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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
Adults with CHD in US today
2,140,000Growing 5% per year
Cahalan MK. Anesthetic Management of Patients with Heart Disease. IARS 2003 Review Course Lectures
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
(Recent oral board case)
5 y/o for T&A
Systolic murmur
• VSD
• Needs surgical closure
• Cardiologist recommended T&A first
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
For scoliosis repair
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
CHOP “Duct Busters”
The Newborn Heart
Provide service to 17 area NICUsSend team of 2 each
surgeons anesthesia providers
(attending + CRNA)nurses
Operate within 24 - 48 hoursMonday – Friday No weekends
Reimbursement exceeds other cardiac
servicesSusan Nicholson and Gould DS et al: Pediatrics 2003 112:1298-1301
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
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
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
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
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
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
Tammy
Tetralogy Of Fallot
Avoid dehydration, especially if polycythemic
Maintain adequate tissue oxygenation
1.Avoid increasing O2 demand2.Maintain SVR, systemic BP3.Minimize PVR
Oral premed/inductionmidazolam + ketamine
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:
Tammy
VD:VT may be 0.6And increase with•start of mechanical ventilation•too much PEEP•hypovolemia
ETCO2 << PaCO2
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
Wilson W, Taubert KA et al. AHA Guidelines. Prevention of Infective Endocarditis. Circulation 116:1736-54, 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
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
(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
Nonrestrictive VSD
Victor
L->R shunt
Pulmonary to System Flow Ratio
QP:QS = SaO2 – SvO2__________
SpvO2 – SpaO2
=94 - 60_______98 - 88
= 3.4:1
Nonrestrictive VSD
Victor
Besides, of course:
•No Air in linesMaybe no N2O
and
infectious endocarditis prophylaxis
Proper management of the physiologic
abnormalities is more important
than the choice of specific anesthetic
and pharmacologic approaches.
Nonrestrictive VSD
Victor
Maintain PVR
Lower SVR better
Normal ventilation(paCO2 = 40’s)
FIO2 < 1
Major inhalational agents
Thiopental, propofol
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 scoliosis repair
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
Fran
11 y/o with tricuspid atresia s/p Fontan procedure
Potential problems during scoliosis repair
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 scoliosis repair
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
For more cool stuff about CHDcheck out the lesson and fun Quiz at
http://greggordon.org/edu/ped/chd1.htm
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