PEDIATRICS: PART 1
NEUROSURGERY AND TRAUMA PAIN
| NEUROSURGERY — Joseph N. Farlo, MD, Assistant Professor of Anesthesiology, Keck School of Medicine of the
University of Southern California, and Staff Anesthesiologist, Childrens Hospital Los Angeles
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| Basic goals: facilitate excellent operative conditions for surgeon; expedite surgical time as much as possible; accomplish
goals without inducing derangements in central nervous system physiology that might worsen neurologic outcome
(ie, preventing secondary neurologic injury)
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| Anesthesia for craniotomy: goals are to provide operative environment conducive to expedient surgery (cerebral
edema interferes with tumor exposure) and to prevent secondary neurologic injury (surgical factors include brain
retraction [reduces regional perfusion to cortex]; anesthetic factors include reducing cerebral perfusion)
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 | “Slack brain”: reduce cerebral swelling; ensure unimpaired venous drainage (by proper head positioning and avoiding
jugular cannulation); avoid hydrocephalus; reduce cerebral blood volume
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| Reduce cerebral swelling: ensure adequate pharmacologic anti-inflammatory therapy preoperatively; begin steroids
6 to 8 hr before surgery; ensure appropriate parenchymal dehydration with aggressive early use of diuretics (eg,
furosemide [Lasix]; mannitol); restrict overall volume of crystalloid infusion; avoid fluids containing significant
free water (especially lactated Ringer’s solution with low sodium content) and albumin that can potentially “third
space” into inflamed brain; in severe cases, give hypertonic saline, 6 mL/kg, administered ≤1 mL/min (follow serum
osmolarity closely)
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| Reduce cerebral blood volume: by reducing cerebral blood flow and reducing cerebral metabolic rate (induces hypothermia;
reduces bioelectric output of brain through burst suppression); no clear evidence that hypothermia
neuroprotective in humans; definitive proof also lacking for pharmacologic neuroprotection; hyperventilation
does not reduce cerebral blood volume significantly, but does cause reduction in arterial delivery (causes global
and regional reductions in O2 supply to brain); also causes respiratory alkalosis that shifts O2 -hemoglobin dissociation
curve (reduced offloading of cellular O2 ) and release of excitotoxic neurochemicals (eg, glutamate,
dopamine); research now indicates hyperventilation harmful in neurosurgical patient undergoing ischemia
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| Protocol: on induction, give barbiturate or etomidate, dexamethasone (Decadron), furosemide (Lasix), mannitol,
phenobarbital and passively begin cooling patient; during maintenance of therapy, restrict all intravenous (IV) fluids;
start propofol infusion; remifentanil used as narcotic; phenylephrine infusion to maintain mean blood pressure
(BP) of 65 to 85 mm Hg; reduction in cerebral perfusion pressure definitively causes secondary neurologic injury;
continue to passively cool to between 34.5° and 35.0°C at time of craniotomy; induce burst suppression at time of
brain retraction with propofol bolus followed by infusion; use bispectral index (BIS) monitoring to maintain suppression
ratio of 75%; continue low-dose volatile anesthetic but avoid causing cerebral vasodilation; on emergence
(after removal of retractors), turn off propofol and volatile anesthetics; convert to nitrous oxide and
remifentanil during 30 to 40 min required to finish closing skull and awaken patient; replace fluid deficit (urine
output plus 10 mL/kg) with warm fluid
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| Anesthesia for spinal surgery: primary goals include providing operative environment conducive to expedient surgery
(blood loss increases exponentially with time), preventing secondary neurologic injury, and ensuring optimum conditions
for early detection of injury, if one occurs
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| May be conflict between controlled hypotension and prevention of secondary neurologic injury (decision made on
individual basis); harbingers of secondary injury include ongoing injury with abnormal neurologic examination,
radiographic evidence of spinal cord compression preoperatively, decompressive surgery, and high-risk scoliosis
surgery (eg, >90° curve; congenital scoliosis; severe kyphoscoliosis; Scheuermann’s kyphosis; same-day anteroposterior
surgery)
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| Preventing secondary neurologic injury: prevent venous engorgement to maintain spinal cord perfusion pressure;
nicardipine known to recruit blood flow to supraspinal muscles; preoperative administration of steroids, eg, methylprednisolone
(Solu-Medrol) 30 mg/kg, followed by infusion, or dexamethasone (Decadron) 1 mg/kg; mild
temperature reduction (35.5° to 36.0°C; lower temperatures interfere with evoked potential monitoring); normal
to slightly elevated CO2 ; mannitol and Lasix for rheology and perfusion to reduce spinal cord edema; administer
anesthetic that does not interfere with spinal cord monitoring (all IV agents have negligible effects on cortical somatosensory
evoked potentials and motor evoked potentials; nitrous oxide causes reduction in cortical amplitude;
halogenated agents reduce amplitude and latency)
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| Protocol: “absolute” IV anesthesia; midazolam given as premedication, followed by propofol and remifentanil bolus;
intubate without giving muscle relaxant; maintenance with propofol and remifentanil (titrate to BIS of 55);
stop propofol 20 to 30 min before end of case, and start nitrous oxide; stop remifentanil 10 to 15 min before
awakening patient
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| Anesthesia for craniofacial surgery: goals are to provide operative environment conducive to expedient surgery and
to prevent secondary neurologic injury; study showed that patients who receive erythropoietin preoperatively are
candidates for other blood-conserving strategies (eg, hypervolemic hemodilution); erythropoietin also increased
red blood cell mass in 4 wk by average of 28%; controlled hypotension used in 9 of 10 patients who received
erythropoietin; partial pressure of arterial CO2 (PaCO 2 ) maintained >35 mm Hg in all patients undergoing controlled
hypotension; preoperative erythropoietin allowed for safe effective intraoperative blood conservation
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| Protocol: erythropoietin, 600 U/kg twice weekly; administer iron and vitamin C; check hematocrit weekly; schedule
surgery for 4 wk later
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| TRAUMA PAIN MANAGEMENT — Michael H. Joseph, MD, Assistant Clinical Professor of Pediatrics and Anesthesiology,
Keck School of Medicine at the University of Southern California, and Staff Anesthesiologist, Comfort and
Pain Management Program, Childrens Hospital Los Angeles
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| Forward strides: pain management studies of long-bone fractures show children still underdosed, but improvements
being made; opioids given infrequently; nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen given to
only 60% of patients; study showed rate of prescribing pain medications approximately equal in pediatric emergency
department (ED) and general ED
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| Reasons for pain treatment: part of job requirement; morally and ethically correct thing to do; required by Joint
Commission on Accreditation of Healthcare Organizations (JCAHO) to assess and treat pain appropriately and to
inform patient about options; physiologic obligation (prolonged pain induces neuroplasticity; also causes stress responses,
decreased immunity, hypoxia, and psychologic deficits)
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| Myths about pain management: early use of opioids masks evolving pathology; pain cannot be avoided, so better to
finish procedure quickly (often used during fracture reduction); children become addicted, so best to use as little
opioid as possible
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| Pain perception: factors affecting perception include attention, arousal, sex, age, past pain experience, cognitive
level, family learning, meaning of pain, perception of control, and coping style (eg, attenders vs distractors)
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| Pharmacologic intervention: issues include familiarity with medication (being unfamiliar with drug makes its use
inherently unsafe), inpatient vs outpatient, availability of anesthesiologist, type of sedation, and age of patient
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| Opioids: to avoid problems, give small doses and titrate frequently (10- to 15-min intervals); monitor response and
effect of drug; fentanyl has better hemodynamic stability, but causes chest wall rigidity; hydromorphone 15 times
more expensive than equipotent dose of morphine, but causes less histamine release than morphine; meperidine
(Demerol) not for extended use because of nervous system irritability and potential for seizures, but does provide
more euphoria than other drugs (good for one-time use in ED); oxycodone speaker’s choice for oral opioid (does
not contain acetaminophen); speaker does not give codeine to opioid-naive patient; nalbuphine exhibits ceiling effect;
safe for moderate pain without causing abdominal dysfunction; not as effective when given orally
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| NSAID therapy: analgesic doses of acetaminophen somewhat in question, and probably age-dependent if administered
rectally; recommended dose 15 mg/kg every 4 to 6 hr, with maximum 4 g daily; before giving ibuprofen or
ketorolac, make sure patient does not have significant risk for bleeding or significant kidney injury; ketorolac good
adjuvant
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| Regional anesthesia: nerve block superior to IV regional anesthesia; IV regional superior to hematoma blockade; hematoma
block may be used by orthopedists (simply by injecting lidocaine into fracture hematoma); continuous epidural
infusion successful in traumatic injury, especially with amputation (helps prevent phantom limb pain and
significantly decreases opioid usage)
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| Local anesthesia: topical preparations should be used as much as possible (eg, with sutures); speaker uses LET
(lidocaine, epinephrine, and tetracaine) first to desensitize wound, then infuses with lidocaine; lidocaine with
prilocaine (EMLA) and lidocaine 4% (LMX4 ; formerly ELA-Max) roughly equivalent; study of LMX4 shows significant
decrease in bandage-change pain with abscess or other wound
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| Adjuvant medications: expected issues if patient not seen in appropriate amount of time or already fragile include
wind-up, neuroplasticity, activation of N-methyl-D-aspartate (NMDA) receptors, and more centralized pain; decrease
neural transmission and try to improve nerve buffering and antinociceptive pathways by using gabapentin
and tricyclic antidepressants; speaker gives gabapentin before amputation (or immediately after in case of traumatic
amputation); tricyclic antidepressants especially useful in posttraumatic patient having difficulty sleeping
(also improve centralized pain); significant anxiety or depression, especially if interfering with care, should be
treated with quetiapine (Seroquel) or olanzapine (Zyprexa); speaker uses clonidine, especially for burgeoning neuropathic
pain; other medications include ketamine, propofol, and nitrous oxide; movement in EDs to use both propofol
and etomidate
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| Nonpharmacologic intervention: patient must be conscious; preparation decreases anticipatory anxiety; information
provided should include child’s role, caregiver’s expectation of child during procedure or medical treatment,
course of action, and “what it’s going to feel like” (eg, describing needle stick as similar to pinch; with children, “if
you aren’t truthful with them, you lose credibility rapidly”); sitting position (vs lying down) gives more control and
comfort to child and allows parent to have job; relaxation can be achieved by controlled deep breathing (helps child
decrease anxiety; includes blowing bubbles, blowing party blower, screaming louder, and progressive muscle relaxation);
concept of distraction states that “the more immersed the patient is in distraction, the more effective
it is” (he or she experiences less pain); hypnosis best distraction (impractical in trauma patient; virtual reality
also somewhat impractical; currently being studied for IV placement in more controlled settings); engaging child in
conversation also helpful; other distractions include movies, music, singing, and reading (having parent read book
and display pictures reduces anxiety in entire group); positive reinforcement important (anything that can turn situation
from punitive to positive; improves self-efficacy)
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Educational Objectives
| The goal of this program is to educate the listener about anesthesia for neurosurgery and trauma pain management in
the pediatric patient. After hearing and assimilating this program, the participant will be better able to:
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| 1. Review anesthesia for craniotomy.
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| 2. Describe anesthesia for spinal surgery.
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| 3. Summarize anesthesia for craniofacial surgery.
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| 4. Examine the myths associated with pain management.
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| 5. Outline pharmacologic and nonpharmacologic measures for pain management.
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Discussed on This Program
Acetaminophen (N -acetyl-P -aminophenol; APAP) [many trade names]
Acetaminophen with codeine [Tylenol with Codeine, others]
Albumin human (normal serum albumin), 5% [several trade names]
Ascorbic acid (vitamin C) [several trade names]
Chloral hydrate [Somnote, Aquachloral Supprettes]
Clonidine HCl [Catapres, Duraclon]
Dexamethasone [Decadron, others]
Epoetin alfa (erythropoietin; EPO) [Epogen, Procrit]
Etomidate [Amidate]
Fentanyl citrate [Sublimaze]
Furosemide [Lasix]
Gabapentin [Neurontin]
Hydrocodone bitartrate and acetaminophen [Vicodin, others]
Hydromorphone HCl [Dilaudid, others]
Ibuprofen (many trade names)
Ketamine HCl [Ketalar]
Ketorolac tromethamine [Acular, Acular LS, Acular PF, Toradol]
Lactated Ringer’s Injection
Lidocaine HCl [LMX (formerly ELA-Max, lidocaine 4%), others]
Lidocaine with prilocaine [EMLA, EMLA Anesthetic]
Lidocaine-epinephrine-tetracaine (LET)
Mannitol [Osmitrol, Resectisol]
Meperidine HCl [Demerol]
Methylprednisolone sodium succinate [A-Methapred, Solu-Medrol]
Morphine sulfate (several trade names)
Nalbuphine HCl [Nubain]
Nicardipine HCl (Cardene, Cardene I.V., Cardene SR)
Nitrous oxide (N2 O)
Olanzapine [Zyprexa, Zyprexa Intramuscular, Zyprexa Zydis]
Oxycodone and acetaminophen [Percocet, others]
Oxycodone HCl (several trade names)
Papaveretum 12/13/05
Phenobarbital [Bellatal, Luminal Sodium, Solfoton]
Phenylephrine HCl (many trade names)
Propofol [Diprivan]
Quetiapine fumarate [Seroquel]
Remifentanil HCl [Ultiva]
Sevoflurane [Ultane]
Sodium chloride, hypertonic (several trade names)
Thioridazine HCl [Mellaril]
Suggested Reading
Attard AR et al: Safety of early pain relief for acute abdominal pain. BMJ 305:554, 1992; Chen E et al: Behavioral
and cognitive interventions in the treatment of pain in children. Pediatr Clin North Am 47:513, 2000; Joseph MH et
al: Pediatric pain relief in trauma. Pediatr Rev 20:75, 1999 (Erratum in: Pediatr Rev 20:375, 1999); Laffey JG, Kavanagh
BP: Hypocapnia. N Engl J Med 347:43, 2002; Petrack EM et al: Pain management in the emergency department:
patterns of analgesic utilization. Pediatrics 99:711, 1997; Selbst SM et al: Analgesic use in the emergency
department. Ann Emerg Med 19:1010, 1990; Soriano SG et al: Pediatric neuroanesthesia. Anesthesiol Clin North
America 20:389, 2002; Zeltzer LK et al: A psychobiologic approach to pediatric pain: Part 1. History, physiology,
and assessment strategies. Curr Probl Pediatr 27:225, 1997; Zeltzer LK et al: A psychobiologic approach to pediatric
pain: Part II. Prevention and treatment. Curr Probl Pediatr 27:264, 1997.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue,
the faculty reported nothing to disclose.
Drs. Farlo and Joseph were recorded at the 43rd Clinical Conference in Pediatric Anesthesiology, presented January
28-30, 2005, by the Pediatric Anesthesiology Foundation, Childrens Hospital Los Angeles and held in Hollywood,
California. The Audio-Digest Foundation thanks the speakers and the sponsor for their cooperation in the production
of this program.
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