Pain Management in Children

Definition of PainAs defined by the International Association for the Study of Pain (IASP), pain is "an unpleasant sensory and emotional experience associated with actual or potential damage, or described in terms of such damage."

Categories of Painassociated with a disease state (eg, arthritis, sickle-cell disease)associated with an observable physical injury or trauma (eg, burns, fractures)not associated with a well-defined or specific disease state or physical injury (eg, tension headaches, recurrent abdominal pain)associated with medical and dental procedures (eg, circumcisions, injections).

Physiology of PainNocioception is a physiologic mechanism of noxious stimulus transductionRequires a nocioceptorNot necessarily the same as “pain”Biologic role is protective

NocioceptorsNocioceptors are free nerve endingsUbiquitous distributionChemically activated in response to tissue damageInotropic/matabotropicNocioceptors can be sensitizedPrimary hyperalgesiaSecondary hyperalgesia

NocioceptorsFree nerve endingsHigh thresholdSlow pain

C fibers, unmyelinated, slow burning aching pain, Substance P

Fast pain

A delta fibers, myelinated, sharp prickly pain, glutaminergicA delta fibers project to projection neurons in laminas I and VC fibers project to projection neurons in lamina IIBoth also project to inhibitory and excitatory interneurons

Modulation of Pain Information

Gate Control TheoryNocioception arises from activation of nocioceptorsPain sensation is a product of several interacting neural systemsAfferent transmission relies on a balance in the activity of both the pain fibers and large proprioceptive/mechanosensory fibersInhibitory interneurons are spontaneously active and inhibit projection neurons

Dorsal Horn SynapsesNeurotransmitters

GlutamateSubstance PCGRPCCKOpiates

ReceptorsNMDANeurokinin-1??Endorphin (mu, kappa, sigma)

Supraspinal Pain Modulation

Pain transmission can also be modulated by descending pathwaysThe “analgesia” system

Analgesia SystemPeriaqueductal gray and periventricular areas (enkephalin)Raphae magnus nucleus (serotonin)Dorsal horn interneurons (enkephalin)A and C fiber Inhibition (pre- and post-synaptic)

Advances, but….Misconception that neonates, infants, and children do not feel or react to pain in the same way as adults.Fears of opioid addiction and adverse effectsRESULT: ineffective pain treatment for most pediatric patients

Postsurgical Stress Response

Metabolic, hormonal, and hemodynamic response to major injury or surgeryNeuroendocrine cascade with release of catecholamines, adrenocortical hormones, glucagon, and other catabolic hormonesResults in increased oxygen consumption, increased carbon dioxide production, hyperglycemia, and generalized catabolic state with negative nitrogen balance

Occurs even in preterm infants and the magnitude of the response correlates with mortalityAn inquiring, analytical mind; an unquenchable thirst for new knowledge; and a heartfelt compassion for the ailing - these are prominent traits among the committed clinicians who have preserved the passion for medicine.

PrinciplesUnrelieved pain has negative physical and psychological consequencesPrevention is better than treatment

Successful assessment and control of pain depends partly on a positive relationship between the health care professionals and the children and their families. Children often cannot or will not report pain to their health care providers Routine assessment increases the health care professional’s knowledge of the child which, in turn, optimizes the assessment of pain and its subsequent managementTechniques are now available that make pain reduction to acceptable levels a realistic goal in the majority of circumstances

Factors that Modify Pain Perceptions

AgeCognitionGenderPrevious pain experienceTemperamentCultural and family factorsSituational factors

Personalizing the Approach

Tailor assessment strategies to the child’s developmental level and personality style and to the situationObtain a pain history from the child and/or the parents.Learn what word that child uses for pain (hurt, boo-boo, owie) Elicit from the family culturally determined beliefs about pain and medical careMeasure the child’s pain using self-report and/or behavioral observation tools.

InfantsThere is not easy or scientific way to tell how much pain an infant is having

Not cryingMoaning or quietly cryingGently crying or whimperingStop crying when picked up and comfortedNot stop crying when picked up and comforted

ToddlersMay become very quiet and inactive while in pain or may become very activeMay use only one word (owie, booboo)Parents report that “they aren’t acting like they normally do”

Behavioral Observations

Use behavioral observation with preverbal and nonverbal children

VocalizationsVerbalizationsFacial expressionsMotor responsesBody postureActivityAppearance

FFACE

LEGS

ACTIVITY

L

A

CRY

No particular expression or smile 0

Occasional grimace or frown, withdrawn, disinterested

1

Frequent to constant quivering chin, clenched jaw

2Normal position or relaxed 0

Uneasy, restless, tense 1

Kicking or legs drawn up 2

Lying quietly, normal position, moves easily 0

Squirming, shifting back and forth, tense 1

Arched, rigid or jerking 2

No cry, (awake or asleep) 0

Moans or whimpers; occasional complaint 1

Crying steadily, screams or sobs. Difficult to console.

2C

Content, relaxed 0

Reassured by occasional touching, hugging or being talked to.

1

Difficult to console or comfort 2CONSOLE

C

Behavioral Observations

Interpret behaviors cautiouslyUse parent’s report of pain when the child is unwilling or unable to give a self-reportUse physiologic measures (eg. Heart rate and blood pressure) only as adjuncts to self-report and behavioral observation (neither sensitive nor specific as indicators of pain)

School-age and OlderCan often tell you more about pain using units of measure (0 is no pain and 5 is bad pain)Can color on body outlines where they hurt and show parents and health care providers where they hurt

Pain Assessment ToolsPoker chipWord-graphic rating scale

:

                                                                  

AdolescentsCan explain pain more clearly because they understand words and concepts that younger children don’tThey can use specific words to describe the character of the pain

Procedure-related PainProvide adequate preparation of the child and familyBe attentive to environmental comfort (If possible, do not perform the procedure in the patient’s room)Allow parents to be with the child

Procedure-related PainCombine pharmacologic and nonpharmacologic options when possible and appropriate

PharmacologicAnalgesics and/or local anestheticsSystemic analgesicsAnxiolytics or sedatives

Barbiturates and benzodiazepines produce anxiolysis and sedation but not analgesia

NSAIDsSignificant opioid dose-sparing effectsMust be used with care in patients with thrombocytopenia or coagulopathies

AcetaminophenAcetaminophen’s mechanism of action involves inhibition of central cyclo-oxygenase Additional mechanisms of action have also been suggested for acetaminophen, including inhibition of nitric oxide formation that results from activation of substance P and N-methyl-D-aspartate (NMDA) receptor stimulation. Available in various formulations, including drops, liquid, tablets, caplets, sustained-release tablets and suppositories. When dosing acetaminophen for pediatric use, consider its concentration in other medications that the patient may be taking, including weak opioids and over-the-counter flu, sinus or allergy medications

OpioidsCornerstone of management of moderate to severe acute painTolerance and physiologic dependence are unusual in short-term postoperative opiate-naïve patientsPsychologic dependence and addiction are extremely unlikely to develop after the use of opioids for acute pain

Opioids and Dependence

There is no known aspect of childhood development or physiology that indicates any increased risk of physiologic or psychologic dependence from the brief use of opioids for acute pain management

MorphineMorphine is the standard for opioid therapyIf morphine cannot be used because of an unusual reaction or allergy, another opioid such as hydromorphone can be substituted

MeperidineShould be reserved for very brief courses in patientsContraindicated in patients with impaired renal function or those receiving antidepressants of the monoamine oxidase inhibitor classNormeperidine is a toxic metabolite of meperidine and is excreted through the kidneyNormeperidine is a cerebral irritant – accumulation can cause effects ranging from dysphoria and irritable mood to seizures in otherwise healthy people

Dosing OpioidsTitrate the opioid dose and interval to increase the amount of analgesia and reduce the side effects when necessary

Children vary greatly in their analgesic dose requirements and responses to opioid analgesics, and the recommended starting doses may be inadequate

Use relative potency estimates to select the appropriate starting dose, to change the route of administration, or to change from one opioid to another

Provide opiates around the clock or by continuous infusion rather than as neededOffer rescue doses for breakthrough or poorly controlled pain

Use patient-controlled analgesia for developmentally normal children 7 years and older

Administration of Opioids

Administer opioids through intravenous catheter or orallyUse intramuscular injections only under exceptional circumstances

Alternative Routes of Administration

Regional anesthesia

Neonates and InfantsParticularly susceptible to apnea and respiratory depressionAppears to be dose-related

However, neonates and infants DO experience pain, and adequate analgesia is ESSENTIAL

Pain Assessments - Pharmacologic

What are the child’s and parents’ previous experience with pain?Is the child being adequately assessed?Are analgesics ordered for the prevention or treatment of pain?Is the analgesic dosage appropriate for the pain being experienced or expected?Is the timing of administration appropriate for the pain being experienced or expected?

Pain Assessments - Pharmacologic

Is the route of administration appropriate for the child?Is the child adequately monitored for the occurrence of side effects?Are the side effects appropriately managed?Has the analgesic regimen provided adequate comfort from the child’s or parent’s perspective?

NonpharmacologicSensorimotor strategies for infantsCognitive/behavioral strategies for older childrenChild participation strategiesPhysical strategies

DistractionBlowing bubblesPlaying with pop-up toysLooking through a kaleidoscopeImagining a superhero

Suggestion“Magic glove” techniqueBasic principles

Willingness to be involvedTrust in the coachAbility to participate

Breathing TechniquesRhythmic, deep-chest breathingPatterned, shallow breathing

Guided ImageryA form of relaxed, focused concentrationFavorite place, favorite activity

Not only produce distraction, but also enhance relaxation

Progressive Muscle Relaxation

Recognize and reduce body tension associated with painDecrease anxiety and discomfort

BiofeedbackUses instruments to detect and amplify specific physical states in the body and help bring them under one’s voluntary controlMechanism of pain relief is based on specific physiologic changes caused by the biofeedback

HypnosisAltered state of consciousness is usedConcentration is focused, narrowed, absorbed

Transcutaneous Electric Nerve Stimulation

Involves stimulation pulses produced by a battery operated unit delivered to skin electrodes surrounding the area where the pain is occurring

AcupunctureBased on a theory that energy (Chi) flows through the body along channels (meridians) which are connected by acupuncture pointsPain results when flow of energy is obstructedAcupuncture restores that flow and eliminates or reduces pain

Headache

Biofeedback and Relaxation in the Management of Pediatric HeadacheSummary and interpretation of controlled studies supports behavioral approach as a potent alternativeReview of research on behavioral treatments for recurrent headachesRelaxation and self-hypnosis is a well-established and efficacious treatment for recurrent headaches

Vaccine-related Pain

Attitude, empathy, instructionDistraction, hypnosisSugar nipplesTopical anesthetics (EMLA)56 references

Fracture Reduction

Hypnosis used to diminish pain and anxiety in patients with angulated forearm fractures (no other form of sedation or analgesia available)

Postoperative Pain

Emotional support, helping with activities, creating a comfortable environment used routinelyOther nonpharmacologic measures used less frequentlyRelated to background of the nurses

Recurrent Abdominal Pain

Fiber, Fiber-biofeedback, Fiber-biofeedback-cognitive/behavioral intervention, Fiber-biofeedback-cognitive/behavioral intervention-parental supportAll groups showed improvement, but treatment group showed more improvement

Rheumatic Illnesses

Massage helpful for JRA – marked decrease in subjective pain, observed pain, and tender trigger points

Pain Assessments -Nonpharmacologic

What are the child’s and parent’s experiences with and preference for the use of the strategy?Is the strategy appropriate for the child’s developmental level, condition, and type of pain?Is the timing of the strategy sufficient to optimize its effects?Is the strategy effective in preventing or alleviating the child’s pain?

Pain Assessments – Nonpharmacologic

Are the child and parent satisfied with the strategy for prevention or relief of pain?Are the treatable sources of emotional distress for the child being addressed?

AAP RecommendationsExpand knowledge about pediatric painProvide a calm environment for proceduresUse appropriate pain assessment tools and techniquesAnticipate predictable painful experiences, intervene, and monitor

AAP RecommendationsUse a multimodal approach to pain managementInvolve families, tailor interventions to individual childAdvocate for child-specific research in pain managementAdvocate for effective use of pain medication in children to ensure compassionate, competent management of their pain

Therapeutic AlliancePain is managed within a therapeutic alliance among the child, his or her parent, nurses, physicians, and other health care professionals