Pain Management in the Pediatric Emergency Department

Veronica Carullo, MDChief, Pediatric Pain Management Service

Cohen Children’s Medical CenterMarch 16, 2011

Disclosures

I have no financial relationships or affiliations to disclose.

I do not intend to discuss any off-label or investigational use of drugs or products in my presentation.

Objectives

Overview of pain in children Pediatric pain assessment Pharmacologic and nonpharmacologic

approaches to pain management in the ED• Injuries

• Procedural pain

Background Historically, children and infants received

less post-operative and procedural analgesia than adults

Well documented that children are often undertreated for pain• Kids were half as likely as adults to receive pain

medications in the ED for painful conditions (i.e. fractures, burns, sickle cell pain crises)

• 30% kids vs. 60% adults got pain meds

Selbst & Clark, Ann Emerg Med, 1990

What distinguishes pain in childhood from adult pain?

IASP: “An unpleasant sensory or emotional experience associated with actual or potential tissue damage, or described in terms of such damage.”• The inability to communicate pain verbally in no way negates the

possibility that an individual is experiencing pain and in need of treatment.

In pediatrics, pain is an “inherent quality of life that appears early in development and serves as a signaling system for tissue damage.”

Pain may be modulated by developmental stage, affective state, cognitive state, prior pain experiences, distress or suffering.

Cassell. NEJM 306:639,1994 Anand KJS and Craig KD Pain 67: 3, 1996

Barriers to Pediatric Pain Control

Belief that children, especially infants, do not feel pain the way adults do

Lack of routine pain assessment Lack of knowledge in pain treatment Fear of adverse effects of analgesics,

especially respiratory depression and addiction

Belief that preventing pain in children takes too much time and effort

Pediatrics, 18 (3) 2001

Jeffrey Lawson, 1985

Landmark seminar paper

Pain and its effects in the human neonate and fetus, 1987, NEJM. Anand & Hickey.• Called into question the widely held belief that

neonates do not have the neurophysiologic apparatus required to experience pain

Developmental Anatomy of Pain

Cutaneous nociception: sensory terminals are present in the perioral area at 7 wks GA, with spread to all body areas by 20 wks GA

Dorsal horn: A fibers enter the spinal cord prior to C fibers at 8-12 wks; A and C fiber territories overlap at birth in the developing substantia gelatinosa

Developmental Anatomy of Pain

Ascending pain pathways: completely myelinated in the spine and brainstem between 22 and 30 wks GA; myelination extends to thalamus at 30 wks; to cortex at 37 wks-term

Descending inhibition: develops post term• Pain sensitivity may be more profound Nervous system less

effective at blocking painful stimuli

Pain in children is still undertreated

By health care professionals• Fear of adverse effects - inadequate knowledge of drug

dosing and safety across the spectrum of ages

• Legal concerns about diversion or abuse

• Inadequate assessment and patient disbelief

• Costs and availability of medication By parents

• Lack of adequate instruction by health care professionals

• Fear of addiction and tolerance By patients themselves

• “Suffer in silence”

Pediatric Pain Assessment

Pain assessment = the crucial first step in Pain assessment = the crucial first step in managing painmanaging pain

Pain is multidimensionalPain is multidimensional

• Includes sensory, affective, cognitive, behavioral, sociocultural, and physiologic dimensions• Interactions of above components explain variations

that exist in patients’ response to pain and perception of pain

Frequent reassessment just as importantFrequent reassessment just as important

Health care providers need to use age-appropriate validated pain scoring tools• Child self-report = gold standard

• Must use an age-appropriate, reliable, and valid pain tool

• Infant or young child • May be assessed with behavioral pain tools coupled

with a parent report The lower age limit for successful use of a self-

report pain scale is generally 3-4 years old (Hicks et al., 2001; Wong & Baker, 1988)

Pain Scoring Tools

Physiologic measures

Provide information about general distress levels but are not sensitive or specific indicators of a child’s pain

Should only be used as adjuncts to self-report and behavior ± parental report

Pain in the ED

Injuries: contusions, strains, sprains, and fracture

Rest and splinting Oral analgesics

• Acetaminophen

• NSAIDs

• Aspirin

• Opioids (i.e. Hydrocodone / Oxycodone)

• Intravenous analgesics for moderate to severe pain as with displaced fractures

Most commonly used analgesic drug in pediatric practice Centrally-acting prostaglandin synthetase inhibitor Antipyretic and analgesic activity but minimal anti-

inflammatory effects Highly effective as sole analgesic for mild to moderate pain Synergistic when used in combination with NSAIDs and

opioids for moderate to severe pain Oral dosing: 15 mg/kg q 4 hours Rectal dosing: 30-40 mg/kg, followed by 20 mg/kg 6 hours

later Daily max: 90 mg/kg children, 80 mg/kg neonates, 60 mg/kg

premature infants

Acetaminophen

Non-steroidal anti-inflammatory drugs (NSAIDs)

Nonselective inhibitors of peripheral cyclooxygenase (COX) Provide excellent analgesia with good safety margin Children appear to have lower incidence of renal and GI side

effects than adults even with chronic administration Except in newborn period, when t1/2 after administration is

significantly longer, the pharmacodynamics and pharmacokinetics in children similar to that of adults

Dosing guidelines:• Ibuprofen PO 6-10 mg/kg q6h• Naproxen PO 5-6 mg/kg q12h• Ketorolac IV 0.5 mg/kg q6h

• Comparable with opiates for treatment of postoperative pain and orthopedic injuries with less sedation and fewer side effects

Opioids Most commonly used analgesic for moderate to

severe acute pain Marked individual variation in opioid dose

requirements; therefore doses must be titrated to effect

Come in different levels of potency and efficacy Combined with acetaminophen for synergistic

effect Oral dosing guidelines:

• Hydrocodone: 0.1-0.2 mg/kg/dose q4h• Oxycodone 0.05-0.1 mg/kg/dose q4h

Codeine

Codeine

Phenanthrene alkaloid derived from morphine• Change in the methyl group on 3 position (substituted for the hydroxyl group)

One tenth the potency (analgesic properties) of morphine Prodrug – has very little to no analgesic properties in and

of itself • Metabolized in liver by CYP2D6 to become an active morphine metabolite

Commonly administered orally in combination with acetaminophen At least 10% of American population does not have enzyme

necessary for conversion (genetic polymorphisms)• Not all enzyme systems are turned on at birth

• Newborns do not have CYP2D6; therefore, no analgesic properties with codeine, only vomiting

Very narrow therapeutic window, so genetic variability in metabolism is more likely to have a relevant clinical effect

Gold standard• Widely studied in infants and children

Metabolized by liver, excreted by kidney Histamine release can lead to decreased peripheral

vascular resistance and hypotension• Only of concern if child has severe injury and showing signs of

hypovolemia Full term infants < 3 months have decreased morphine

clearance (reduce starting dose by 25-50%)• 10-20 hrs in preterm infants and 1-2 hrs in young children • Continuous pulse oximetry recommended

Children < 11 yrs have higher clearance and larger volume of distribution for morphine and and its glucoronides

Dosing: 0.05-0.1 mg/kg IV/SQ q3h

Morphine

Synthetic opioid which is 50-100 times more potent than morphine

Highly lipid-soluble with rapid entry into the brain very rapid onset (2-5 minutes) and short duration of action (30-45 minutes)• Ideal choice for ED

Eliminated almost entirely by hepatic metabolism Rarely causes hypotension

• Excellent choice for injured children with severe pain Can rarely cause chest wall rigidity at high doses (>15

micrograms/kg)• Reversible with naloxone, but succinylcholine may be required

Dosing: 2-3 micrograms/kg IV q1h

Fentanyl

Procedural Pain

Patients seldom remember how great a clinician you are, but they DO remember how much or how little they hurt when you were treating them.

Procedural Pain Consider the type of procedure, expected

duration of pain, the patient and parents involved, and child’s pain history

Educate the parents and patients on what to expect

Utilize combination of non-pharmacologic and pharmacologic methods maximizing topical/local anesthetics

Calm environment Consider anxiolytic/sedation

Widely used for pain associated with needle pricks, IV placements, lumbar punctures, laceration repairs, and procedures on superficial skin lesions

Topical Analgesics

LET

Lidocaine Infiltration – Decreasing Pain

Buffer with bicarbonate (9:1 mixture)• Decreases pain of injection by neutralizing

acidic pH of lidocaine Warm to body temperature Inject slowly! Use smallest gauge needle (30-gauge) Inject directly into wound rather than

through intact dermis

Anxiolytic + Analgesic Combination

Benzodiazepine (Midazolam) + Opiate (Fentanyl or Morphine)• Amnesia, sedation and muscle relaxation

Safe and effective in children Likelihood of respiratory depression

increases with use of a sedative• Proper precautions to protect the airway must

be taken

Nitrous Oxide-Oxygen Analgesia Advantages

• Painless delivery

• Odorless, tasteless

• Rapid onset, short duration of action

• Produces sedation, amnesia and dissociation

• May be used in young children

• Safe when mixed with oxygen

Disadvantages• Fail-safe system

required

• Equipment expensive

• Scavenger device needed

• Requires patient cooperation

• Increased incidence of vomiting

• Greater personnel demands

N2O Self-Administration by a 3-year-old

Ketamine hydrochloride PCP derivative; NMDA receptor antagonist Analgesic, amnesic, and sedative properties

without loss of protective airway reflexes Causes dissociative amnesia Rapid onset (IV: 1 min, IM: 5-10 min) Dosing: 0.5-2 mg/kg IV or 4-5 mg/kg IM Adverse reactions: Laryngospasm, emergence

reactions (less common in children than adults)• Atropine (0.01 mg/kg) or Glycopyrrolate (0.005 mg/kg)

to prevent excess salivation• Benzodiazepine may decrease likelihood of

emergence reaction

Propofol Non-opioid, nonbarbiturate sedative-hypnotic given

intravenously for sedation during short procedures Potent sedative with amnesic properties; no analgesic

properties Rapid onset of action (3 sec - 1 min) and rapid recovery

phase (5-10 minutes) Use outside of OR by non-anesthesiologists controversial Low complication rate comparable to midazolam in one

pediatric ED study, but advantage of shorter recovery time with propofol (small sample size)1

Dosing: Initial bolus 1-2 mg/kg, followed by maintenance infusion of 60-100 microgram/kg/min

1Havel et al. Acad Emerg Med 1999

Propofol for ED PSA - Concerns

Difficult to titrate to desired sedation endpoints without overshooting to apnea and hypotension

Loss of protective airway reflexes during apneic periods likely places patients at increased risk of pulmonary aspiration, especially if positive pressure ventilation administered• Gastric insufflation likely induces passive regurgitation

Propofol for ED PSA – Concerns (continued)

Patients must be carefully screened for “full stomachs” and difficult airways.

Propofol should only be used by providers with in-depth knowledge of its adverse effects and skilled in airway assessments and positive pressure ventilation.

When propofol is administered, an experienced provider must be dedicated to administering the sedation, managing the airway and cardiorespiratory status of the patient, and not involved with the procedure being performed.

Propofol in ED– future research

Prospective, randomized studies of pediatric patients undergoing procedural sedation with propofol in the ED needed to better clarify:

• Risks of adverse events

• Effectiveness of distress reduction, amnesia

• Recovery and post-recovery experiences

Etomidate Rapidly-acting intravenous sedative-hypnotic; no analgesic

properties Fast onset (15-45 seconds), short duration of action (5-10

minutes) Advantage of maintaining cardiovascular stability Minimal effects on ventilation when used alone, although rapid

administration can lead to transient apnea Common side effects: nausea, vomiting, myoclonus Dosing: 0.1-0.2 mg/kg IV

Three reports of use in pediatric ED for procedural sedation:• Dickinson: Acad Emerg Med,2001• Ruth: Acad Emerg Med, 2001• Vinson: Ann Emerg Med, 2002

Etomidate – future research Prospective, randomized studies of

pediatric patients undergoing procedural sedation with etomidate in the ED needed to better clarify:• Standardized protocol

• Dose (titrated to effect?)• Analgesic adjunct• Procedure specific• Impact of myoclonus on CT scans, suturing?

• Elucidation of risk of apnea, aspiration

Dexmedetomidine

Selective alpha-2-agonist with analgesic and sedative properties and minimal effect on respiratory drive or cardiac function

Preliminary studies in pediatric patients demonstrate it is a safe and effective alternative for children undergoing diagnostic imaging• Associated with a much shorter recovery time and less

need for adjuvant sedatives

Nonpharmacologic Techniques

Effect of environment itself must be considered

Presence of child life therapists who are trained in nonpharmacologic techniques for reducing pain is vital

Three broad categories:• Cognitive

• Behavioral

• Physical

General Principles ofPediatric Pain Management

Anticipate & prevent pain Assessment is a continuous process Reverse the reversible: treat the underlying

cause Use multi-modal approach

• Nonpharmacologic

• Pharmacologic Involve parents Use non-noxious routes Address associated psychosocial distress

Pediatrics in Review 2003; 24 (10)

Questions??