ISSUES IN PEDIATRIC AND ADULT OUTPATIENT CARE
| “OFF-SITE” PEDIATRIC ANESTHESIA— Joseph D. Tobias, MD, Vice-Chairman, Department of Anesthesiology,
Chief, Pediatric Anesthesiology, Russell and Mary Shelden Missouri Chair in Anesthesiology, and Professor of Pediatrics
and Anesthesiology, University of Missouri-Columbia School of Medicine, Columbia, MO
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| Anesthesia outside operating room (OR): important issues include location of anesthesia machine (including O2 and
nitrous oxide supply), monitoring, supplies and medications, scavenging, calling for assistance (eg, cellular phone), and
recovery (eg, location of recovery area); use regular anesthesia cart full of necessary supplies and complete anesthesia
machine; know location of O2 and suction; speaker’s institution uses portable monitor (eg, Propaq monitor) for transporting
after anesthetizing patient; location of magnetic resonance imaging (MRI) in hospital should be familiar to other
health care workers; policies for monitoring and management during and after sedation (American Academy of Pediatrics
and American Society of Anesthesiologists [ASA] good resources) should include presedation evaluation, npo status,
and personnel and training; helps prevent missteps
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| Procedural sedation: regardless of type of sedation, location, and procedure, safest option to use ASA monitoring guidelines
in all patients; speaker recommends using end-tidal CO2 monitoring; bispectral index (BIS) monitoring useful to
help identify problems, especially when using propofol (helps in titrating before problems occur)
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| Patient evaluation: teach nonanesthesia providers to perform preanesthetic evaluation, including vital signs and basic
physical examination
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| Documentation: informed consent; instructions; information about procedure; presedation evaluation; history and physical
examination; monitoring and drug administration (eg, time-based vital signs); discharge condition (and Aldrete score)
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| Discharge criteria: bring patient either to postanesthesia care unit (PACU) or to day-of-surgery sedation area; specific
criteria for discharge
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| Adverse events: most incidents occur when sedation done outside control of anesthesia personnel; Food and Drug Administration
database review of 118 adverse outcomes; reviewers agreed on causation of 95 events; associations with negative
outcomes included drug overdosing, drug combinations, use of nitrous oxide (especially by nonanesthesia providers,
eg, dentists, ED physicians, untrained pediatricians), dental offices, and lack of monitoring or appropriate resuscitation;
12 adverse events occurred at home, 2 before procedure (commonly when chloral hydrate given at home; one case of oral
midazolam at home); speaker suggests policy that no one gets sedated at home; nonhospital vs hospital events (more cardiac
arrests; no monitoring; inadequate resuscitation as cause; more death or permanent sequelae); policies to prevent
problems—preoperative workup, npo guidelines, equipment, monitors, medications, and discharge criteria should be
same as in OR
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| Special aspects of MRI: problems—difficult and limited access to patient, noise (use earplugs or headphones to block
out noise), ferromagnetic substances, monitoring, and temperature control; nonmetal laryngoscope available but difficult
to use; speaker performs anesthetic induction outside of MRI suite; use nonmetallic O2 tanks and plastic precordial
stethoscope; speaker allows parents to be present for induction (counsel about emergence agitation); team approach important;
after loading on table, 6- to 8-ft separation between patient and anesthesia provider; single expandable circuit effective
(room to ventilate patient); speaker uses MRI-compatible anesthesia machine and ventilators, circle system with
expandable hoses, and monitoring system; ventilator—similar to OR (speaker primarily uses sevoflurane for maintenance
and nitrous oxide for induction); monitoring—for oxygenation, pulse oximetry; for ventilation, end-tidal CO2 and
precordial stethoscope; for temperature control, liquid crystal skin patches (relatively inaccurate; no esophageal monitor
because of metal temperature probe; aural measurement provides intermittent temperature at start and end of case); wrap
patient in blanket to keep warm; damages—credit cards; pagers; watches; hazards (patient)—tracheostomy tubes; wire-
reinforced endotracheal tubes; metal intravenous (IV) hubs; clothing snaps; safety pins; jewelry (eg, body piercing); shrapnel
or bullets; permanent eyeliner; implanted surgical devices (eg, pacemakers, vascular clips, mechanical heart valves, internal
plates, wires, screws); hazards (medical personnel)—anything metal; implants (eg, pacemaker); anesthetic
techniques—sedation; general anesthesia (placement of laryngeal mask airway [spontaneous ventilation, sevoflurane]);
speaker uses general anesthesia 99% of time
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| Medications and techniques
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 | Inhalational anesthetic agents: easy to titrate, inhalational route, rapid onset and offset, amnesia and analgesia, and 100%
efficacy; disadvantages include anesthesia provider required, scheduling issues, location for administration, and cost
issues
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| Nitrous oxide: easy to administer, noninvasive route, rapid onset and offset, amnesia and analgesia, and inexpensive; Nitronox
machine used for administration; disadvantages include—environmental pollution (health care worker exposure),
abuse potential, low potency, and many physiologic effects
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| Midazolam: many advantages; nonparenteral routes (oral route used routinely in OR; IV preparation mixed with sweet
solution to hide taste; fat solubility dependent on pH [alters absorption]; delay in onset; one-time administration); intranasal
administration option in child who refuses oral medications (uncomfortable); dosing guidelines (oral, 0.25-1.0
mg/kg; rectal, 0.7 mg/kg [diluted to ≈2 mg/mL; more acceptable alternative than intranasal route])
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| Remifentanil: opioids often combined with benzodiazepine for procedural sedation; much interest in use outside OR
(high incidence of airway effects [eg, respiratory depression] when used for procedural sedation); speaker may use as
low-dose infusion or in combination with propofol for bronchoscopy (effectively blocks cough reflex; low incidence of
hypoxemia)
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| Propofol: speaker always uses infusion pump; disadvantages include cardiovascular effects (eg, hypotension), respiratory
depression, risk for bacterial contamination, and pain with injection; preservatives include EDTA, sodium metabisulfite,
and benzyl alcohol (lower pH with metabisulfite; differences in airway protective effects and potency); 2%
propofol in development (may be less potent)
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| Ketamine: speaker administers before propofol to reduce pain on injection; in child having MRI by procedural sedation
service—oral midazolam (Versed), lidocaine with prilocaine (EMLA), start IV, induce anesthesia with ketamine 1
mg/kg, and maintain with propofol infusion; advantages—respiratory stability, endogenous catecholamine release,
amnesia and analgesia, options for route of delivery, and effective in patients with congenital heart disease; can be administered
nonparenterally; give in dose of 10 mg/kg orally for bone marrow aspirate or when used instead of oral midazolam;
issues—increased cerebral blood flow and intracranial pressure, direct myocardial depression, increased
heart rate (HR) and blood pressure (BP), variable effects on pulmonary vascular resistance, emergence phenomenon,
eyes open and nystagmus (warn parents); practical application includes standard monitoring, glycopyrrolate, midazolam,
ketamine 0.5 mg/kg (repeat every 1-2 min as needed)
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| Barbiturates: used in induction of anesthesia and brief procedures; disadvantages include respiratory depression, hypotension,
and alkaline pH (incompatible with other infusions; tissue irritation); speaker’s institution does not encourage
use by nonanesthesia providers
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| Chloral hydrate: most frequently used for CT scans; effective in child <4 yr of age and in child without neurobehavioral
diagnosis; IV started with topical anesthetic cream; use for brief nonpainful procedure; monitor as with general anesthetic;
dosing of 80 to 100 mg/kg; onset 20 to 30 min
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| Dexmedetomidine (Precedex): α2 -adrenergic agonist; hepatic metabolism; IV formulation; sedation and anxiolysis in locus
ceruleus, decreased HR and BP, and analgesia; used for procedural sedation; study showed less need for rescue sedation
than with midazolam; relatively easy and safe for nonanesthesia providers to use; not effective alone for painful
invasive procedure; blocks hallucinogenic effects of ketamine and blunts HR increase associated with ketamine; combining
with ketamine also allows for faster sedation
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| Dermal and topical anesthesia: includes EMLA, 4% liposomal lidocaine (ELA-Max), and lidocaine iontophoresis;
EMLA relatively inexpensive, onset in 60 min, no significant adverse effects (reports of prilocaine toxicity in patients
with congenital enzyme deficiency), and should not be used on mucous membranes, denuded or burned skin
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| THE ADULT OUTPATIENT AND CARDIAC RHYTHM DEVICES —Barbara S. Gold, MD, Associate Professor of Anesthesiology,
University of Minnesota Medical School, Minneapolis
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| Introduction: >500,000 cardiac defibrillators and cardiac pacemakers implanted annually in United States; with publication
of each new study, indications and number of devices increase
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| Preoperative evaluation: determine whether patient belongs, whether device works, whether surgery will interfere with
device, and when patient can return home
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| Basic questions: why is cardiac rhythm management device (CRMD) required (rhythm problems or lethal arrhythmia)?
does device pace, defibrillate, or both? is patient dependent on device?
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| Indications for pacemaker: include sinus node disease, heart block, recurrent vasovagal syncope, and cardiomyopathy
(biventricular pacemakers placed in patients with significant heart failure [ejection fraction <35%])
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| Indications for implanted cardiac defibrillator (ICD): increased risk for life-threatening arrhythmia (eg, spontaneous
ventricular tachycardia [VT] or ventricular fibrillation [VF], ischemia, myocardial infarction with cardiac arrest, long QT
syndrome, and hypertrophic or familial cardiomyopathy)
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| Additional questions: consider factors that alter device function (eg, cautery, magnet) and if reprogramming by appropriate
personnel anticipated
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| Responses to cautery: electromagnetic interference (EMI); pacemaker may revert to asynchronous pacing, and/or cautery
may temporarily inhibit pacemaker function; erratic or elevated pacing rates; circuit damage (resulting in cessation of
function); direct coupling of lead within myocardium; difficult to predict interference from cautery
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| Responses to magnet: generally, magnet converts pacemaker to asynchronous mode; with ICD, magnet turns off tachyarrhythmia
capabilities and ICD will not fire during VT or VF; if combined device, pacemaker function unaffected; not
always apparent when tachyarrhythmia capability turned off; unlike pacemaker, response for ICD somewhat variable;
ICD should be reprogrammed after passing under magnet
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| Intraoperative scenarios in patient with pacemaker or ICD: 1) reprogramming unnecessary (no cautery expected or
so distant from patient that risk extremely low), 2) magnet applied, or 3) preoperative reprogramming necessary
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| No reprogramming: if determination made preoperatively that risk of EMI minimal, CRMD has not been reprogrammed,
no cautery, pacemaker functioning well preoperatively (“this is key”), and no magnet used intraoperatively, then further
intervention not warranted; patient can be discharged as any other patient; if there may have been cautery significant
enough to interfere with CRMD, difficult to determine; unipolar cautery has greater likelihood of interfering with device
than bipolar cautery; call pacemaker representative or nurse to interrogate device for possible interference; risk depends
on distance of bipolar cautery to device; chance for EMI minimal if cautery >6 in from device or lead (especially if device
<10 yr old; more shielding)
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| Magnet used: for most pacemakers, if magnet function “on”, pacemaker will revert to original settings from asynchronous
mode when magnet removed; in patient with ICD, application of magnet will not affect pacing function, but there will be
no response to VT or VF; on some models, removal of magnet from ICD will activate chime that signals restoration of
defibrillator mode; with magnets on combined device, tachyarrhythmia function “off,” but pacemaker function unaffected;
however, cautery interference with pacemaker function could result in cessation of pacemaker function and asystole
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| Preoperative reprogramming: first choice to suspend cautery; if cautery necessary, reprogram device (call pacemaker
representative into OR to reprogram; use of defibrillator pads “may not be a bad idea”); devices may behave differently
depending on manufacturer; minimal information required includes manufacturer, type of device, setting, age of device,
battery status, any special functions, and date of last interrogation; manufacturer’s representative must be available
to interrogate and manipulate device; if device reprogrammed preoperatively, manufacturer’s representative must
turn device on postoperatively
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| Basics: in OR, important to disable artifact filter on electrocardiogram so pacemaker spikes appear; pulse oximetry confirms
systole and acts as visual and auditory cue for perfusion; always have defribillator equipment and pads
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| Guidelines: majority of consultants and ASA Heart Rhythm Society members agree that postoperative patient treatment
should include interrogating and restoring cardiac rhythm device function in PACU or intensive care unitpostoperative interrogation/restoration
of function are basic elements of postoperative management; American Heart Association (AHA)
states that patients with implanted ICDs or pacemakers should have devices evaluated before and after surgical procedures;
evaluation should include determination of patient’s underlying rhythm; interrogation of device determines programs, settings,
and battery status; manufacturers state that prior to procedure, determine degree of pacemaker dependency and evaluate
pacing system to determine capture and sensing thresholds; in pacemaker-dependent patient, device should be
programmed to SOO or DOO mode; application of pacer magnet, in lieu of programming, will provide asynchronous pacing
(if magnet response “on”); after procedure, thoroughly evaluate pacing system by determining capture and sensing thresholds
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Suggested Reading
American Society of Anesthesiologists Task Force on Preoperative Fasting. Practice guidelines for preoperative
fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration. Anesthesiology 90:896, 1999;
American Society of Anesthesiologists Task Force on Perioperative Management of Patients with Cardiac
Rhythm Management Devices: Practice advisory for the perioperative management of patients with cardiac rhythm
management devices: pacemakers and implantable cardioverter-defibrillators. Anesthesiology 103:186, 2005; American
Society of Anesthesiologists Task Force on Sedation and Analgesia by Non-Anesthesiologists: Practice guidelines
for sedation and analgesia by non-anesthesiologists. Anesthesiology 96:1004, 2002; Atlee JL et al: Cardiac rhythm management
devices (parts I and II). Anesthesiology 95:1265, 1492, 2001; Berkenbosch JW et al: Prospective evaluation of
dexmedetomidine for noninvasive procedural sedation in children. Pediatr Crit Care Med 6:435, 2005; Berkenbosch JW
et al: Use of a remifentanil-propofol mixture for pediatric flexible fiberoptic bronchoscopy sedation. Paediatr Anaesth
14:941, 2004; Chung T et al: The use of oral pentobarbital sodium (Nembutal) versus oral chloral hydrate in infants undergoing
CT and MR imaging—a pilot study. Pediatr Radiol 30:332, 2000; Committee on Drugs. American Academy
of Pediatrics: Guidelines for monitoring and management of pediatric patients during and after sedation for diagnostic and
therapeutic procedures: addendum. Pediatrics 110:836, 2002; Cote CJ et al: Adverse sedation events in pediatrics: a critical
incident analysis of contributing factors. Pediatrics 105:805, 2000; Cote CJ et al: Adverse sedation events in pediatrics:
analysis of medications used for sedation. Pediatrics 106:633, 2000; Fleisher LA et al: ACC/AHA 2006 guideline
update on perioperative cardiovascular evaluation for noncardiac surgery: focused update on perioperative beta-blocker
therapy. J Am Coll Cardiol 47:2343, 2006; Jalowiecki P et al: Sole use of dexmedetomidine has limited utility for conscious
sedation during outpatient colonoscopy. Anesthesiology 103:269, 2005; Kleiber C et al: Topical anesthetics for intravenous
insertion in children: a randomized equivalency study. Pediatrics 110:758, 2002; Koroglu A et al: Sedative,
haemodynamic and respiratory effects of dexmedetomidine in children undergoing magnetic resonance imaging examination:
preliminary results. Br J Anaesth 94:821, 2005; Motas D et al: Depth of consciousness and deep sedation attained in
children as administered by nonanaesthesiologists in a children's hospital. Paediatr Anaesth 14:256, 2004; Tobias JD:
Ketamine to reduce propofol injection pain. Paediatr Anaesth 14:611, 2004; Tobias JD: Sedation and analgesia in the pediatric
intensive care unit. Pediatr Ann 34:636, 2005; Zub D et al: Preliminary experience with oral dexmedetomidine for
procedural and anesthetic premedication. Paediatr Anaesth 15:932, 2005.
Cultural and Linguistic Resources
In compliance with California Assembly Bill 1195, Audio-Digest Foundation offers selected cultural and linguistic resources
on its website. Please visit this site: www.audiodigest.org/CLCresources.
Educational Objectives
| The goals of this program are to identify the pearls and pitfalls of “off-site” pediatric anesthesia and to improve perioperative
management of the adult surgical outpatient with a cardiac rhythm management device (CRMD). After hearing and assimilating
this program, the clinician will be better able to:
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| 1. Direct patient care and anesthesia administration outside the operating room (OR).
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| 2. Formulate policies and procedures for patient evaluation, monitoring, site evaluation, and record-keeping for anesthesia
outside the OR.
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| 3. Address special concerns associated with anesthesia for the patient undergoing magnetic resonance imaging.
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| 4. Explain the preoperative evaluation and preparation of the adult outpatient with a CRMD.
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| 5. Identify postoperative management responses in the patient with a CRMD as they relate to the preoperative and intraoperative
assessment and interventions.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members to disclose relevant
financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified
conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business
or commercial interest. For this program, the following has been disclosed: Dr. Tobias receives honoraria and research support
from Abbott, Baxter, Organon, and Hospira, and is a member of the Speaker’s Bureau for Johnson & Johnson.
Acknowledgements
Dr. Tobias spoke at Anesthesia Camp III, held October 5-7, 2006, in Laguna Beach, CA, and jointly sponsored by the Office
of Continuing Medical Education at State University of New York Upstate Medical University and destinationCME;
Dr. Gold, at the 60th Postgraduate Assembly in Anesthesiology, held December 8-12, 2006, in New York, NY, and sponsored
by the New York State Society of Anesthesiologists, Inc. The Audio-Digest Foundation thanks the speakers and the
sponsors for their cooperation in the production of this program.
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