary veins empty into the right atrium instead of the left atrium
Total Anomalous Pulmonary Venous Return (TAPVR)
82
What cardiac defect do patients with total anomalous pulmonary venous return have?
ASD
-allows right to left shunting of the mixed venous/arterial blood so it can be pumped to the left side of the heart and out the aorta
83
What are the 4 problems with total anomalous pulmonary venous return?
1. pulmonary congestion
2. patient is perfused with mixed venous/arterial blood
3. left ventricle may struggle to provide adequate cardiac output post-op
4. prone to postoperative pulmonary hypertension
84
Management of total anomalous pulmonary venous return (3)
1. limit pulmonary blood flow (increase right to left shunting)
2. post-op inotropes to prevent low cardiac output and pulmonary hypertension
3. Post op: lower PVR (increased risk of pulmonary hyptertension)
85
What is a great drug of choice to lower PVR in patients with total anomalous pulmonary venous return post-op?
nitrous oxide
| -selectively lower pulmonary artery pressure PAP without lowering systemic blood pressure
86
abnormality where the patient has severely underdeveloped left heart structures that are incapable of pumping blood to the body
Hypoplastic left heart syndrome
87
What 3 issues does hypoplastic left heart syndrome have?
1. weak left ventricle
2. very small or closed mitral/ aortic valves
3. stenotic ascending aorta
88
What 2 defects does hypoplastic left heart syndrome have to have?
1. ASD
| 2. PDA
89
in hypoplastic left heart syndrome, anytime pulmonary blood flow is increased, cardiac output will (increase/ decrease)?
decrease
90
in hypoplastic left heart syndrome, anytime pulmonary blood flow is decreased, cardiac output will (increase/decrease)?
increase
91
in hypoplastic left heart syndrome, if an anesthetist lowers the PVR, they will _____ cardiac output
decrease
92
What are the 4 problems with hypoplastic left heart syndrome?
1. right ventricle is overworked
2. too much pulmonary blood flow
3. severely reduced cardiac output
4. perfused with mixed venous/arterial blood
93
Management of Hypoplastic left heart syndrome (2)
1. keep the PDA open with PGE1
| 2. increase PVR ( limit pulmonary blood flow)
94
What 2 things happen in the Norwood procedure for hypoplastic left heart syndrome?
1. right ventricle is attached to the aorta
- improves cardiac output
- no blood flow to lungs
2. BT shunt is placed
- how patient receives pulmonary blood flow
- blood flows left to right from brachiocephalic artery to pulmonary artery
95
What two things are done in the Hemi-fontan procedure for hypoplastic left heart syndrome?
1. SVC is attached to the pulmonary artery
- reduces strain on right ventricle
2. BT shunt is removed
96
What is the Fontan procedure and when does it take place?
The IVC is connected to the pulmonary artery after 2-3 years
97
After the Fontan procedure for hypoplastic left heart syndrome, what 3 ways does blood flow?
1. venous return bypasses right side and goes to pulmonary artery (right ventricle only receives blood from left atria)
2. all blood flow to the lungs is passive
3. the right ventricle now just pumps arterial blood to the rest of the body
98
Management for patients with Fontan physiology (3)
1. maintain preload and avoid increases in PVR
- blood flow to lungs is passive
2. spontaneous ventilation is preferred
3. invasive central and arterial monitoring is mandatory
99
the tricuspid valve is more or less blocked
tricuspid atresia
100
What cardiac defects do patients with tricuspid atresia HAVE to have?
BOTH and ASD and VSD
101
What are the 4 problems with tricuspid atresia?
1. severely underdeveloped right ventricle
2. left ventricle is overworked
3. the patient is perfused with mixed venous/arterial blood
4. the patient will either have too much or too little pulmonary blood flow (depending on size of the VSD and if there is pulmonic stenosis)
102
in tricuspid atresia, which ventricle does all the work?
left ventricle
103
in hypoplastic left heart syndrome, which ventricle does all the work?
right ventricle
104
in tricuspid atresia, and increase in PVR will _____ pulmonary blood flow and _____ cardiac output
decrease
| increase
105
in tricuspid atresia, the ____ can be large or small with the presence of pulmonary stenosis or not
VSD
106
In tricuspid atresia, if the VSD is large and there is no pulmonary stenosis present, where will blood shunt?
blood will shunt more left to right towards the lungs and pulmonary blood flow will be excessive
107
What is the management of tricuspid atresia dependent on?
how much blood flow the lungs are receiving
108
in tricuspid atresia, if pulmonary blood flow is limited, what is the patient's surgical option?
to receive a BT shunt
109
in tricuspid atresia, if the patient has increased pulmonary blood flow, what is the patient's surgical option?
they can receive a palliative band around the pulmonary artery
110
in tricuspid atresia, since the left ventricle is overworked and the patient is receiving mixed venous/arterial blood, What surgical procedure do these patients receive?
Fontan procedure
111
defect where the pulmonary valve is more or less blocked
pulmonary atresia
112
What two cardiac defects do patients with pulmonary atresia HAVE to have?
1. an ASD/ VSD
- way for blood to get from the right side of the heart to the left side of the heart
2. a PDA
- a way for blood to get into the lungs
113
What are the 3 problems with pulmonary atresia?
1. blood flow to the lungs is limited
- through the PDA
2. patient is perfused with mixed venous/arterial blood
3. these patients have signs of CHF and require inotropic support
114
What is the management of pulmonary atresia? (3)
1. keep the PDA open with PGE1
2. increase SVR and decrease PVR to promote pulmonary blood flow
3. inotropes if CHF is present
115
the aorta and pulmonary artery arise from same trunk, and this trunk is just like an “overriding aorta” in the sense that it sits above a VSD and is supplied by BOTH the right and left ventricles
truncus arteriosus
116
What are the 4 problems with truncus arteriosus?
1. left to right shunt exists= increased pulmonary blood flow
2. right to left shunt exists= hypoxia
3. body is perfused with mixed venous/arterial blood
4. pulmonary blood flow will be excessive
117
What is the management of truncus arteriosus?
1. have an appropriate PVR to SVR ratio
| 2. pulmonary congestion may be present and will need to limit blood flow to the lungs
118
An atrioventricular canal defect occurs when the patient has what 3 defects?
1. ASD
2. VSD
3. One atrioventricular valve in the middle of the heart, above the interventricular septum
This defect is also known as:
1. Endocardial Cushion Defect
2. Common atrioventricular canal (CAVC)
3. Septal defect
119
What are the 3 problems with atrioventricular canal defect?
1. , left to right shunting is more prominent and the patient will have excessive pulmonary blood flow
- however both shunting exists
2. patient is perfused with mixed venous/arterial blood
3. the ventricles will be volume overloaded leading to symptoms of CHF
120
What is the management for atrioventricular canal defect?
1. limit pulmonary blood flow
| 2. inotropic support
121
defect where the right ventricle supplies both the pulmonary artery AND the aorta
double outlet right ventricle
122
What cardiac defect is a patient also born with in double outlet right ventricle?
a VSD
| -allows oxygenated blood to get to the right side of the heart so it can get pumped out to the body
123
What may or may not be present in patients with double outlet right ventricle?
pulmonic stenosis
- If pulmonary stenosis isn’t present, the majority of the blood will go to the lungs and the patient will probably have excessive pulmonary blood flow
- If pulmonary stenosis is present, the patient probably won’t have excessive blood flow
124
What are 2 problems with double outlet right ventricle?
1. right ventricle is overworked
| 2. patient is perfused with mixed venous/arterial blood
125
What is the management of double outlet right ventricle?
Depends on how much pulmonary blood flow there is
126
an abnormal development of the aortic arch that encircles the trachea and/or esophagus
vascular rings
it can lead to:
1. Tracheal compression
2. Dyspnea
3. Dysphagia
127
What is another name for vascular rings?
double aortic arch
128
Anesthetic management for vascular rings:
1. what type of surgery?
2. ETT?
3. extubation?
4. What type of ventilation/induction?
1. thoracotomy
2. smaller size ETT, possible armored
3. Extubation may be considered if tracheomalacia or stenosis is not anticipated
4. inhalational induction with spontaneous ventilation
129
the heart is on the right side of the body (instead of the left)
dextrocardia
130
dextrocardia where patients have a reversal of the normal positions of the abdominal organs, in addition to the heart
situs inversus
- most common
- less comorbidities
131
dextrocardia where patients have normally positioned abdominal organs
situs solitis
- less common
- more comorbidities
132
If a patient has ductal dependent systemic blood flow, it means that a _____ is required in order for adequate systemic blood flow to occur
PDA
| -blood flow to the extremities is coming from RIGHT side of the heart through a PDA
133
In order for patients to have ductal dependent systemic blood flow, they need to have _______
What 2 heart defects does this include?
left ventricular outflow obstruction
1. hypoplastic left heart syndrome
2. interrupted aortic arch
134
What are 2 symptoms that patients with ductal dependent systemic blood flow have?
1. CHF and pulmonary edema
| 2. Higher preductal blood pressure & SaO2
135
If a patient has ductal dependent pulmonary blood flow, it means that a ______ is required in order for adequate pulmonary blood flow to occur
PDA
-blood flow to the lungs is coming from the LEFT side of the heart through a PDA (and blood is shunting LEFT TO RIGHT across the PDA, just like it normally does after birth)
136
in order for patients to have ductal dependent pulmonary blood flow, they need to have ______
What 2 heart defects does this include?
right ventricular outflow obstruction
1. TOF
2. Pulmonary atresia
