Transcript Congenital Heart Disease

Congenital Heart Disease
Greg Gordon MD
Updated 2012 Version
Training for Career in
Pediatric Cardiac Anesthesia
Specific Fellowship: Rare
Suggested training (US & UK):
•Pediatric Anesthesia: 12 months
•Adult Cardiac Anesthesia: 6 months
•Pediatric Cardiac Anesthesia: 6 months
•Pediatric Critical Care: 6 months
Baum V & De Souza DG. Pediatric Anesthesia 17:407, 2007
White MC & Murphy TWG. Pediatric Anesthesia 17:421, 2007
• PDA ligations
• Murmurs preop
• CHD patients for
noncardiac surgery
Adults with CHD in US today
2,140,000
Growing 5% per year
Cahalan MK. Anesthetic Management of Patients with Heart Disease.
IARS 2003 Review Course Lectures
3 y/o with TOF
s/p right BTS
For dental restorations
•Turns blue with crying
•Scheduled to undergo cardiac repair
in 3 months
•SpO2 93
•Systolic ejection murmur
•Slight clubbing of fingers
•Hct 52
Tammy
(Recent oral board case)
5 y/o for T&A
Systolic murmur
• VSD
• Needs surgical closure
• Cardiologist recommended T&A first
Victor
11 y/o with tricuspid atresia
s/p Fontan procedure
For scoliosis repair
•Temporary BTS at age 3 weeks
•Modified Fontan at age 3 years
•Meds: digoxin, captopril
•SpO2 88 on RA, 98 in O2
•P 67, BP 99/42
•First degree AV block
Fran
Objectives
Participants will be able to more intelligently discuss:
• Newborn heart and lungs
• Initial evaluation the child’s heart
• Pathophysiology of selected CHDs
• Anesthetic implications of CHD
The Newborn Heart
CHOP “Duct Busters”
Provide service to 17 area NICUs
Send team of 2 each
surgeons
anesthesia providers
(attending + CRNA)
nurses
Operate within 24 - 48 hours
Monday – Friday
No weekends
Reimbursement
exceeds other cardiac services
Susan Nicholson and Gould DS et al: Pediatrics 2003 112:1298-1301
The Newborn Heart
Foramen Ovale
Functional closure first hours as LAP > RAP
Probe-patent
50% of 5-year-olds
25% of 20-year-olds
Paradoxical embolus
The Newborn Heart
Ventricular tissue
•Fewer myocytes
•Greater proportion of connective tissue
•Relative RVH
So:
•Decreased compliance
•More sensitive to preload
The Newborn Heart
•Near peak of Starling curve
•Stroke volume relatively fixed
Normally near peak of Starling curve
•C.O. relatively
heart
rate dependent
Stroke volume
relatively
fixed
C.O. relatively heart rate dependent
The Newborn Heart
++
Newborn myocardium derives relatively
high fraction of activator Ca from the
extracellular pool, so
Beware Ca channel blockers
The Preterm Infant Heart
More sensitive to depressant effects of inhaled agents
Decreased response to catecholamines
Relatively high PVR persists
Pulmonary vasculature more sensitive to vasoconstriction by:
Hypoxia
Acidosis
Hypercarbia
CHD Pearl
murmur in newborn =
benign disease
Initial evaluation of child’s heart
History:
To determine
•Level of function
•CHF
Initial evaluation of child’s heart
History - cyanosis
•Turn blue?
•At rest?
•When crying?
•Passes out?
•Stops playing and squats
Initial evaluation of child’s heart
History - CHF
Run around like crazy?
Like sibs?
Or tends to be quiet, slow?
Infant – feeding behavior:
Slow to finish bottle?
Sweats when nursing?
Eyes puffy in the morning?
Initial evaluation of child’s heart
Physical exam
•Listen to heart first when/if infant quiet
(warm stethoscope)
•First concentrate on S1 and especially S2
Louder than normal?
Split normally?
•Systolic murmur:
Starts after or obscures S1?
•Diastolic murmur?
•Widely radiating murmur?
•Palpate liver
•BP in arm and leg
•Tongue - cyanosis
CHD Pearl
Sudden CHF in ‘healthy’ 10-day-old =
complicated coarct
General Approach to CHD Patient
1. Define cardiovascular pathology
2. Predict pathophysiology
3. Determine hemodynamic goals
4. Anticipate emergency treatments
Cahalan MK. Anesthetic Management of Patients with Heart Disease.
IARS 2003 Review Course Lectures
Don’t worry
Almost any anesthetic technic
may be used in any CHD patient
if
the anesthesiologist understands
•the pathophysiology of the lesion and
•the pharmacology of the drugs employed.
Normal Neonate
SVC
RA
m=2
1 week
60
PV
99
LA
m=4
65
RV
LV
30/3
MPA
30/12 m=18
65
65
80/5
99
99
Ao
80/50
Some basic definitions
physiologic
L to R shunt =
lungs to lungs shunt
Blood that is returning to the heart
from the lungs is recirculated back
to the lungs without going out to the
rest of the body.
Some basic definitions
physiologic
R to L shunt =
body to body shunt
Blood that is returning to the heart
from the body is recirculated directly
back to the body without going to the
lungs to be oxygenated.
Some basic definitions
effective pulmonary
blood flow=
body to lungs flow
Blood that is returning to the heart
from the body that is actually directed
to the lungs to be oxygenated.
Some basic definitions
Nonrestrictive VSD
VSD large enough that
pressure equalizes in the two ventricles
(no pressure gradient can be maintained)
LV pressure = RV pressure
Premature
1 week old
28 weeks EGA
SVC
RA
PV
LA
96
65
RV
LV
65/10
65/12
65
MPA
65/30
96
Ao
PDA
80
92
65/25
to R arm
& head
To L arm
MHMC PDA ligation
CHD Pearl
blue newborn +
no airway or breathing problem +
quiet heart =
decreased PBF lesion (TOF)
Tetralogy Of Fallot
Most common cyanotic lesion
NB: cyanosis plus quiet heart
Diminished pulmonary blood flow
Ao ejection click
Hypercyanotic “tet” spells
tachypnea, pallor, LOC, less murmur
Tammy
3 y/o with TOF s/p right BTS
1. Define cardiovascular pathology
2. Predict pathophysiology
3. Determine hemodynamic goals
4. Anticipate emergency treatments
Tammy
Tetralogy Of Fallot
Essentially a duality:
1. severe RVOT obstruction plus
2. nonrestrictive VSD
With anatomic consequences:
1. RVH
2. Overriding aorta
And physiologic consequences
1. R to L shunt
2. Diminished pulmonary blood flow
Tammy
Tetralogy of Fallot
SVC
40
96
RA
LA
RV
LV
m=5
m=4
85/6
MPA
15/10
40
40
85/5
85
50
Ao
85/45
Tetralogy Of Fallot
s/p
right BTS?
Blalock-Taussig Shunt
Tammy
Thomas-Blalock-Taussig Shunt
Vivien Thomas
Alfred Blalock
Helen Taussig
Vivien Thomas, Partners of the Heart, 1998 and
Something the Lord Made - Best Made-for-TV Movie, 2004
November 29, 1944
Thomas-Blalock-Tuassig
Dr. Blalock does the Blalock
(Johns Hopkins)
Systemic to Pulmonary Shunts
Tetralogy Of Fallot
Maintain adequate tissue oxygenation
1. Avoid increasing O2 demand
2.Maintain SVR, systemic BP
3.Minimize PVR
Avoid dehydration,
especially if polycythemic
Oral premed/induction
midazolam + ketamine
Tammy
Free written board answer:
Speed of induction:
R->L shunt
• Inhalational: slower
• IV: faster
L->R shunt
• Inhalational: maybe faster
• IV: slower
But probably not clinically important
Tanner et al. Anesth Analg 64:101, 1985
Beware:
blunted chemoreceptor response to
Tammy
hypoxemia
Beware:
VD:VT may be 0.6
Tammy
And increase with
•start of mechanical ventilation
•too much PEEP
•hypovolemia
ETCO2 << PaCO2
Tetralogy Of Fallot
Minimize R->L Shunt
MAINTAIN
SVR
•ketamine
•phenylephrine
Tammy
Tetralogy Of Fallot
Minimize RVOT obst & PVR
•oxygen
•beta blocker ready
Maybe:
•nitroglycerin
•phentolamine
•tolazoline
•prostaglandin E1
•nitric oxide
Tammy
Tetralogy Of Fallot
And of course:
•No Air in lines
Maybe no N2O
and
infective
endocarditis
prophylaxis
Tammy
Infective Endocarditis Prophylaxis
Infective endocarditis prophylaxis
for dental procedures is reasonable
only for patients with underlying
cardiac conditions associated with
the highest risk of adverse outcome
from infective endocarditis.
Wilson W, Taubert KA et al. AHA Guidelines. Prevention of
Infective Endocarditis. Circulation 116:1736-54, 2007
Infective Endocarditis Prophylaxis
Recommended
Unrepaired cyanotic CHD,
including palliative
shunts and conduits.
Circulation 116:1736, 2007
Infective Endocarditis Prophylaxis
Recommended
CHD completely repaired with
prosthetic material or device
less than 6 months ago.
Circulation 116:1736, 2007
Infective Endocarditis Prophylaxis
Recommended
Repaired CHD with
residual defect(s) at or near
a prosthetic patch or device.
Circulation 116:1736, 2007
Infective Endocarditis Prophylaxis
Recommended
Prosthetic material in a valve.
Previous infective endocarditis.
Valvulopathy after transplant.
Circulation 116:1736, 2007
Infective Endocarditis Prophylaxis
Recommended
For patients with the above conditions,
prophylaxis is reasonable for
all dental procedures that involve
manipulation of gingival tissue or
the apical region of teeth or
perforation of the oral mucosa.
Wilson W, Taubert KA et al. AHA Guidelines. Prevention of Infective Endocarditis.
Circulation 116:1736-54, 2007
Infectious Endocarditis Prophylaxis
NOT Recommended
Any form of CHD not listed above
Local injection -> noninfected tissue
Shedding deciduous teeth
Bleeding/trauma to lips, oral mucosa
Circulation 116:1736, 2007
Tetralogy Of Fallot
infective endocarditis prophylaxis
and
maintain
SVR
Tammy
Tetralogy Of Fallot
Treatment of Tet Spell
•Knee-chest position
•O2
•Morphine 0.1-0.2 mg/kg IM,IV
•Phenylephrine gtts : increase systolic BP 20-40 mmHg
•Beta blockade, e.g. propanolol: titrate to 0.1 mg/kg
•ABG: NaHCO3 if necessary
•Surgery
CHD Pearl
blue newborn +
no airway or breathing problem +
hyperactive heart =
TGA
(Recent oral board case)
5 y/o for T&A
Systolic murmur
• VSD
• Needs surgical closure
• Cardiologist recommended T&A first
Victor
Newborn VSD
Most common lesion
2/3rds close spontaneously
Small VSD
Definite murmur
Will probably close
Large VSD
No murmur
No problems
Home with Mom
CHF symptoms by 4-8 weeks
VSD
nonrestrictive
SVC
98
60
96
RA
m=6
90/8
90/35
m=12
80
RV
MPA
LA
LV
90/10
94
88
94
Ao
90/60
Nonrestrictive VSD
L->R shunt
Pulmonary to System Flow Ratio
QP:QS =
SaO
2 – SvO2
__________
SpvO2 – SpaO2
=
94 - 60
_______
98 - 88
=
3.4:1
Victor
Nonrestrictive VSD
Besides, of course:
•No Air in lines
Maybe no N2O
and
infectious
endocarditis
prophylaxis
Victor
Proper management of the physiologic
abnormalities is more important
than the choice of specific anesthetic
and pharmacologic approaches.
Nonrestrictive VSD
Maintain PVR
Normal ventilation
(paCO2 = 40’s)
FIO2 < 1
Lower SVR better
Major inhalational agents
Thiopental, propofol
Victor
11 y/o with tricuspid atresia
s/p Fontan procedure
For scoliosis repair
•Temporary BTS at age 3 weeks
•Modified Fontan at age 3 years
•Meds: digoxin, captopril
•SpO2 88 on RA, 98 in O2
•P 67, BP 99/42
•First degree AV block
Fran
Tricuspid Atresia
3rd most common cyanotic CHD
1. TOF
2. TGA
Type IB most common
•Small VSD (and RV)
•PS
20% extracardiac abnormalities
•GI
•Musculoskeletal
Cyanosis
•Mixing in LA
•Decreased PBF
•Spells
Fran
Modified
Bidirectional
Modified
Age 5 years
16/10
16/12
88/6
11 y/o with tricuspid atresia s/p Fontan procedure
Potential problems during scoliosis repair
Hypoxemia
1. Hypovolemia
2. Low PBF
CHF
1. Volume shifts
2. Anemia
3. Hypertension
Paradoxical embolus
Thrombosis
Vena cavae
RA
Pulmonary arteries
Fran
11 y/o with tricuspid atresia s/p Fontan procedure
Goals during scoliosis repair
Monitor RA pressure
•RA catheter
•Maintain starting pressure
Maintain systemic BP near baseline
Minimize myocardial depressants
NO AIR IN LINES
No N2O
Relatively high FIO2
Normal Hct
Fran
Age 5 years
16/10
16/12
88/6
For more cool stuff about CHD
check out the lesson and fun Quiz at
http://greggordon.org/edu/ped/chd1.htm
Now we can more intelligently discuss:
• Newborn heart and lungs
• Initial evaluation the child’s heart
• Pathophysiology of selected CHD
• Anesthetic implications of CHD