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Cardiac Arrest in the Pediatric OR
1. Cardiac arrest in the OR
Cardiac Arrest in the
Immediate response:
Pediatric OR • Call for help!!!! 911?
• Stop anaesthetic/ventilate with 100% oxygen
Jerrold Lerman BASc, MD, FRCPC, FANZCA • CPR
Clinical Professor of Anesthesiology
Women and Children’s Hospital of Buffalo
• Differential diagnosis:
SUNY at Buffalo, • Identify most probable diagnosis, specific
And University of Rochester, intervention
Rochester, NY
• Use “lateral thinking”: consider alternate
diagnoses…
Perioperative Mortality
20 in children Cardiac Arrest
Mortality per 10,000 Anesthetics
Demographics:
Anesthesia-Related
15 Beecher
• India: 2003-08, non-CVS, ophthalmol
Clifton
• CA rate: 27/12,158 (1/3 due to anesthesia)
10 • Risk factors: < 1 yr, ASA ≥3 & Emergency
Rackow • Main causes: 56% resp, 33% CV
5
Graff • Mortality:
Smith Cohen • ASA 1/2, 1.2/10,000
Keenan
Smith • ASA ≥3, 7.7/10,000
Tiret Morray
Petruscak Romano Patel
0
1950 1960 1970 1980 1990 2000
Year Morray JP
Bharti N, et al
Eur J Anaesth 2009: Mar 18 epub
Anesthesiology Clinics N Am 2002;20:1-28
Cardiac Arrest POCA Registry Arrests
Demographics:
• 1988-2005: 92,881 anesthetics <18 yr
• 2.9 CA/10,000 non-cardiac Sx vs. 127/10,000 cardiac
Sx
• 0.65/10,000 CA due to anesthesia
• CA incidence and death was greatest in neonates
during CV Sx
• 88% of CA had CHD
Flick RJ, et al Bhananker SM et al.
Anesthesiology 2007:106;207
Anesth Analg 2007:344
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2. POCA Registry Data POCA Registry Data
Factors in 1998-03: Spinal fusion 8/1048% underestimated
• cases of electrolyte
Mortality factors: • 36% due to CVS causes Cranie
Imbalance, due to K+
blood loss
overdose from old blood
• 22% inadequate
• 193 CA reported between 1998 & 2004 • Hypovolemia IV access
• Multivariate analysis: • ⇑K+ 2 o to massive Tx of old blood • 22% no CVP or not
transduced
• ASA P/S ≥ 3: OR 4.4 compared with ASA <3 • 27% due to Resp causes
• Emergency surgery: OR 3.3 compared with non-emergency • laryngospasm, airway obstruction, inadequate O2, early
• (from 1994-2004, almost 50% of CA were <1 yr) extubation 9 Halothane, 6 Sevo
3 Succ
• Anesthetic period: • 20% due to Medication 2 Neostigmine
• Pre-induction and induction 24% • ↓ by 50%
• Maintenance 58% • Halothane, Sevoflurane, Succ
• Emergence, transport & recovery 19% • 4% due to Equipment
• CVP line insertion and sequelae
Bhananker SM, et al. Bhananker SM, et al.
Anesth Analg 2007:105, 344 Anesth Analg 2007:105, 344
Cardiac arrest
Hypovolemia/hypotension:
Tachycardia is good,
• Preoperative fasting interval is brief…or not
Bradycardia is bad!
• Establish adequate IV access…for site of Sx!
• Fluid = CO x SVR
⇓ BP Rx:
• 20-30 ml/kgfn {ANS, humoral}
SVR is a loading
Give volume ive volume,
⇑dP/dt
• Replace losses 3x blood volume
CO = HR x SV
• PRBC 4isml/kg/Gm Hb
SV a fn {preload, afterload, dP/dt}
Cardiac arrest Cardiac arrest
Fluid resuscitation:
• Intraoperative blood loss must be carefully Hyperkalemia:
assessed:
• Neonate -- systolic pressure α volume status • Caused by rapid direct infusion of old
• Older child – systolic pressure, CVP, UO, capnogram
blood in infants
• Use isotonic clear fluids to resuscitate…
• AVOID hyponatremic solutions! • Treatment requires immediate treatment
• 10-20 ml/kg rapidly with iv Calcium chloride 10 mg/kg (or
• Caution above 100 ml/kg
Calcium gluconate 30 mg/kg) repeatedly
• When blood loss is excessive (what is that?):
• colloid, blood products (PRBC 4 ml/kg gm Hb) until the arrhythmias resolved
• IV site (not through CVP)
• Temperature
• Calcium
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3. Smith, H. M. et al.
Anesth Analg 2008:106, 1062
Airway Obstruction Laryngospasm
Issues to panic over:
• I’m losing the airway!
• NO iv access yet!
• Isn’t there anyone younger in the department to do
these cases?
• Differential diagnosis:
• Oropharyngeal obstruction
• Glottic (laryngeal) obstruction
• Tracheo/bronchial obstruction
• Central apnea
Cardiac Arrest in the OR Laryngospasm
Laryngospasm: Predisposed with:
• Closure of the glottic inlet—vocal cord • ⇑ incidence In infants & young children
irritation due to foreign substance, light • ⇑ incidence in children with recent URI
anaesthesia • ⇑ incidence 5x with passive smoking
• Jones DT et al. Otolaryngol Head Neck Surg 2006:135;12
• ⇑ effort to inspire… ⇑ negative intrathoracic • ⇑ incidence GERD, secretions, blood
pressure…false vocal cords involute…closed • ⇑ incidence with UA disease (T&A)
glottis…hypoxia (N2O) • ⇑ with light anesthesia
• Schwartz D, et al. Ped Anesth 2004:14;820
• Hypoxia ⇒ bradycardia ⇒ cardiac arrest
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4. Laryngospasm
Why are children at ↑ risk?
• Difficult to apply tight-fitting mask
• ↑ minute oxygen requirement
• ↓ FRC…oxygen reserve
• preterm < neonate < infant < child < adult
• Especially if had been crying…atelectasis
• N2O rapidly comes out of blood
• Rapidly dilutes oxygen in alveolus
Pediatr Anesth 2008:18;303
Cardiac Arrest Cardiac arrest
Bradycardia: Medications:
• Definition: < 100/min infants, < 80/min children, • Anesthetics: Halothane ⇒ Sevoflurane
< 60/min adolescents
• Local anaesthetic toxicity
• Slow HR = Low cardiac output in infants
• Succinylcholine…hyperkalemia
• Most important is to AVOID this situation
• Rx: oxygen and atropine 20 µg/kg IV/IM • Miscellaneous drugs:
• If asystole occurs, do NOT waste time giving • Clonidine, 5-HT3
atropine…this is not a vagal response. Give • Drug swap/overdose:
EPINEPHRINE 10 µg/kg iv immediately with CPR • Esmolol, lidocaine
Inhaled Agents
In comparison to Sevoflurane:
• Halothane causes more hypotension
• Halothane causes more arrhythmias
• In children with CHD, two studies:
• Halothane caused ⇓ CI, HR, more hypotension
and negative inotropic effects
• Halothane assoc'd with more hypotension and
more pressors during emergence
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5. Cardiac arrest in the OR
Halothane Sevoflurane Inhaled agents:
Max = 5% Max = 8%
FA /FI = 0.35 FA /FI = 0.5
• Overfilled vaporizer
FA /FI (child) = 0.5 FA /FI (child) = 0.5 • Max deliverable
MAC equiv = MAC equiv = concentration…25-35%!
2.5%/1.1 or 4%/2.5 or
2.3 MAC 1.6 MAC
• In the first few minutes,
8-25% ET concentration
• Spontaneous ventilation
prevents an overdose!
Yasuda N, et al Yasuda, et al
Anesth Analg 1991:72;484 ovc.uoguelph.ca
Anesth Analg 1991
Halothane in Dogs Avoiding the Oops Factor
Strategies:
• Switch from Halothane to Sevoflurane:
• 95% of recent SPA members have switched
• Sevo maintains HR, BP…
• EF better than halothane
• Fewer arrhythmias
• better for CHD
• Establish adequate IV access
• Maintain normovolemia
• Avoid rapid Tx old blood…check K conc.
Gibbons RT, et al
Anesth Analg 1977:56;32
Intravascular injections Cardiac arrest in the OR
ECG changes after bupivacaine with
epinephrine:
• ST and T-wave changes
• Tachycardia is unreliable!
so watch the ecg continuously!
Fisher et al, CJA 44:592, 1997
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6. Cardiac Resuscitation Bupivacaine Toxicity
For bupivacaine toxicity: Lipid Regimen:
• Bretylium -- withdrawn • Based on animal data primarily
• 20% Intralipid 1 ml/kg every 3 minutes up
• Epinephrine?
to 3 ml/kg
• …CPR, time, prayers
• Intralipid infusion 0.25 ml/kg/min
• Maximum expected total volume expected
• SURENDIPITY! is 8 ml/kg
Bupi Resuscitation in Rats Malignant Hyperthermia?
Case:
• 3 year old male, RIH
• Healthy, motor dev?
• IV or inhaled induction, then
Succinylcholine
12.5 mg/kg
18 mg/kg
LD50 • Within 60 seconds, peaked T waves, V
Tach ⇒ to V Fib
Weinberg GL, et al.
Anesthesiology 1998:88;1071
Hyperkalemia Hyperkalemia
Intervention:
Scenario: • CPR resuscitation algorithm is NOT
• Sudden onset of v. fib/cardiac arrest in a appropriate for these arrests!
healthy child during induction of • ⇑ K+ may be extremely resistant to treatment:
anaesthesia
• Ca2+ restores the gradient between the resting and
• Assoc’d with the use of succinylcholine, threshold membrane potentials, no effect on K+
worsened with halothane level!
• This is NOT Malignant Hyperthermia! • Calcium chloride 10 mg/kg or Calcium Gluconate
30 mg/kg
• Occurs in patients with myopathies (males,
• Massive doses of Ca2+ may be required to restore
DMD), UMNL, LMNL, prolonged sepsis, NSR
burns (>7% SA)
• There is NO place for Dantrolene in these
patients.
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7. Cardiac arrest in the OR Cardiac arrest in the OR
Succinylcholine:
• Fastest onset/offset relaxant Outcome of arrests:
• Sevoflurane inductions… • Institute definitive treatment…restore
• Hyperkalemia after sux usually in young males circulation and prognosis excellent
• Sudden onset V. Fib/Tach
• As the number of failing organ systems
• Definitive Rx: iv Calcium chloride 10mg/kg
increase, the prognosis diminishes
(Ca gluconate 30 mg/kg)
• CPR to promote circulation of blood AND Ca2+ • As the duration of arrest increases,
• Immediately reversible…ecg reverts
prognosis diminishes
• Repeat doses of Calcium may be required
A Happy Outcome
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