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Anesthesia and
the Sick Heart
Billy Corbett MD FAAP
Capitol Anesthesiology Association
Dell Children’s Medical Center
Talk Overview
n The “safety” of anesthesia
n Preoperative evaluation and risk stratification
n Induction of anesthesia: how to safely put a sick
heart to sleep
n Putting it all together
Morray JP. Cardiac arrest in anesthetized children. Pediatric Anesthesia 2011; 22: 722-729.
Anesthesia-Related Cardiac
Arrest
How Safe is Pediatric
Anesthesia?
n Incidence of cardiac arrest: 1.4-4.6:10,000 (3-
6X higher in children <1 year old, increased risk
for ASA physical status > III)
n Overall incidence of anesthesia-related death
1:10,000-1:40,000
Paterson N et al. Risk in pediatric anesthesia. Pediatric Anesthesia 2011; 21: 848-857.
van der Griend BF et al. Postoperative Mortality in Children After 101,885 Anesthetics at a Tertiary Pediatric
Hospital. Anesthesia & Analgesia 2011; 112: 1440-1447.
Odegard KC et al. The Frequency of Anesthesia-Related Cardiac Arrests in Patients with Congenital Heart
Disease Undergoing Cardiac Surgery. Anesthesia & Analgesia 2007; 105: 335-343.
Morray JP. Cardiac arrest in anesthetized children. Pediatric Anesthesia 2011; 22: 722-729.
American Society of Anesthesiologists
Physical Status
n ASA physical status
n 1. Normal healthy patient
n 2. Mild systemic disease
n 3. Severe systemic disease
n 4. Severe systemic disease that is constant threat to life
n 5. Moribund - not expected to survive the operation
n 6. Brain dead for organ donation
ASA Status and
Complications
Morray JP. Cardiac arrest in anesthetized children. Pediatric Anesthesia 2011; 22: 722-729.
n Retrospective chart review
n 129 patients with cardiomyopathy undergoing 236
anesthetics
n 4 cardiac arrests (in 2 patients)
n Fractional shortening <= 16% in both patients
n Many different combinations of induction drugs
with no ideal choice
n All successfully resuscitated
Take-Home Points
n 26 patients undergoing 34 general anesthetics
n Non-cardiac surgical
n 18 complications in 12 patients (38% complication
rate for 34 anesthetics)
n Stratified into 3 groups based on preoperative
shortening fraction
Echocardiographic Function
Function Shortening
Fraction Ejection Fraction
Normal > 28% >55-63%
Mild 23-28% >45%
Moderate 16-22% 20-45%
Severe <16% <20%
Dilated Cardiomyopathy
n 15 (83%) occurred in patients with severe
ventricular dysfunction
n Patients with shortening fraction < 16% are at the
highest risk for perioperative morbidity and
mortality
n 14 of 21 patients (67%) with severe ventricular
dysfunction observed in ICU postoperatively
n Importance of a multispecialty team approach to
caring for these patients
Take-Home Points
Cardiac Arrest in Children
with Cardiomyopathy
n Incidence of cardiac arrest after induction:
170:10,000 (40-120 times more likely than
with healthy patients)
n Patients with severe ventricular dysfunction at
the highest risk
Lynch J et al. Cardiac arrest upon induction of anesthesia in children with cardiomyopathy: an analysis of
incidence and risk factors. Pediatric Anesthesia 2011; 21: 951-957.
Kipps AK et al. Children with cardiomyopathy: complications after noncardiac procedures with general
anesthesia. Pediatric Anesthesia 2007; 17: 775-781.
Types of Cardiomyopathies
n Dilated (60%)
n Hypertrophic (30%)
n Restrictive (3%)
n Left Ventricular Noncompaction (rare)
Anesthetic Goals for
Hypertrophic Cardiomyopathy
n Dynamic left ventricular outflow tract
obstruction
n Maintain or increase afterload
n Ensure adequate volume loading
n Decrease heart rate
n Decrease contractility
Plan of Attack
n Beta blockade perioperatively often
n Establish good venous access
n Preinduction fluid bolus (10ml/kg)
n Avoid decreases in afterload: Etomidate or
Ketamine
Lake, C and Booker P. Pediatric Cardiac Anesthesia 4th ed. 2005: 530-535.
Anesthetic Goals for Dilated
Cardiomyopathy
n Avoid increases in SVR
n Maintain or augment contractility
n Appropriate volume load
n Plan for invasive monitors
n For most severe cases, consider ECMO
backup
Plan of Attack
n Continuation of preoperative inotropes
n Adequate premedication to facilitate placement
of good intravenous access +/- arterial
monitoring
n Gentle induction
n Ensure adequate anesthesia depth prior to
laryngoscopy to avoid sudden increases in SVR
Preinduction Questions?
n Does the child have intravenous access or can
it easily be obtained?
n Does the patient need preoperative anxiolysis?
n Intravenous or mask induction?
Premedication =
n Mode of delivery: intravenous, oral, nasal,
intramuscular
n Most commonly: midazolam 0.5-1 mg/kg po or
0.05-0.1 mg/kg iv
n Relieves anxiety and provides amnesia
The Art of Induction
n The ideal induction agent
n Preserve hemodynamic stability
n Minimal depression of contractility
n Maintain relationship between pulmonary
and systemic vascular resistances
Surgur Z et al. Comparison of sevoflurane and ketamine for anesthetic induction in children with congenital
heart disease. Pediatric Anesthesia 2008; 18: 715-721.
silver bullet: a straightforward
solution perceived to have
extreme effectiveness
Anesthesia Induction Drugs
HR CO Contractility SVR PVR/SVR
Sevofluran
e
Propofol
Ketamine
Etomidate
Fentanyl-
Midazolam
Sevoflurane
n Sweet smelling anesthetic gas
n Predominant hemodynamic effect is decrease
in SVR, leading to decreased arterial pressure
n PVR:SVR maintained
n Single ventricle with stable ventricular
function no decrease in myocardial
performance index
Rosenthal DN et al. Heart failure in children: anesthetic implications. Pediatric Anesthesia 2011; 21: 577-
584.
Williams GD. The Hemodynamic Effects of Propofol in Children with Congenital Heart Disease.
Anesthesia & Analgesia 1999; 89: 1411-1416.
n “Milk of amnesia”
n Decreases preload (dilates venous capacitance
vessels) and afterload (15% decrease in SVR)
leading to hypotension (30% decrease in ABP)
n Dose- and rate-dependent decrease in cardiac
index, especially with preexisting cardiac
dysfunction
n Decreases Qp:Qs
Propofol
n Hemodynamic effects of propofol in 30 children
n 3 groups: No shunt, L R and R L
n Decreased Qp:Qs lead to statistically significant
arterial desaturation in patients with cyanotic heart
disease (Qp:Qs < 1)
n In 2 patients oxygen saturations decreased >10%
n Situations where decreased afterload is BAD
(severe aortic stenosis and hypertrophic
cardiomyopathy)
n Cyanotic patients where systemic and
pulmonary vascular resistances need to be
balanced (HLHS after Norwood or TOF)
n Any significant cardiomyopathy
Avoid Propofol In...
Ketamine:
The Good n Noncompetitive NMDA receptor antagonist
n “Dissociates” cortex from the limbic system
n “Cocaine-like” effect: Increases circulating NE and
reduces neuronal reuptake maintenance of
SVR
n Analgesic, bronchodilator, maintains HR
Cave DA et al. Anesthesia for noncardiac procedures for children with a Berlin Heart EXCOR Pediatric
Ventricular Assist Device: a case series. Pediatric Anesthesia 2010; 20: 647-659.
Consider mentioning good
SVR effects in kids with
Berlin Hearts - might be
drug of choice
Ketamine: The Bad
n Increased secretions/salivation, bad dreams,
emergence agitation
n Negative inotropic effects in human heart muscle
n Chronic illness, prolonged hyperdynamic state or
patients on drugs like dopamine (depletes
catecholamine stores) can lead to worsened
cardiac performance
Sprung J et al. Effects of ketamine on the contractility of failing and nonfailing human heart muscles in vitro.
Anesthesiology 1998; 88: 1202-1210.
Schecter WS et al. Anaesthetic induction in a child with end-stage cardiomyopathy. Can J Anaesth. 42; 1995: 404-
408.
Bovill JG. Intravenous Anesthesia for the Patient with Left Ventricular Dysfunction. Seminars in Cardiothoracic and
Vascular Anesthesia 2006; 10: 43-48.
Etomidate
n GABAA receptor agonist
n Excellent hemodynamic stability, even in the
failing heart
n No good studies in children with severe
ventricular dysfunction
Sarker M et al. Hemodynamic responses to etomidate on induction of anesthesia in pediatric patients.
Anesthesia & Analgesia 2005; 101: 645-50.
Sprung J et al. The effects of etomidate on the contractility of failing and nonfailing human heart muscle.
Anesthesia & Analgesia 2000; 91: 68-75.
n 12 children with SVT or ASD for cardiac
catheterization
n 0.3 mg/kg bolus etomidate
n No significant changes in hemodynamics
n Further studies needed in children with
cardiomyopathies
n Improved myocardial oxygen supply/demand
ratio
n Lack of histamine release
n Absence of malignant hyperthermia
n Lack of effect on hepatic and renal function
n Lack of dissociative hallucinogenic side effects
Etomidate Pros
Sarker M et al. Hemodynamic responses to etomidate on induction of anesthesia in pediatric patients.
Anesthesia & Analgesia 2005; 101: 645-50
Etomidate Cons n Dose-dependent adrenocortical
suppression
n Pain on injection (acidic pH)
n Myoclonus
n Tremors and seizures
n Anaphylactoid reaction
n Possible platelet inhibition Sarker M et al. Hemodynamic responses to etomidate on induction of anesthesia in pediatric patients.
Anesthesia & Analgesia 2005; 101: 645-50
Fentanyl-Midazolam
n Analgesia and amnesia
n Hemodynamically stable
n Decreased HR, despite preserved contractility
leads to decreased cardiac index
n Decreased sympathetic tone
n Combination use increases risk of circulatory
depression
Monday Morning, 7:30am...
\\
n Eight-year-old boy with dilated cardiomyopathy
(DCM), skeletal myopathy and hepatic fibrosis
secondary to juvenile polysaccharidosis
presents for percutaneous placement of a
gastrostomy tube for nutritional support
n What are the risks and how do you proceed?
Schecter WS et al. Anaesthetic induction in a child with end-stage cardiomyopathy. Can J Anaesth 1995;
42: 404-408.
On children with end-stage
cardiomyopathies...
“The only procedure for which
they should have an anesthetic
is cardiectomy for
transplantation.”
Preoperative Evaluation
n Echo: DCM, shortening fraction of 15%
n ECG: SR, First degree AV block, left bundle
branch block, lateral ST-T segment
abnormalities
n History of ventricular tachycardia
n On 10-day course dobutamine to optimize
ventricular function
Case Induction
n Dobutamine infusing at 7.5 mcg/kg/min
n Midazolam (0.1 mg/kg), Ketamine (1.5 mg/kg),
Vecuronium (0.15 mg/kg) and Fentanyl (5
mcg/kg)
n Hypotension, loss of pulse, CPR with return of
perfusion and eventual extubation in PICU later
that night
Putting It All Together
n Eight-year-old boy returns to
operating room for PEG
n What might have gone wrong last
time and what do you do now?
Learning from our mistakes...
n Primary myocardial depression from ketamine?
n Decreased HR from combination of opioid and
vecuronium leading to decreased cardiac
output
n Sympatholysis from opioid/benzodiazepine
combination leading to decreased LV filling
n Decreased beta receptor density and sensitivity
from chronic stimulation (dobutamine infusion)
Schecter WS et al. Anaesthetic induction in a child with end-stage cardiomyopathy. Can J Anaesth 1995; 42: 404-408.
Take Two n Dobutamine infusion increased prior to
induction
n Etomidate (0.3 mg/kg), midazolam (0.05
mg/kg), rocuronium (0.6 mg/kg)
n No change in blood pressure or heart rate
n Anesthesia maintained with isoflurane 0.25%
and fentanyl (total dose 8 mcg/kg)
n Extubated and transferred to PICU in stable
condition
Take Home Points
n Adequate preparation and risk stratification can
help minimize anesthetic risk and facilitate a
smoother perioperative course
n Taking care of children with cardiomyopathies
requires a coordinated approach with multiple
pediatric specialists