Transcript Document
Advanced Sedation
Fellows’ Conference
9-26-07
Thao M. Nguyen, MD
PEM fellow
Emory University
Children’s Healthcare of Atlanta
Objectives
Review historical perspective of pain & sedation
Review presedation factors
Review common agents of procedural sedation
Review more restricted or up-and-coming agents
Review common complications of sedation
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Historical perspective
Pain in children are underreported, undertreated, and
misunderstood
Children do not get the same treatment as adults who have
similar painful conditions
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Misconceptions
Children….
• cannot experience pain due to a immature CNS
• have no memory of pain
• cannot quantify or qualify their pain (thereby pain
underestimated)
Physicians…
• are concerned about masking symptoms
• fear adverse effects
cardio-pulmonary decompensation
addiction
• lack sedation training
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Development Milestones
5
< 6 mo
reflect parent’s anxiety, withdraw from pain,
grimace, cry
6-18 mo
increase anxiety, fear pain, withdraw
18-24 mo
anxious, express pain – “ouch”
3 years
localize pain and identify cause visually;
environment and distraction are very important
5-7 years
understand pain, localize pain,
more able to cooperate
The old way
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The new way
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Sedation Goals
Alleviate anxiety
Minimize pain
Minimize negative psychological impact
Maximize amnesia
Control behavior to expedite efficiency and improve
quality
Maintain safety and minimize risks
Ensure safe discharge
BETTER OUTCOME
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Definitions
Sedation occurs along a continuum…
Analgesia
• Relief of pain
Minimal Sedation (anxiolysis)
• Responds to verbal commands
• Cognitive function and coordination may be impaired
• Ventilatory and cardiovascular not affected
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Definitions
Moderate
• Responds to verbal commands alone or accompanied
by touch. Airway, ventilation and cardiovascular
maintained
Deep
• Cannot be easily aroused but responds to noxious
stimuli. May require assistance to maintain airway
and adequate ventilation, cardiovascular maintained
General Anesthesia
• Patient cannot be aroused. Often requires assistance
to maintain airway and positive pressure ventilation.
Cardiovascular status may be impaired
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Presedation Factors
Factors relating to procedure:
• Duration of the procedure
• Pain as a side effect of a procedure
• Position required for the procedure
• Anxiety/Stress/inability to cooperate as a side effect of the
procedure
• Availability of rescue resources
Factors relating to patient:
• Discussed in further slides
Factors relating to provider:
• Dedicated sedation monitor
• Skills related to depth of sedation
• Back-up systems and ability to rescue
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ASA Physical Status Classification
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Class
Physical status
I
Healthy patient
II
Mild systemic disease, no functional limitation
III
Severe systemic disease that limits activity
IV
Incapacitating systemic disease that is a constant treat to life
V
Moribund not expected to survive 24 hrs without an operation
add E to any of above for emergent procedure
ASA examples
• Class I
• Class II
Unremarkable PMHx
Mild asthma, controlled SZ,
controlled diabetes, anemia
• Class III Moderate to severe asthma, pneumonia,
moderate obesity, uncontrolled SZ or DM
• Class IV Severe BPD, advanced degrees of
pulmonary, cardiac, hepatic, renal, or
endocrine insufficiency
• Class V Septic shock, severe trauma
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ASA I and II are usually appropriate candidates
ASA III cases should be individually considered
ASA IV and V, consult anesthesia or ICU
Presedation evaluation
History
Allergies
Meds
Past History – prior sedation/anesthesia
Last meal
Events
Exam
Airway--Mallampati
Heart
Lungs
Other
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Mallampati
Class I: soft palate, OP, uvula, pillars
Class II: soft palate, OP, portion of uvula
Class III: soft palate, base of uvula
Class IV: hard palate only
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Fasting
ASA Guidelines
• 2 hours clears
• 4 hours breast milk
• 6 hours light meal
• 8 full stomach
ACEP
• “recent food intake is not a contraindication for
administering procedural sedation and analgesia, but
should be considered in choosing the timing and target
level of sedation”
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Informed Consent
Make sure you have discussed it with the parents, signed
and in the chart
We have a CHOA sedation video in English and Spanish
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Preparations
Expect and be prepared for the worse
You should have the skills to rescue from one level higher than
anticipate
SOAPS
Suction
Oxygen
Airway equipment
BVM, blades, ETT
Pharmacy
Appropriate meds,
reversal agents,
emergency drugs
Special monitors
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MSMAID
Monitor
CR monitor (EKG, HR, RR),
BP, continuous pulse ox,
capnography
Suction
Medicine / Machine
Airway equipment
IV access
Drugs for rescue (includes O2)
Be familiar…
Route
Mechanism of action
How metabolized
Adverse reactions
Time to onset/offset
• Avoid dose stacking
• Avoid multiple drugs
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Common Agents
Chloral Hydrate
Benzodiazepines
• Midazolam
• Diazepam
Barbiturates
• Pentobarbital
• Thiopental
• Methohexital
Opiates
• Morphine
• Fentanyl
Ketamine
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chloral hydrate
Unknown mechanism of
action
Contraindicated in hepatic
or renal disease
May have paradoxical
excitement
Side Effects:
• Hypotension
• Cardiopulmonary
depression
• GI upset
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Dose: 25-100 mg/kg PO/PR
• Max 1 gram in infants
2 grams in children
Onset: 30-60min
Duration 4-9 hours
30 hrs in neonate
midazolam (Versed®)
Shortest acting benzodiazepine
PO
The most commonly used sedation
• Dose: 0.5-1 mg/kg, max 20mg
agent in children and adults
• Onset: 15 min
Provides potent sedation,
• Duration: 30-90 min
anxiolysis, and amnesia
Intranasal or Sublingual
No analgesia
• Dose: 0.2-0.5 mg/kg, max 10 mg
May be given IV, PO, IN, IM, PR
• Onset: 10-15 minutes
Bitter aftertaste so mix in Syrpalta
• Duration: 60 minutes
Burns in nose
IV
Contraindicated with narrow angle
• Dose: 0.05-0.1mg/kg, max
glaucoma and shock
0.6mg/kg or 10mg
• Onset: 2-3 min
• Duration: 60-90 min
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pentobarbital
barbiturates
drug of choice for head trauma, status
epilepticus
Side effects:
• Hypotension
• Myocardial depression
• Respiratory depression
• Bronchospasm- stimulate
histamine release
Contraindications:
• liver failure
• CHF
• hypotension
NO analgesia!
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Dose:
• 2-6 mg/kg/dose PO/PR/IM
• 1-3 mg/kg/dose IV
• Max dose is 150mg
Onset: 15-60 min
Duration: 1-4 hours
morphine
Opioid
Slower onset, longer duration
Better for procedures that have a
longer duration ( ≥ 30 minutes)
Histamine release can cause
flushing and itching
Side effects
Respiratory Depression
Hypotension
Bradycardia
Nausea
Urticaria
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Dose: 0.1-0.2 mg/kg IV/IM/SQ,
max 10-15 mg bolus, no ceiling
Onset: 5-10 minutes
Peak effect: 15-30 minutes IV
30-60 minutes IM
½ life = 2-9 hours (neonates)
Duration: 2-4 hours
fentanyl
Synthetic opioid
Excellent choice for pain
management & sedation with short
duration
75-200 times more potent with
much shorter half-life than MSO4
Rapid onset, elimination, and lack
of histamine release; metabolize in
liver
chest wall rigidity syndrome
associated with doses > 15 mcg/kg
and rapid infusion; reverse with
naloxone and/or paralytics
Respiratory depression may last
longer than the period of analgesia
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Dose is 1-2 mcg/kg over 3-5
minutes
Titrate to effect every 3-5 minutes
Onset: 1-2 minutes
Peak effect: 10 minutes
Duration: 30-60 minutes
Reversal Agents
Naloxone
• Competitive opiate antagonist
• 0.1 mg/kg IV/IM/SC/ET (min 0.1 mg & max 2 mg) Q2-3 minutes
until response; may repeat Q2-3 min
• ½ life = 1-2 hr
• 30 minute duration; monitor for re-sedation
• Reverses resp depression, sedation, and analgesia
• Rebound sedation and apnea may occur
Flumazenil
• 0.01mg/kg IV (max 0.2 mg) then 0.005-0.01 mg/kg Q1 min to total
max dose 1 mg. May repeat doses in 20 min, max 3 mg in 1hr
• Do not use in kids on chronic benzo due to seizure risk
If a reversal agent is required the patient must be observed for an
additional 2 hours from the time the reversal agent is given
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ketamine
Provides both analgesia and
sedation
Releases endogenous
catecholamines
• Preserves respiratory drive
and airway protective
reflexes
• Bronchodilator effect (good
for asthmatics)
• Maintains hemodynamic
stability
Rapid infusion causes
respiratory depression and
apnea
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Dose: 1-3 mg/kg IV
3-5mg/kg IM
Onset: 1 minute IV
5 minute IM
Duration:
• 60 min for sedation
• 40 to 45 min for analgesia
ketamine
COMPLICATIONS
• Laryngospasm (1%)
• Hypersalivation
• Apnea
• Vomiting
• Agitation/Hallucinations/Emergence Reactions
Older aged population
• Hypertension
• Increased Intracranial and Intraocular Pressure
• Myoclonus
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Less common agents
Propofol
Ketofol
Brevital
Etomidate
Dexmedetomidine
Nitrous oxide
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propofol (Diprivan®)
Diprivan
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propofol
Ultra short acting sedative
No analgesic
Dose dependent level of sedation
with rapid recovery time (high
lipid solubility)
Common adverse effects:
cardiopulmonary depression,
upper airway obstruction,
hypoventilation and apnea leading
to hypoxemia
Attending needs to be present
during the entire infusion!
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Dose:
• 1-3 mg/kg IV
• Repeat 0.5mg/kg Q2-3 min
Onset: 40 secs
Duration: 1-3 mins
Contraindicated in patients
with egg or soybean allergy.
IV site pain: 1% lidocaine
propofol
Lidocaine 1% 1 cc in PIV (use with tourniquet) 1 minute prior to
propofol
INDUCTION
• Draw up 3-5 mg/kg
• Give 1-1.5 mg/kg initially over 30-60 secs, then increments of
0.5 mg/kg
• Babies < 6mos or pts with CNS pathology usually require higher
dose (at least 5 mg/kg)
• Bigger kids start @ 1 mg/kg then 0.5 mg/kg
INFUSION
• Infusion 5 mg/kg/hr, titrate by 1-2 mg/kg/hr increments, max 18
Concurrent opioid therapy can be associated with an increased risk
of respiratory depression and hypotension
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Why is propofol so restricted in the pediatric population,
especially in the PICU settings?
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propofol infusion syndrome
1992, report of 5 children with croup or bronchiolitis in
an ICU, sedated with propofol and subsequently died of
metabolic acidosis and myocardial failure
- Bray -
1998, 18 critically ill pediatric pts experienced
bradycardia, asystole, severe metabolic acidosis, lipemia,
hepatomegaly and rhabdomyolysis
- CMAJ 2001
2001 FDA noted of higher death rates in PICU pts given
propofol for sedation in a randomized controlled trial.
- Medwatch 2001
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propofol infusion syndrome
Cornfield & Tegtmeyer
“Continuous Propofol Infusion in 142 Critically Ill Children”
Retrospective review of a case series
18 mo period; PICU & BMT; age 2 mo – 18 yo
Propofol infusion < 50 mcg/kg/min = 3 mg/kg/h
• Additional bolus of 1 mg/kg Q1h
RESULTS
• Median infusion 16.5 hrs; longest < 20 hrs
• Adequate sedation (no extubation or CVL dislodgement)
• Not assoc with metabolic acidosis or hemodynamic compromise
• Conclusion: continuous infusion of propofol for extended periods
of time should not exceed 67 mcg/kg/min = 4 mg/kg/h
Pediatrics 2002;110(6):1177-1181
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propofol infusion syndrome
Described in critically ill children given long term
propofol infusion
Severe metabolic acidosis and rhabdomyolysis
associated with hepatomegaly, lipemia, myocardial
failure and hyperkalemia
Relative absence in adults
Not associated with brief procedural sedation
Limited use to the physicians on the sedation team
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ketofol
1:1 mixture of ketamine
10 mg/ml and propofol
10 mg/ml
In theory, the opposing
hemodynamic &
respiratory effects of each
drug might be
complementary and
minimize overall adverse
effects
Prospective study of 114
procedural sedation and
analgesia events for
orthopedic procedures;
effective & safe; fast
recoveries (median 15
minutes)
- Willman 2007
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+++
---
Ketamine
Analgesia
Amnesia
Little respiratory/
CV depression
Vomiting
Laryngospasm
Propofol
Reliable sedation
Amnestic
Anti-emetic
Respiratory &
CV depression
Bradycardia
No analgesia
Dose: 1-3 mg/kg IV slow
push, usually 1-1.5 mg/kg
Onset: < 1 min
Duration: 15-20 min
methohexital (Brevital®)
Rapid, ultra short-acting
barbiturate anesthetic
Indication similar to propofol
and with egg or soy allergies;
$$$
Contraindicated in porphyria,
temporal seizures
Rapid infusion can lead to
transient hypotension &
tachycardia; respiratory
depression/apnea
Associated with hiccups,
coughing, muscle twitching &
rigidity, salivation, emergence
delirium
Metabolism in the liver
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Dose:
• IV 1-2 mg/kg induction of 1%;
3 mg/kg/hr infusion, titrate by 1.5
• IM 6.6-10 mg/kg of 5% sol’n
• PR 25 mg/kg, 10%, max 500 mg
Contraindicated in pts < 1 mo
Onset: 30 secs IV
2-10 mins IM
5-15 mins PR
Duration: 5-10 mins IV
etomidate
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Ultra short acting sedative-hypnotic
Unknown mechanism of action
Rapid IV induction
Minimal respiratory depression or
hemodynamic instability
No histamine release
Myocardial & cerebral protection
No analgesia
Adverse Reactions
• Nausea and vomiting – 5%
• Local burning infusion pain
• Myoclonic movements
• Inhibits steroid synthesis
Contraindications:
• Seizure disorder
• Children < 2 y/o
Dose: 0.2-0.5 mg/kg IV
Induction 0.3 mg/kg IV over 30-60 sec
Duration: 5-10 min
Full recovery in 30 min
Re-dose with 0.1mg/kg every 5-10
minutes as needed
Lidocaine 1% for iv site pain
etomidate
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Synthesized in 1964
1972 clinical practice in Europe
1983 approved for use in the US; promoted as a safe agent for
continuous sedation in mechanically ventilated pts.
• Trend toward increased mortality reported in critically ill, multitrauma pts receiving continuous infusion etomidate in the ICU;
25% vs 44%
- Ledingham and Watt
• Retrospective review of 428 multi-trauma pts from 1969-1982
increased mortality 28% vs 47%; p< 0.05
More pronounced with ↑ MV duration and means of sedation
(benzos 28% vs 77% etomidate; p< 0.0005)
All showed at least one subnormal level of serum cortisol
Long-term use of etomidate fell into disfavor
Package insert for etomidate: “this formulation is not intended for
administration by prolonged infusion.”
etomidate
Adrenal suppression
Single induction dose
• ↓ cortisol &
aldosterone levels
(30 mins)
• transient < 24 hrs
Inhibits conversion of
cholesterol to cortisol
by a reversible &
concentrationdependent blockade
of 11ß-hydroxylase
>> 17α-hydroxylase
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etomidate controversy
Ideal first-line induction agent for select ED pts requiring
RSI intubation; stability and predictability
Etomidate single use in septic shock
• Adrenal insufficiency is transient and clinically not
relevant VS
• Etomidate should be abandoned altogether in the ICU
increased the risk of adrenal insufficiency by 12X;
transient effect prolonged in critically ill pts;
poor prognosis associated with adrenal
insufficiency in critical illness
- Annane 2005
Meta-analyses support the use of low-dose steroid
replacement among pressor dependent septic shock pts
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etomidate controversy
3 approaches to the use of etomidate in septic shock pts:
• eliminate etomidate use altogether in this subgroup
Ketamine?
• use a lower dose of etomidate in conjunction with
lower doses of other induction agents
• routinely administer concomitant corticosteroids with
etomidate
Annane study showed 94% (68/72) were
nonresponders to high-dose cosyntropin
stimulation test
Mortality cost of adrenal suppression by etomidate
offset by corticosteroid administration
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dexmedetomidine (Precedex®)
Relatively selective α2adrenoceptor agonist with
sedative properties
preserves cardiorespiratory
function
maintained RR & oxygenation
less concurrent opiate use
not approved in children
adverse effects
• hypotension
• bradycardia
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Dose:
infusion 1 mcg/kg over 10 min
infusion 0.4 mcg/kg/h (0.2-0.7)
Onset: 6 mins
t½ : 2 hrs
nitrous oxide
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sweet smelling inorganic gas by Priestly in 1772
late 1800s dental procedures
analgesic & sedative properties
• 20% N2O = morphine
rapid onset and recovery
• 30-80% N2O LOC
suitable for use when short acting analgesia/sedation required for brief
procedures
adverse reactions:
• CNS depression
• Cardiorespiratory depression
• Exacerbate existing airway obstruction
• Worsened existing pneumothorax
• Megaloblastic anemia affects vitamin B12 metabolism
nitrous oxide
2 large prospective studies
• 0.35% (27 of 7679 children) major adverse events
O2 desats, airway obstruction, apnea, bradycardia,
oversedation
• All resolved within minutes of discontinuation
• Higher adverse event in pts < 1 yo (2.3%) and
received additional psychotropic drugs
• 5% minor adverse events: euphoria, nausea, vomiting,
dizziness, parasthesia
- Pena 1999
- Gall 2001
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nitrous oxide
Entonox
• fixed concentration of 50% N2O / 50% O2
• self-administered via a demand valve system with a
weighted mask
• oversedation less likely; young children cannot use
The Matrix Quantiflex nitrous oxide delivery system
• Variable delivery of N2O (0-70%) with oxygen
administered via a constant gas flow system that does
not require patient effort to trigger
• oversedation & respiratory depression more likely
• Need constant monitor
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Common Problems
Inadequate sedation
• Assessment/reassessment
• Evaluation of efficacy and duration
• Timely intervention
Excessive sedation/narcosis
• Special circumstances (shock, airway, CNS and concurrent
medications)
Most common causes of death
• Hypoxemia
• Airway obstruction
• Cardiovascular collapse (myocardial depression, vasodilation,
bradycardia, hypotension, arrhythmias)
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Hypoxemia
Is the airway patent?
• Upper airway obstruction common, especially in
patients predisposed to obstructive sleep apnea (preexisting obstruction, macroglossia, micrognathia, etc)
• Don’t merely give additional oxygen, but evaluate for
obstruction, and intervene as needed…
49
Sniffing position
50
Hypoxemia (cont’d)
If airway is clear, is patient breathing?
• Yes, but shallow/infrequent
Stimulate to breathe
Support with BVM, intubate if prolonged support
needed (or unstable airway)
Consider reversal agent (if available for choice of
sedative)
• No
As above, but don’t waste time attempting
stimulation or reversal – provide PPV
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BVM
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Hypotension
Treatment based on tachy/bradycardia, perfusion, sedative
Usually due to excessive sedation with myocardial insufficiency
(esp. with opiates) and/or vasodilation (esp. barbiturates, opiates,
benzos)
• Verify/obtain patent airway, assist ventilation, intubate if needed,
give 100% O2
• Fluid bolus 10-20 cc/kg rapidly
• Chest compressions if bradycardia or PEA
• Discontinue sedation (esp. if using continuous infusion)
• Consider reversal agent, atropine, epinephrine
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Post-sedation
If reversal agent administered, patient must be observed
for at least 2 hours after last reversal dose
Discharge criteria
• Airway patent and stable vital signs
• Easy arousability
• Ability to talk
• Ability to sit up unaided
• Well hydrated
• Taking po
• Patient/home care provider able to understand written
instructions
• Patient has safe transportation home (patient may
NOT drive self home)
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Conclusions
Sedation occurs along a continuum
Most serious adverse effects can be avoided by
appropriate patient and drug selection and assessment
• When in doubt, obtain anesthesiology consult
Anticipate potential problems, and be prepared to
intervene
PPV by BVM more important than sedation reversal
Titrate, titrate, titrate…
Evaluate, evaluate, evaluate…
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Citations
Annane D. ICU physicians should abandon the use of etomidate! Intensive Care Med
2005;31:325-6
Bray RJ. Propofol infusion syndrome in children. Paediatr Anaesth. 1998;8:491-9
Chang P, Warren D et al. Use of propofol sedation in the pediatric emergency department.
Paediatrics & Child Health. 2003;8
FDA issues warning on propofol. CMAJ 2001;164(11):1608
Gall O. Adverse events of premixed nitrous oxide & oxygen for procedural sedation in children.
Lancet. 2001;358:1-2
Hom J. Pediatics, Sedation. emedicine.com. Last updated January 29, 2007 Kraus & Green.
Sedation and analgesia for procedures in children. NEJM. 2000.342:939
Jackson WL. Should we use etomidate as an induction agent for endotracheal intubation in
patients with septic shock? A critical appraisal. Chest. 2005;127:1031-8
Morris C. Etomidate for emergency anaesthesia mad, bad and dangerous to know? [editorial].
Anaesthesia. 2005;60:737-40
Murray H. Etomidate for endotracheal intubation in sepsis. Acknowledging the good while
accepting the bad. Chest. 2005;127:1031-8
Pena BM. Adverse events of procedural sedation & analgesia in a PED. Ann Emerg Med.
1999;34:483-91
Willman EV. A Prospective Evaluation of “Ketofol” (Ketamine/Propofol combination) for
Procedural Sedation and Analgesia in the Emergency Department. Annals EM. 2007; 49(1):23-30.
Wooltorton E. Propofol: contraindicated for sedation of pediatric intensive care patients. CMAJ.
2002;167(5)
Zed PJ. Etomidate for rapid sequence intubation in the emergency department: is adrenal
suppression a concern? CJEM. 2006;8(5):347-50
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