Congenital Heart Disease
description
Transcript of Congenital Heart Disease
Congenital Heart DiseaseGreg Gordon MD
American Society of Dentist Anesthesiologists Baltimore, MD, May 3, 2012
Training for Career in Pediatric Cardiac Anesthesia
Suggested training (US & UK):
Specific Fellowship: Rare
• 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, 2007White MC & Murphy TWG. Pediatric Anesthesia 17:421, 2007
?Children & adults scheduled
for dental or oral surgery
and known to have CHD
Preop heart murmur:
Is it CHD?
Adults with CHD in US today
1,500,000Growing 2% per year
Cahalan MK. Anesthetic Management of Patients with Heart Disease. IARS 2003 Review Course LecturesAndropolous, D. Anesthesia for the Patient with Congenital Heart DiseaseFor Noncardiac Surgery. ASA Refresher Course Lectures 2011
Tammy
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
5 year-old for dental work
Systolic murmur
Victor
VSD
Needs surgical closure
Cardiologist recommended dental restorations first
Fran
11 y/o with tricuspid atresia
s/p Fontan procedure
•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
For lengthy oral surgery with possible large blood loss
26 y/o with D-TGA
s/p Mustard in infancy
Dental restorations
Developmental delay
Pacemaker
Travis
4 y/o D-TGA
s/p Jatene in infancy
Dental restorations
Very active
Keeps up with peers
Never any cyanosis
Tracy
Objectives
Participants will be able to more intelligently discuss:
• Newborn and infant heart and
lungs
• Initial evaluation the child’s heart
• Pathophysiology of selected CHDs
• Anesthetic implications of CHD
Pediatric AnesthesiaCongenital Heart Disease
LessonPresentationQuiz
greggordon.org
Fetal Circulation
Placenta (oxygenation) ->Umbilical vein ->Ductus venosus (liver bypass) –>IVC ->Foramen ovale (RV bypass) ->Left atruim ->Left ventricle –>Ascending aorta (brain) ->SVC ->Right atrium ->Right ventricle ->Main pulmonary artery ->Ductus arteriosus (lung bypass) ->Descending aorta ->Placenta
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
The Newborn Heart
Ventricular tissue
•Fewer myocytes
•Greater proportion of connective tissue
•Relative RVHSo:
•Decreased compliance
•More sensitive to preload
The Newborn Heart
Normally near peak of Starling curveStroke volume relatively fixedC.O. relatively heart rate dependent
•Near peak of Starling curve
•Stroke volume relatively fixed
•C.O. relatively heart rate dependent
Ca+
+
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 agentsDecreased 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
1.Well compensated with
no limitations
2. Some limitations
3. Poorly compensated with
severe limitations
CHF and/or cyanosis
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
Recent Cardiologist Evaluation Needed?
Completely corrected,
Well compensated and stable:
Probably not
Complex and/or poorly compensated;
Cyanotic and/or single ventricle:
YES: Evaluation & ECHO within 3-6 mos
Don’t worry
Almost any anesthetic technicmay be used in any CHD patient
if
the anesthesiologist understands
•the pathophysiology of the lesion and
•the pharmacology of the drugs employed.
Normal Neonate
1 week SVC
RA
RV
MPA
PV
LA
LV
Ao
m=2
30/3
30/12 m=18
m=4
80/5
80/50
60
65
65
65
99
99
99
Some basic definitions
physiologicL 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
physiologicR 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 pulmonaryblood 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
SVC
RA
RV
MPA
PV
LA
LV
AoPDA
Premature1 week old
28 weeks EGA
65/2565/30
65/1265/10
96
96
92
65
65
80
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)
Tammy
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
1.Define cardiovascular pathology
2.Predict pathophysiology
3.Determine hemodynamic goals
4.Anticipate emergency treatments
3 y/o with TOF s/p right BTS
Tammy
Tetralogy Of Fallot
Essentially a duality:1. severe RVOT obstruction plus2. nonrestrictive VSD
With anatomic consequences:1.RVH2.Overriding aorta
And physiologic consequences1.R to L shunt2.Diminished pulmonary blood flow
Tetralogy of Fallot
SVC
RA
RV
MPA
LA
LV
Ao
40
40
40
96
85
50
m=5
85/6
15/10
m=4
85/5
85/45
Tammy
Tetralogy Of Fallot
s/p right BTS?
Blalock-Taussig Shunt
Thomas-Blalock-Taussig Shunt
Vivien Thomas, Partners of the Heart, 1998 andSomething the Lord Made - Best Made-for-TV Movie, 2004
Helen Taussig
Alfred Blalock
Vivien Thomas
Thomas-Blalock-Tuassig
Dr. Blalock does the Blalock(Johns Hopkins)
Systemic to Pulmonary Shunts
Tammy
Tetralogy Of Fallot - Goals
Maintain good hydration, especially if polycythemic
Maintain adequate tissue oxygenation
1.Avoid increasing O2 demand2.Maintain SVR, systemic BP3.Minimize PVR
Oral premed/inductionmidazolam + ketamine(0.6 mg/kg + 6 mg/kg)
Tetralogy Of Fallot - Goals
Minimize PVR
Oxygen to FIO2 = 1
Mild hyperventilation
PaCO2 low 30’s
pH 7.45
Adequate anesthesia
Adequate analgesia
Normothermia, warm
Nitric oxide
Tammy
Tetralogy Of Fallot - Goals
Maintain SVR
Intravascular volume
Well hydrated
IV bolus prn
Maintain BP
ketamine
phenylephrine
Tammy
Free written board answer:
Speed of induction:
R->L shunt• Inhalational: slower• IV: faster
L->R shunt• Inhalational: maybe faster• IV: slowerBut probably not clinically important
Tanner et al. Anesth Analg 64:101, 1985
Beware:
blunted chemoreceptor response to
hypoxemiaTammy
Beware:
Tammy
VD:VT may be 0.6And increase with•start of mechanical ventilation•too much PEEP•hypovolemia
ETCO2 << PaCO2
VD/VT = (PaCO2 – ETCO2)/PaCO2
Tammy
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
infective endocarditis prophylaxis
and
Maybe no N2O
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
Circulation 116:1736, 2007
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.
Infectious Endocarditis Prophylaxis
Circulation 116:1736, 2007
NOT Recommended
Any form of CHD not listed above
Local injection -> noninfected tissue
Shedding deciduous teeth
Bleeding/trauma to lips, oral mucosa
Tammy
Tetralogy Of Fallot
and
SVRmaintain
infective endocarditis prophylaxis
Tetralogy Of Fallot
Treatment of Tet Spell
• 100% O2
• knee-chest position
• morphine 0.05-0.1 mg/kg
• crystalloid 15-30 ml/kg
• phenylephrine to increase systolic BP 20-40
mmHg
• beta blockade: propranolol 0.1 mg/kg or
esmolol 0.5 mg/kg and 50-300 mcg/kg/min
• ABG: NaHCO3 if necessary
• ECMO/surgery DiNardo JA et al. in Davis PJ et al. Smith’s Anesthesia for Infants and Children, 8th ed. 2011
Schedule case early in the day
•Less fasting dehydration
•Less time of stress
•More time to monitor postop
•More support available
•Less team turnover
Schedule case WHERE?
•Well-compensated, no limitations, not-complex:
Ambulatory center may be OK
•Not well-compensated, complex:
Center with CHD expertise & backup available
5 year-old for dental work
Systolic murmur
VSD
Needs surgical closure
Cardiologist recommended dental restorations
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
SVC
RA
RV
MPA
LA
LV
Ao
m=6
90/8
90/35
m=12
90/10
90/60
60
80
88
96
94
94
nonrestrictive
98
Nonrestrictive VSD
L->R shunt
Pulmonary to System Flow Ratio
QP:QS = SaO2 – SvO2__________
SpvO2 – SpaO2
=94 - 60_______98 - 88
= 3.4:1
Victor
Nonrestrictive VSD - Goals
Maintain PVR
Lower SVR better
Normal ventilation(paCO2 = 40’s)
FIO2 < 1
Major inhalational agents
Propofol, thiopental
Victor
Proper management of the physiologic
abnormalities is more important
than the choice of specific anesthetic
and pharmacologic approaches.
Nonrestrictive VSD - Goals
Of course:
•No Air in linesMaybe no N2O
infective endocarditis prophylaxis?
NO longer recommended
Wilson W, Taubert KA et al. AHA Guidelines. Prevention of Infective Endocarditis. Circulation 116:1736-54, 2007
Victor
Unrepaired nonrestrictive VSD ->
1. PVOD developing 2. Less L->R shunt3. Less CHF4. Less murmur5. PVOD irreversible6. R-L shunt7. Less PBF8. More cyanosis
Eisenmenger syndrome
Victor
Fran
11 y/o with tricuspid atresia
s/p Fontan procedure
•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
Oral surgery, big blood loss?
Fran
Tricuspid Atresia3rd most common cyanotic CHD1. TOF2. TGA
20% extracardiac abnormalities•GI•Musculoskeletal
Cyanosis•Mixing in LA•Decreased PBF•Spells
Type IB most common•Small VSD (and RV)•PS
Fontan procedure
Indicated to palliate:
Tricuspid atresia
Hypoplastic left heart syndrome
Double outlet right ventricle
Double inlet left ventricle
Unbalanced AV septal defect
Fontan physiology
Two defining features:
1. Single systemic ventricle
2. Pulmonary blood flow:
without pump!
Fontan procedure
Three main versionsAtriopulmonary connection (the original)Total cavopulmonary connection (TCPC):
Intracardiac (lateral tunnel)Extracardiac
Two stages:Bidirectional Glenn shuntFontan completion
ModifiedBidirectional
Modified
Collaborate with cardiologist
Clarify
History
Pathophysiology
Risks
Status best possible?
Explain recent studies
16/10
16/1288/6
Age 5 years
Fran
11 y/o with tricuspid atresia s/p Fontan procedure
Potential problems during surgery
CHF1. Volume shifts2. Anemia3. Hypertension
Paradoxical embolus
Thrombosis Vena cavae RA Pulmonary arteries
Hypoxemia1. Hypovolemia2. Low PBF
Fran
11 y/o with tricuspid atresia s/p Fontan procedure
Goals during surgery
Monitor RA pressure•RA catheter•Maintain starting pressure
Maintain systemic BP near baseline
Minimize myocardial depressants
NO AIR IN LINESNo N2O
Relatively high FIO2
Normal Hct
IE prophylaxis
Fran
11 y/o with tricuspid atresia s/p Fontan procedure
MAJOR GOAL
Maintain cardiac output and
transpulmonary gradient (TPG):
Adequate preload
Low PVR
Low intrathoracic pressure
Normal ventilation
Unobstructed PV return
Regular sinus rhythm
Low ventricular afterload
Normal ventricular funtion
16/10
16/1288/6
Fran
Monitor RA PressureRight IJ?
CHD Pearl
blue newborn +
no airway or breathing problem +
hyperactive heart =
TGA
26 y/o with D-TGA
s/p Mustard in infancy
Dental restorations
Developmental delay
Pacemaker
Travis
TGA s/p Mustard
D-TGA, Transposition of the Great Arteries
Newborn: 75% no VSD
PGE1 to keep PDA
BAS prior to surgery
Older: Mustard or Senning
Younger: Jatene ASO
Travis
SVC
RA
RV
LA
LV
Ao
MPA
D-TGA
PDA
99
99
BAS
65
D-TGAMustard Procedure
SVC
RV LV
Ao MPA
PV
95
D-TGA + Mustard
RV systemic ventricle
RV failure Tricuspid regurgitationVentricular arrhythmiasSudden death
Atrial injury/scarsAtrial flutter/fibSick sinus syndrome
Travis
26 y/o TGA s/p Mustard, pacemaker
Poor RV function
Consider inotrope
Arrhythmias
Pacemaker
CIED practice advisory
Travis
CIED practice advisory
Practice Advisory for the Perioperative Management of Patients with CardiacImplantable Electronic Devices: Pacemakers and Implantable Cardioverter-Defibrillators. Anesthesiology 114:247-61, 2011
Preop: What type CIED?Pacer dependent?Check function: interrogate device
EMI (e.g. Bovie) during procedure?Reprogram to asynchronous mode?Have backup pacing &
defibrillation equipmentimmediately available
4 y/o D-TGA
s/p Jatene in infancy
For dental restorations
Very active
Keeps up with peers
Never any cyanosis
Tracy
D-TGA
SVC
RA
RV
LA
LV
Ao
MPA
D-TGA
SVC
RA
RV
LA
LV
MPA Ao
4 y/o D-TGA s/p Jatene
Treat as normal, healthy child!
Be happy!
Tracy
For more cool stuff about CHDcheck out the lesson and fun Quiz at
http://greggordon.org/edu/ped/chd1.htm
Now we can more intelligently discuss:
•Newborn and infant heart and lungs
• Initial evaluation the child’s heart
• Pathophysiology of selected CHD
• Anesthetic implications of CHD